CL0205 Handy Guide update v2 - Nevill Long · 52 Single timber frame wall lining and dormer cheeks 54 Timber frame wall sheathing ... Scotland Domestic Technical Handbook – Section

The CelotexHandy Guide

25%

Your essential guide

to understanding the new Building

Regulations

Innovation in insulation

Are you on target for Part L?

25%25%

T: 0901 996 0100 | celotex.co.uk | 3

04 ▶ The road to zero carbon06 ▶ Celotex – we know insulation inside and out08 ▶ Product descriptions16 ▶ Insulation solutions for pitched roofs18 Pitched roof sarking

20 Insulation between and over rafters

22 Insulation between rafters

24 Insulation between and under rafters

26 ▶ Insulation solutions for flat roofs28 Built-up flat roofing applications

30 Single-ply membrane systems using Celotex EL3000

32 Single-ply membrane systems using Celotex TA4000

34 Flat roof insulating deck

36 Insulation between and under joists

38 ▶ Insulation solutions for walls40 Masonry cavity walls

42 Blockwork comparison list

44 Masonry cavity walls and plasterboard laminate

46 Solid masonry walls (internal)

48 Solid masonry walls (external)

50 Timber frame wall lining

52 Single timber frame wall lining and dormer cheeks

54 Timber frame wall sheathing

56 Steel stud framed walls

58 Rainscreen cladding

60 ▶ Insulation solutions for floors62 Calculating the P/A ratio

64 Concrete slab floors

66 Beam and block floors

68 Suspended timber floors

70 Underfloor heating

72 Concrete soffit floors

74 ▶ Garage conversions76 ▶ Loft conversions78 ▶ General information

Contents

4 | T: 0901 996 0100* | celotex.co.uk

As part of the Climate Change Act, the UK continues to

lead the attack on global warming. As part of this

agreement, an 80% reduction in CO2 emissions is now a

legally binding target and must be achieved by 2050.

Part L 2010 came into effect from 1st October 2010

calling for a 25% reduction in CO2 emissions compared

to the 2006 regulations. Whilst compliance is calculated

through a whole building approach and a variety of

different measures, improvements to the

recommended U-value targets for 2010 show that

adopting a fabric first approach is the single most

important measure for reducing CO2 emissions.

The requirements of Part L are best achieved by

meeting U-values that are more demanding than

previously seen. The use of high performance insulation

materials within the building fabric is one of the most

proven solutions for helping gain compliance.

Celotex PIR insulation with a thermal conductivity value

as low as 0.022W/mK can help meet lower U-values,

prevent heat loss and maximise thermal performance.

Typically, this is achieved with a thinner solution

compared to other insulation products.

Alongside other legislative frameworks such as BREEAM

and the Code for Sustainable Homes, as well as ongoing

programmes within the existing stock sector, Part L

2010 will provide a benchmark for ‘future-proofing’ the

energy performance of homes and buildings.

With a premium product range suitable for pitched and

flat roofs, walls and floors, the specification and use of

Celotex will deliver even lower U-values and help meet

the targets of Part L 2010.

Please see page 5 for information regarding the new

U-values required for Part L 2010.

For further information on Part L 2010 or to discover

more about Celotex’ sustainability credentials, please

visit the website at celotex.co.uk

For illustration purposes only.

Part L 2010 and The Road to Zero Carbon

T: 0901 996 0100* | celotex.co.uk | 5

England and Wales Approved Document L1A (2010) – new dwellings.Elemental U-values – indicative only For regulation compliance, new dwellings must

achieve a CO2 Target Emissions Rate (TER). This is

unique to each dwelling design and is calculated

using Standard Assessment Procedure (SAP) 2009.

The TER is more easily achieved by specifying

high standards of fabric insulation, resulting in

low U-values.

The U-values shown indicate the standard of

insulation required to meet typical dwelling TERs

and are given for guidance purposes only.

England and Wales Approved Document L1B (2010) – work in existing dwellings. Elemental U-valuesUnder the new regulations existing dwellings do not

have to meet a TER. Instead, they have to meet so

called ‘elemental U-values’ which refers to target

figures for individual floor, wall and roof elements of

the building.

These values are shown in the illustration to the right.

Scotland Domestic Technical Handbook – Section 6: Energy.Elemental U-valuesUnder the Scottish regulations, dwellings do not

have to meet a target TER (unless requested by local

authority). Instead they have to meet so called

‘elemental U-values’ which refers to target figures

for individual floor, wall and roof elements of

the building.

These values are shown in the illustration to the right.

0.18

0.16

0.18

new extension

0.16

0.25 unheatedspace

loft

0.250.30

0.28

0.22

0.30

existing dwelling

0.13

0.13

0.19

0.19 unheatedspace

loft

0.130.19

0.15

0.15

0.13 - 0.15

0.13 - 0.15

0.13 - 0.15

0.15 - 0.20

0.20-

0.250.20

- 0.25

unheatedspace

loft

0.15 - 0.20

6 | T: 0901 996 0100* | celotex.co.uk

With over eighty years as the insulation specialists,

Celotex with its extensive product range, leading

technical and manufacturing expertise and high levels

of customer service, remain the brand leading provider

of PIR insulation.

We remain focused and committed to insulation

innovation as well as enhancing our products and

services to help meet the requirements of Part L 2010

and other carbon reduction programmes.

Why Celotex PIR?As one of the leading investors within the insulation

sector, Celotex PIR has a considerable advantage over

many other insulation providers. This is reflected

through our in-depth knowledge of manufacturing

techniques and recent achievements in product

performance.

Celotex PIR insulation offers:

▶ Products with a thermal conductivity as low as

0.022W/mK offering some of the thinnest

possible solutions and even lower U-values

▶ Better thermal efficiency per mm than many

other insulation materials

▶ An A+ rating when compared to the BRE

Green Guide 2008

▶ A lower environmental impact than other

typical PIR manufacturers

▶ Products with Class O fire performance

▶ The broadest range of PIR thicknesses from

12mm to 200mm

▶ An expansive product range suitable for

pitched and flat roofs, walls and floors

▶ Industry leading technical support via the

Celotex Technical Centre

Celotex product rangeAs part of our process for continuous product

improvement, we have yet again broken through the

technology barrier.

We have improved the thermal performance of most of

our products which now offer a lower lambda value of

0.022W/mK. Resulting in higher R-values for our boards

these improvements will help you achieve thinner

solutions and even lower U-values.

Celotex offers premium performance options through

Celotex FR4000 & CG4000, the broadest range of

product thicknesses from 12mm to 200mm with our

TB4000, GA4000 & XR4000 as well as specialist product

solutions for cavity wall, underfloor heating, dry lining,

concrete soffit floor and flat roofing applications.

celotex.co.uk Further information on all Celotex products can be

found from page 8. Or why not download the

information from the Celotex website? Product and

application literature are available free of charge. The

site contains the popular on-line U-value calculator

and you can even purchase SAP calculations and

Energy Performance Certificates. Whatever your

requirement, you’ll find everything you need from the

insulation specialists.

Celotex – we know insulation inside and out

T: 0901 996 0100* | celotex.co.uk | 7

The Celotex Technical Centre With outstanding levels of technical expertise and

personal assistance, the Celotex Technical Centre will

provide you with all of the guidance and support you

need when specifying and installing Celotex products.

The Centre is on hand to provide assistance on any of

the following matters:

▶ Part L 2010

▶ Code for Sustainable Homes & BREEAM

▶ U-value calculations

▶ Application and installation guidance

▶ Condensation risk analysis

▶ Technical approvals

▶ Environmental and sustainability credentials

▶ SAP calculations

▶ Energy Performance Certificates

SAP calculationsSAP is the Government’s Standard Assessment

Procedure for calculating a dwelling’s energy rating.

SAP is a compulsory element of Part L 2010, meaning

that all new homes are required to have a SAP rating.

SAP is a whole house energy calculation and looks at

the size of the property, type and size of doors and

windows and the provision of heating, lighting and

hot water.

SAP is used to produce an Energy Performance

Certificate (EPC) for a new home. These are required by

law to be provided to owners or tenants of new homes.

Energy Performance Certificates (EPCs)EPCs record how energy efficient a property is as a

building and provide performance ratings from A-G.

EPCs are issued after the property is built, and are

produced using standard methods and assumptions

about energy usage so one building can be directly

compared with another of the same type. This allows

prospective occupiers to consider energy efficiency and

fuel costs before committing to a property. EPCs are

legally required for all homes, whenever they are built,

rented or sold. As legal documents, EPCs can only be

produced by accredited energy assessors.

With its own in-house On Construction Energy

Assessors, the Celotex Technical Centre can provide you

with all your SAP Calculations and Energy Performance

(EPC) Certificates, including a Recommendation Report

offering advice and suggestions on how to further

improve energy efficiency.

To provide the maximum level of assistance, the Celotex

Technical Centre is open from 8am to 5.15pm. For

further information on any of the services contact the

Centre via celotex.co.uk or call 0901 996 0100*

8 | T: 0901 996 0100* | celotex.co.uk

Product descriptions

Celotex FR4000 is our premium performance PIR

solution. Through ongoing product innovation and

breakthrough design techniques, FR4000 offers

enhanced thermal performance as well as Class O fire

performance throughout the entire product.

FR4000 is targeted specifically at pitched roof, wall and

floor applications and is available in a broad range of

thicknesses, from 25mm – 150mm. Celotex FR4000

delivers superior insulation performance compared

with typical PIR products.

Always install Celotex FR4000 in accordance with the

instructions supplied by Celotex.

Standard board dimensions1200mm x 2400mm.

Physical propertiesThermal resistance (R) values for Celotex products are

declared in accordance with BS EN 13165. These

R-values equate to a Thermal Conductivity (λ) value of

0.022W/mK.

Fire resistanceIn accordance with the results of BS 476 Parts 6 & 7,

FR4000 complies with the requirements of Class O as

defined in the Building Regulations.

Celotex CG4000 is our premium performance PIR

solution specifically designed for partial fill cavity wall

applications. As well as enhanced thermal performance,

CG4000 offers Class O fire performance throughout the

entire product.

CG4000 is available in a range of thicknesses from

40mm – 100mm and delivers superior insulation

performance compared with typical PIR products.

Always install Celotex CG4000 in accordance with the






0.022W/mK.

Fire resistanceIn accordance with the results of BS 476 Parts 6 & 7,

CG4000 complies with the requirements of Class O as

defined in the Building Regulations.

Product rangeProduct code Thickness (mm) R-value (m2K/W)

CG4040 40 1.80

CG4050 50 2.25

CG4060 60 2.70

CG4075 75 3.40

CG4085 85 3.85

CG4090 90 4.05

CG4100 100 4.50


FR4025 25 1.10

FR4050 50 2.25

FR4060 60 2.70

FR4070 70 3.15

FR4075 75 3.40

FR4080 80 3.60

FR4090 90 4.05

FR4100 100 4.50

FR4110 110 5.00

FR4120 120 5.45

FR4130 130 5.90

FR4140 140 6.35

FR4150 150 6.80

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Celotex SL4000 is a high performance thermal

insulation board where premium Celotex FR4000

insulation is bonded to a layer of 6mm calcium silicate.

Celotex SL4000 is specifically targeted at concrete soffit

floor applications such as underground car parks

situated beneath habitable buildings e.g. offices or

residential flats.

SL4000 utilises the unrivalled insulation properties of

Celotex FR4000 with calcium silicate providing

additional fire performance and impact resistance. The

calcium silicate laminate provides a decorative finish

with no requirement for on-site decoration, and as a

two in one product assists the installer with reduced

installation times.

Always install Celotex SL4000 in accordance with the





R-values equate to a Thermal Conductivity (λ) of the

insulation component of 0.022W/mK.

Fire resistance In accordance with the results of BS 476 Parts 6 & 7,

both the insulation and calcium silicate used in SL4000

comply with the requirements of Class O as defined in

the Building Regulations.

Celotex TB4000 is a thin, foil faced insulation board

with thicknesses ranging from 12mm - 45mm. Celotex

TB4000 is designed to provide simple solutions to

overcome localised thermal bridges. Celotex is unique

in being able to offer boards as thin as 12mm to the

market for this purpose.

Always install Celotex TB4000 in accordance with the


Standard board dimensions1200mm x 2400mm (with grid markings to assist

installation).




0.022 W/mK.

Fire resistanceSurface spread of flame in accordance with

BS 476 Part 7 = Class 1.

Product range CombinedProduct code Thickness (mm) R-value (m2K/W)

SL4056 50 + 6 2.25

SL4066 60 + 6 2.70

SL4076 70 + 6 3.15

SL4086 80 + 6 3.65

SL4096 90 + 6 4.10

SL4106 100 + 6 4.55

SL4116 110 + 6 5.00

SL4126 120 + 6 5.45


TB4012 12 0.50

TB4020 20 0.90

TB4025 25 1.10

TB4030 30 1.35

TB4035 35 1.55

TB4040 40 1.80

TB4045 45 2.00

Celotex GA4000 has long been at the heart of the

Celotex range, providing a range of thermal insulation

solutions to the builder. GA4000 features low emissivity

aluminium foil facings and is suitable for a range of

applications including pitched and flat roofs, walls and

floors.

Always install Celotex GA4000 in accordance with the



installation).



R-values equate to a Thermal Conductivity (λ) value

of 0.022 W/mK.

Fire resistanceSurface spread of flame in accordance with

BS 476 Part 7 = Class 1 (50 - 90mm only).

Celotex XR4000 is manufactured on our state-of-the-

art restrained rise production line featuring our own

unique jointless lay down technology. This technology

enables us to offer thicker boards with no visible seams

in the PIR foam core. XR4000 enables users to achieve

lower U-values with a single layer of insulation than has

previously been possible. This helps meet present and

future regulations including Part L, BREEAM and the

Code for Sustainable Homes. XR4000 is appropriate for

use in floor, wall and roof applications.

Always install Celotex XR4000 in accordance with the



installation).




of 0.022 W/mK.

10 | T: 0901 996 0100* | celotex.co.uk


XR4110 110 5.00

XR4120 120 5.45

XR4130 130 5.90

XR4140 140 6.35

XR4150 150 6.80

XR4165 165 7.50

XR4200 200 9.05


GA4050 50 2.25

GA4055 55 2.50

GA4060 60 2.70

GA4065 65 2.95

GA4070 70 3.15

GA4075 75 3.40

GA4080 80 3.60

GA4085 85 3.85

GA4090 90 4.05

GA4095 95 4.30

GA4100 100 4.50


T: 0901 996 0100* | celotex.co.uk | 11

Celotex CW4000 provides a simple insulation solution

for partial fill cavity wall applications. With excellent

thermal properties, the boards also offer low emissivity

aluminium foil facings providing enhanced thermal

performance within cavity air spaces.

Always install Celotex CW4000 in accordance with the



installation).




of 0.022 W/mK.

Fire resistanceSurface spread of flame in accordance with BS 476 Part

7 = Class 1 (25 - 90mm only).

Celotex PL4000 is a high performance thermal

insulation board where the PIR insulation is bonded to

a 12.5mm sheet of tapered edge plasterboard.

Celotex PL4000 is suitable for both direct bonding and

mechanically fixed applications and allows the user to

install both the insulation and plasterboard in one

operation thereby reducing installation times.

Celotex PL4000 is suitable as the underneath layer of

insulation in both pitched and flat roof ‘between and

under’ applications as well as in internal dry lining

applications. It can be used in new build applications as

well as providing the perfect solution for refurbishment

projects where little or no insulation exists.

Always install Celotex PL4000 in accordance with the



installation).




0.022W/mK (insulation only).

Fire resistanceThe plasterboard used in PL4000 is defined as Class O in

accordance with the Building Regulations.

Product range CombinedProduct code Thickness (mm) R-value (m2K/W)

PL4025 25 + 12.5 1.20

PL4040 40 + 12.5 1.85

PL4045 45 + 12.5 2.10PL4050 50 + 12.5 2.35

PL4055 55 + 12.5 2.55

PL4060 60 + 12.5 2.80

PL4065 65 + 12.5 3.00


CW4025 25 1.10

CW4040 40 1.80

CW4045 45 2.00

CW4050 50 2.25

CW4055 55 2.50

CW4060 60 2.70

CW4065 65 2.95

CW4070 70 3.15

CW4075 75 3.40

CW4080 80 3.60

CW4085 85 3.85

CW4090 90 4.05

CW4100 100 4.50

12 | T: 0901 996 0100* | celotex.co.uk

Celotex TC3000 is a purpose designed insulation

board for use within built-up flat roofing applications

including hot applied bituminous, mastic asphalting

and torch-on systems. It provides a quick and easy way

to achieve effective thermal insulation in flat roofing

structures.

TC3000 features bitumen polypropylene fleece facers

on both sides and comes available in an easy to handle

board size and a range of thicknesses from 50mm to

150mm.

Always install Celotex TC3000 in accordance with the





R-values equate to a Thermal Conductivity (λ) of:

0.027W/mK for product thicknesses under 80mm

0.026W/mK for product thicknesses between 80-119mm

0.025W/mK for product thicknesses of 120mm or over.

Celotex EL3000 is a purpose designed insulation board

for use in built-up flat roofing applications, including

hot-applied bituminous and mastic asphalt

waterproofing systems and fully adhered single-ply

membranes.

Celotex EL3000 features a coated glass tissue facer,

perforated on one side for use in bitumen-based built-

up applications, whilst the reverse unperforated facer is

suitable for single-ply membrane applications. Celotex

EL3000 is available in a range of thicknesses allowing

you to achieve U-values with minimum thickness.

Always install Celotex EL3000 in accordance with the


Standard board dimensions1200mm x 600mm (120mm board thicknesses is also

available in board dimensions of 1200mm x 2400mm).



R-values equate to a Thermal Conductivity (λ) value of:

0.027W/mK for product thickness under 80mm

0.026W/mK for product thickness between 80-119mm

0.025W/mK for product thickness of 120mm or over.

Fire resistance External roof exposure = Ext. FAB in accordance with

BS 476-3.


TC3050 50 1.85

TC3100 100 3.80

TC3120 120 4.80

TC3130 130 5.20

TC3140 140 5.60

TC3150 150 6.00


EL3050 50 1.85

EL3100 100 3.80

EL3120 120 4.80

EL3130 130 5.20

EL3140 140 5.60

EL3150 150 6.00


T: 0901 996 0100* | celotex.co.uk | 13

Celotex TA4000 is a purpose designed insulation board

for use with mechanically fixed and ballasted single-ply

weathering systems. It provides a quick and easy way to

achieve effective thermal insulation in flat roofing

structures. These boards all feature the unique jointless

lay down system to improve the flatness of the product.

Celotex TA4000 performs to a compressive strength of

150kPa giving improved resistance to site traffic during

installation and is available in a range of thicknesses.

Always install Celotex TA4000 in accordance with the



installation).


declared in accordance with BS EN 13165. These R-values

equate to a Thermal Conductivity (λ) value of 0.022

W/mK.

Celotex TD4000 provides a quick and easy way to

achieve effective thermally insulated roof decks for

building structures such as small extensions or garage

roofs where there will be only occasional trafficking.

These products feature a foil faced insulation board, to

give the best insulation value possible, bonded to a

facing of 5.5mm WBP ply. This allows the user to install

the roof structure in one operation since the product

provides the deck, insulation and vapour control layer

thereby considerably reducing installation times ahead

of weatherproofing.

Always install Celotex TD4000 in accordance with the



installation).




0.022 W/mK (insulation only).

Fire resistance (insulation only)Surface spread of flame in accordance with BS 476

Part 7 = Class 1 (TD4096 only).

Product rangeThickness (mm) Combined

Product code Insulation + ply R-value (m2K/W)

TD4096 90 + 5.5 4.10

TD4106 100 + 5.5 4.55

TD4116 110 + 5.5 5.00

TD4126 120 + 5.5 5.45


TA4085 85 3.85

TA4090 90 4.05

TA4100 100 4.50

TA4115 115 5.20

TA4125 125 5.65

TA4135 135 6.10

14 | T: 0901 996 0100* | celotex.co.uk

Celotex FF4000 is manufactured on our state-of-the-

art restrained rise production line featuring our own

unique jointless lay down technology. This technology

enables us to offer thicker boards with no visible seams

in the foam core. This foil faced product is targeted

specifically at ‘under screed’ floor applications —

including underfloor heating systems — where the

higher density and compressive strength of the board

prove valuable to the installer.

Always install Celotex FF4000 in accordance with the



installation).




0.022 W/mK.

Celotex Insulation TapeFor the sealing of joints when installing foil-faced

Celotex PIR insulation boards. This 3 in 1 product

prevents air leakage, completes the vapour control layer

and maximises thermal performance. Celotex Insulation

Tape is suitable for a range of applications, including

walling systems and pitched and flat roofing

applications.

Roll size48mm x 55metres.

Celotex Insulation SawWhen cutting Celotex PIR insulation boards, use theCelotex Insulation Saw. The saw is the only one on themarket specifically for cutting PIR insulation boards.Featuring fine, hard point teeth, it is proven todramatically reduce the amount of dust created whencutting Celotex insulation boards as well as reducingcutting time.

Physical propertiesSaw length: 350mm

Saw weight: 225grams

Tooth Protector Clip included

Celotex HoodsThe Celotex Hoods are a branded polythene

weatherproofing hood, which allow for the external

storage and protection of Celotex products. The Hoods

remove the need for unsuitable covering methods such

as tarpaulins and rope which can damage the boards.

They are also easy to use and are suitable for repeat use;

an ideal storage solution when inside space is limited.

Physical propertiesCovers Celotex pack size of 1200mm (D) x 2400mm (W)x 1250mm (H).

Supplied on a roll, 25 hoods per roll, perforated for easy use.

For further information about these accessory productsor for a list of suppliers of ancillary components for floor,wall and roof applications, visit celotex.co.uk or contactour Sales Department.


FF4050 50 2.25

FF4070 70 3.15

FF4075 75 3.40

FF4085 85 3.85

FF4090 90 4.05

FF4100 100 4.50

FF4125 125 5.65


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Celotex Insulation Clip

IntroductionThe Celotex Insulation Clip has been designed to enable

insulation boards to be installed between timber joists or

rafters quickly and without the need for nails, screws or

battens. They provide a permanent way of securing the

Celotex insulation with as little fuss as possible.

The clip should be used in situations where the insulation is

being installed from above or below, for example when

fitting between joists in a suspended timber floor.

Using the clip ensures that the insulation will be held firmly

in place once installed in the correct manner.

Installation guidelines▶ The joists / rafters should be installed in the conventional

manner in accordance with the Building Regulations.

▶ Cut the Celotex insulation boards to the width of the

space between the joists / rafters ensuring a straight

edge to the board to enable a tight interference fit.

▶ Push the insulation clips into the board at 1000mm

intervals with the two prongs piercing the exposed foam

down the long edge of the board (see fig.1).

▶ Start the clips in between the joists / rafters and push the

board into place (see fig.2). This should be a tight fit to

minimise heat loss through the gaps between the joist /

rafter and insulation board.

▶ Push the board fully home so that the base of the

insulation clip is level with the face of the joist / rafter

(see fig.3).

▶ If additional board security is required, for example where

there is no lining below the joists / rafters, nail through

the base of the clip directly into the joist (see fig.4).

▶ Where additional insulation or plasterboard is required

below the joists / rafters, continue as in the Celotex

literature for that application (see fig.5).

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 1

16 | T: 0901 996 0100* | celotex.co.uk

Insulation solutions for pitched roofs

Kentgate | Cumbria

T: 0901 996 0100* | celotex.co.uk | 17

Insu

lation

solu

tion

s fo

r pitch

ed ro

ofs

INCLUDING:

▶ Pitched roof sarking

▶ Insulation between and over rafters

▶ Insulation between rafters

▶ Insulation between and under rafters

18 | T: 0901 996 0100* | celotex.co.uk

Thickness(mm)

---

22

25See below

150-

12.5-

Example U-value calculation: pitched roof sarking

Thickness(mm)

120110100908075706560555045

U-value(W/m2K)

0.140.140.150.160.170.180.190.200.210.220.230.25

Construction

Outside surface resistanceTiling including batten spaceBreather membraneCavity / counter battenCelotex TB4000 between 47 x 47 counter battens @ 400 ctrsVariable layerCavity (low emissivity) rafter space (11.7% brg)Polythene 1000 gauge, VCLPlasterboardInside surface resistance

Variable Layer

Celotex XR4000 over rafterCelotex XR4000 over rafterCelotex XR4000 over rafterCelotex XR4000 over rafterCelotex XR4000 over rafterCelotex XR4000 over rafterCelotex XR4000 over rafterCelotex GA4000 over rafterCelotex GA4000 over rafterCelotex GA4000 over rafterCelotex GA4000 over rafterCelotex GA4000 over rafterCelotex GA4000 over rafterCelotex GA4000 over rafterCelotex GA4000 over rafter

Thickness(mm)

---

2225

See below150

-12.5

-

U-value: For U-values see variable layer list

Thickness(mm)20016515014013012011010095908580757065

U-value(W/m2K)

0.090.110.120.120.130.140.140.150.160.170.170.170.180.190.20

Pitched roof sarking

Use Celotex GA4000 and Celotex XR4000 high performance

thermal insulation in pitched roof sarking applications to

minimise insulation thickness and give the following benefits:

▶ Highly efficient ‘warm roof’ insulation over rafters

▶ Provides reliable long term energy savings for buildings

▶ Low emissivity foil facers give improved thermal

insulation performance within cavity air spaces

▶ Eliminates thermal bridging

▶ Optional single layer system

▶ Ideal for new build or major refurbishment projects

▶ Air-tight construction method

T: 0901 996 0100* | celotex.co.uk | 19

▶ Note that specific fixing requirements should be

determined for each roof, taking into account roof

design and location.

▶ Fix a treated timber stop batten equal in thickness to

the Celotex insulation across the rafters at the eaves.

Butt boards directly against this batten.

▶ Install Celotex insulation boards with the long sides

parallel to the rafter lines with both edges

supported by rafters.

▶ For optimum thermal performance, the unprinted

foil surface should face adjacent air cavities.

▶ Cut the boards using the Celotex Insulation Saw to

rake and splay at ridge and verges to ensure close

butted joints.

▶ Use large headed nails to fix boards in place

temporarily until permanently secured by counter

battens.

▶ Position a preservative-treated timber counter

batten (minimum 38mm x 50mm) over the

insulation on the line of each rafter. Nail the lower

end of each counter batten directly into the stop

batten.

▶ Calculate the length of the stainless steel helical

spike fixings required by adding together the

counter batten depth, the insulation thickness and

depth of penetration required to the rafter (usually

minimum 38mm).

▶ Stainless steel helical spikes have been specifically

developed for ‘warm’ pitched roofs and are

especially appropriate for use with pre-trussed rafter

constructions, allowing a much thinner gauge of

fastener to be used, thus reducing the risk of

splitting timber battens or rafters.

▶ Fix at maximum 400mm centres along the counter

batten. Pre-drill pilot holes in the counter battens to

ensure ease of nailing and to reduce the possible

splitting of the timber.

▶ If using a two layer system, cut a second layer of

board with the Celotex Insulation Saw (the board

should be at least 13mm less than the counter

batten thickness allowing for the breather

membrane to sag) to fit between the counter

battens.

▶ Drape a breather membrane over the counter

battens and secure with tile battens.

▶ Fix the tile battens to the counter batten at an

appropriate gauge to suit the slates or tiles selected.

▶ A variety of eaves and verge details may be achieved

with this system. Eaves and soffit ventilators are not

generally required.

▶ A vapour control layer (VCL) should be installed to

the underside of the rafters.

▶ Finish with plasterboard or other suitable sheet

material fixed to the rafters.

▶ Where exposed rafters are required, plasterboard

(or any other suitable decorative board) may be laid

over the rafters before fixing the insulation. Select

longer fasteners to suit. Plasterboard should be

protected from rain during the installation. A

polythene vapour control layer (VCL) must be

installed directly over the plasterboard.

Installation guidelines

also suitable for this application

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Construction

Outside surface resistanceTiling including batten spaceCounter battenBreather membraneVariable layerCelotex TB4000 between rafters @ 400 ctrs (11.7% brg)Cavity (low emissivity) rafter spacePolythene 1000 gauge, VCLPlasterboardInside surface resistance

Variable Layer

Thickness(mm)

--

38-

See below40

110-

12.5-

Celotex XR4000 over rafter







Celotex GA4000 over rafter








Thickness(mm)200

165

150

140

130

120

110

100

95

90

85

80

75

70

65

U-value(W/m2K)

0.09

0.11

0.12

0.12

0.13

0.14

0.14

0.15

0.15

0.16

0.17

0.17

0.18

0.19

0.20


Use Celotex GA4000 and Celotex XR4000 high

performance thermal insulation in pitched roof between

and over rafter applications to minimise insulation thickness

and give the following benefits:

▶ Ideal for use where headroom is limited


▶ Creates a warm, habitable roof space

▶ No need to insulate water pipes and tanks

▶ Suitable for new build and major refurbishment projects

▶ Minimised additional loading to the structure

Example U-value calculation: between and over rafters

Insulation between and over rafters

T: 0901 996 0100* | celotex.co.uk | 21

Insulation over the rafters

▶ Note that specific fixing requirements should be

determined for each roof, taking into account roof

design and location.

▶ Fix a treated timber stop batten equal in thickness

to the Celotex insulation across the rafters at the

eaves. Butt boards directly against this batten.

▶ Install Celotex insulation boards with both edges

supported by the rafters.

▶ Cut the boards using the Celotex Insulation Saw to

rake and splay at ridge and verges to ensure close

butted joints.

▶ Use large headed nails to temporarily fix board in

place, until permanently secured by counter

battens.

▶ Install a breather membrane over the insulation.

▶ Position a preservative-treated timber counter

batten (minimum 38mm x 50mm) over the breather

membrane and insulation on the line of each rafter.

Nail the lower end of each counter batten directly

into the stop batten.

▶ Calculate the length of the suitable fixings required

by adding together the counter batten depth, the

insulation thickness and depth of penetration

required to the rafter (usually minimum 38mm).

▶ Fix at maximum 400mm centres along the counter

batten. Pre-drill pilot holes in the counter battens to

ensure ease of nailing and to reduce the possible

splitting of the timber.

▶ Fix the tile battens to the counter battens at an

appropriate gauge to suit the slates or tiles selected.

Insulation between the rafters

▶ For optimum thermal performance the unprinted

foil surface should face the rafter air cavity.

▶ Accurately measure the width to be filled between

the inside face of the rafters, prior to cutting the

board.

▶ Use the Celotex Insulation Saw to cut the Celotex

board at a slight angle, making the board width

slightly oversized on one surface to achieve a

‘friction fit’.

▶ Push the board into the void between the rafters

until it is tight against the underside of the first layer

of insulation.

▶ To hold the boards in place, use battens along the

side of the rafters.

▶ Tightly fit the insulation to the ridge plate and carry

over and tightly butt the wall plate at eaves.


the underside of the rafters. A polythene sheet of

higher vapour resistance is recommended for high

humidity areas such as kitchens or bathrooms.

▶ Finish with plasterboard or other suitable sheet

material, fixed to the rafters.

NB: This solution is not suitable for exposed rafters.

Where exposed rafters are required, please refer to

the pitched roof sarking application on pages

18 and 19.



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Construction

Outside surface resistanceTiling including batten spaceBreather membraneLow E cavity, remainder of rafter depthVariable layer (for between rafters)Polythene, 1000 gauge VCLPlasterboardInside surface resistanceVariable Layer

Celotex XR4000 @ 400 ctrsCelotex XR4000 @ 400 ctrsCelotex XR4000 @ 400 ctrsCelotex XR4000 @ 400 ctrsCelotex XR4000 @ 600 ctrsCelotex XR4000 @ 600 ctrsCelotex XR4000 @ 600 ctrsCelotex XR4000 @ 600 ctrsCelotex XR4000 @ 600 ctrs

200 mm deep rafters 175 mm deep rafters 150 mm deep raftersThickness (mm) Thickness (mm) Thickness (mm)

- - -- - -- - -

Various Various VariousSee below See below See below

- - -12.5 12.5 12.5

- - -Thickness U-value U-value U-value

(mm) (W/m²K) (W/m²K) (W/m²K)200 0.17* - -165 0.18 0.19 -150 0.19 0.20 -140 0.20 - -200 0.15* - -165 0.16 0.17 -150 0.18 0.18 0.19*140 0.18 0.19 0.19130 0.19 0.20 0.20

Example U-value calculation: unventilated between rafters

* = Counter batten over membrane - see installation guidelines

Insulation between rafters

Use Celotex XR4000 high performance thermal insulation in

between rafter applications to minimise insulation thickness


▶ Optional single-layer insulation reduces cutting


▶ Easy to dry line with plasterboard once installed

▶ Dimensionally stable

▶ No loss of internal headroom

▶ Ideal for loft conversions / room in roof applications

T: 0901 996 0100* | celotex.co.uk | 23


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▶ Make sure there is enough rafter depth to

accommodate not only the thickness of the Celotex

insulation, but also a minimum 20mm drape space

for the breathable membrane.

▶ Fix battens to the inside face of the rafters, to ensure

that the drape space is maintained.

▶ Alternatively, counter battens can be fixed over the

breathable membrane to provide a channel for

moisture run off. The whole depth of the rafter can

then be filled with insulation.

▶ All details are to be in accordance with the

membrane manufacturers details.

▶ Measure the space to be filled between the inside

face of the rafter prior to cutting the board.

▶ Use the Celotex Insulation Saw to cut the boards at

a slight angle, making the board width slightly

oversized on one surface to achieve a ‘friction fit’.

▶ Push the boards into the void between the rafters until

they are tight up to the battens or the membrane,

ensuring that lateral joints are closely butted.

▶ Tightly fit the insulation to the ridge plate and carry

over and tightly butt the wall plate at eaves.


the underside of the rafters. A polythene sheet of

higher vapour resistance is recommended for high

humidity areas such as kitchens or bathrooms.

▶ Complete the internal finish with plasterboard or

other suitable sheet material.

24 | T: 0901 996 0100* | celotex.co.uk

Use a combination of Celotex GA4000 or Celotex XR4000with Celotex PL4000 high performance plasterboard

thermal laminate in pitched roof between and under rafter

applications to minimise insulation thickness and give the

following benefits:

▶ Provides both the below rafter insulation and

plasterboard in one product helping reduce

installation time

▶ Offers the installer maximum flexibility and installation

speed due to the tapered edge plasterboard

▶ Ideal for use with shallow rafters


▶ Minimised additional loading to the structure

▶ Dimensionally stable

▶ Ideal for loft conversions / room in roof applications

▶ Upgrade existing ceilings to current standards

Example U-value calculation: unventilated between and under raftersConstruction

Outside surface resistance

Tiling including batten space

Breather membrane

Low E cavity between rafters (11.7% brg)

Celotex between rafters @ 400 ctrs (11.7% brg)

Variable layer (for below rafters)

Inside surface resistance

Variable Layer

Celotex PL4000

Celotex PL4000

Celotex PL4000

Celotex PL4000

Celotex PL4000

Celotex PL4000

Celotex PL4000

GA = GA4000 XR = XR4000 Low E = Low emissivity

100mm 125mm 150mm 175mmdeep rafters deep rafters deep rafters deep rafters

Thickness Thickness Thickness Thickness (mm) (mm) (mm) (mm)

- - - -

- - - -

- - - -20 25 30 25

GA4080 GA4100 XR4120 XR4150

See below See below See below See below

- - - -

Thickness U-value U-value U-value U-value(mm) (W/m²K) (W/m²K) (W/m²K) (W/m²K)

65 + 12.5 0.16 0.14 0.13 0.12

60 + 12.5 0.16 0.15 0.13 0.12

55 + 12.5 0.17 0.15 0.14 0.12

50 + 12.5 0.18 0.16 0.14 0.13

45 + 12.5 0.18 0.16 0.15 0.13

40 + 12.5 0.19 0.17 0.15 0.14

25 + 12.5 - 0.20 0.17 0.15

Insulation between and under rafters

Construction

Outside surface resistanceTiling including batten spaceSarking feltVentilated cavityCelotex between rafters @ 400 ctrs (11.7% brg)Variable layer (for below rafters)Inside surface resistance

Variable Layer

Celotex PL4000Celotex PL4000Celotex PL4000Celotex PL4000Celotex PL4000Celotex PL4000Celotex PL4000

GA = GA4000 XR = XR4000 Low E = Low emissivity

100mm 125mm 150mm 175mmdeep rafters deep rafters deep rafters deep rafters


- - - -- - - -- - - -

50 50 50 55

GA4050 GA4075 GA4100 XR4120 See below See below See below See below

- - - -


65 + 12.5 0.20 0.17 0.15 0.1460 + 12.5 - 0.18 0.16 0.1455 + 12.5 - 0.19 0.16 0.1550 + 12.5 - 0.20 0.17 0.1545 + 12.5 - - 0.18 0.1640 + 12.5 - - 0.19 0.1725 + 12.5 - - - 0.19

T: 0901 996 0100* | celotex.co.uk | 25

TB4000


Example U-value calculation: ventilated between and under rafters

Installation guidelines: ventilated

▶ Make sure there is enough rafter depth to


insulation but also a 50mm ventilated airspace

above the boards.

▶ Fix battens to the inside face of the rafter so that the

bottom of the batten is 50mm below the sarking felt.

Installation guidelines: unventilated

▶ Install the breather membrane over the rafters. Fix

battens to the side of the rafters to allow the

membrane to sag between the rafters. Alternatively,

fix counter battens over the membrane, leaving the

entire rafter depth to be filled with insulation. All

details are to be in accordance with the membrane

manufacturer’s recommendations.

Installation guidelines: ventilated & unventilated


face of the rafter prior to cutting the board.

▶ Use the Celotex Insulation Saw to cut the boards at

a slight angle, making the board width slightly

oversized on one surface to achieve a ‘friction fit’.

▶ Push the boards into the void between the rafters

until they are tight up to the battens or the

membrane, ensuring that lateral joints are closely

butted. Secure Celotex PL4000 to the underside of

the rafters with broad-headed clout nails.

▶ Joints between boards must be tightly butted,

taped and jointed using appropriate tape and

jointing material to create the vapour control layer.


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Insulation solutions for flat roofs

BSF Scheme | Knowsley

T: 0901 996 0100* | celotex.co.uk | 27

INCLUDING:

▶ Built-up flat roofing applications

▶ Single-ply flat roofing applications

▶ Flat roof insulating deck

▶ Insulation between and under joists

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Construction Concrete Concrete Steel Steel Timber TimberDeck Deck Deck Deck Deck DeckFully Mechanically Fully Mechanically Fully Mechanically

Bonded Fixed Bonded Fixed Bonded FixedThickness Thickness Thickness Thickness Thickness Thickness

(mm) (mm) (mm) (mm) (mm) (mm)Outside surface resistance - - - - - -Built-up roofing 12 12 12 12 12 12Variable layer See below See below See below See below See below See belowPolythene 1000 gauge, VCL - - - - - -Concrete deck 250 250 n/a n/a n/a n/aSteel deck n/a n/a 1.5 1.5 n/a n/aTimber deck plywood n/a n/a n/a n/a 19 19Cavity between joist at 11.7% bridging n/a n/a n/a n/a 150 150Plasterboard n/a n/a n/a n/a 12.5 12.5Inside surface resistance - - - - - -

Variable Layer Thickness U-value U-value U-value U-value U-value U-value(mm) W/m2K W/m2K W/m2K W/m2K W/m2K W/m2K

Celotex EL3000/TC3000 150 0.16 0.18 0.16 0.19 0.15 0.18Celotex EL3000/TC3000 140 0.17 0.19 0.17 0.20 0.16 0.19Celotex EL3000/TC3000 130 0.18 0.20 0.18 0.20 0.17 0.20Celotex EL3000/TC3000 120 0.19 0.22 0.20 0.22 0.18 0.21

Celotex EL3000/TC3000 100 0.24 - 0.25 - 0.22 0.25

Example U-value calculation: warm flat roof - built-up roofing

Use Celotex EL3000 or Celotex TC3000 high

performance insulation in built-up flat roofing

applications. Celotex EL3000 and Celotex TC3000 are

both suitable for use in hot applied bituminous and

mastic asphalt waterproofing systems. Celotex TC3000 is

also suitable for use in torch-on flat roofing applications.

When designing a flat roof using Celotex EL3000 or

TC3000 boards, three basic principles apply:

1. Design to a fall of 1:80, 1:60 or 1:40 as appropriate

to the weathering system, type of deck and

construction tolerances.

2. Have due regard for the use and design of the

building and the need to ensure that the design

will not allow for a build up of moisture below the

waterproofing membrane.

3. Provide adequate protection for both insulation

and waterproofing if significant foot traffic is

expected either during or after the completion of

the roof.

Installation guidelinesHot-applied systems

The felt vapour control layer (VCL) in accordance with

BS 6229 should be fully sealed at all laps prior to

applying the insulation. At perimeters and abutments

the VCL should be turned up around the insulation

board edges and a flap of approximately 300mm

should be bonded to top surface of the insulation. The

VCL should be fully bonded to concrete decks using hot

bitumen adhesive, strip-bonded to the ribs of metal

decks and partially bonded to timber decks. On timber

decks, the VCL may be nailed to the deck but laps

should be sealed with the appropriate adhesive.

When used on metal decks Celotex EL3000 boards

should be laid with the perforated facer uppermost and

the long sides at right angles to corrugations and

bonded in a full mop of hot bitumen to the VCL. The

torch-on technique is not suitable with EL3000 and

should only be carried out on Celotex TC3000 boards.

Built-up flat roofing applications

T: 0901 996 0100* | celotex.co.uk | 29

Three layer felt system using torch-ontechnique

▶ The felt vapour control layer (VCL) in accordance

with BS 6229 should be fully bonded to the deck

prior to the installation of the insulation.

▶ Bond the boards to the VCL and lay the insulation

with joints break-bonded. Alternatively the boards

can be mechanically fixed to the deck.

▶ Loose lay the venting layer directly over the

insulation boards.

▶ Torch on the underlay sheet over the venting layer

and to finish torch the mineral surface cap sheet to

the underlay.

▶ To ensure the best possible bond, the torch-on

technique should apply 60% of the flame to the

board with 40% to the felt.

Celotex TC3000 is also compatible with pour and roll

and mastic asphalting installation techniques. Please

contact the Celotex Technical Centre for installation

guidance using these techniques.

Mechanical fastening

Guidance on fixings and patterns can be sought from

fixing manufacturers and in the BRUFMA information

document on mechanical fixings for rigid PIR roofboards.

Installation of weathering systems

Different types of weathering systems require different

installation instructions and guidelines. Advice on the

installation of these weathering systems should be

sought directly from the manufacturer or provider of

the weathering system type.

Laying pattern

It is recommended that the boards are laid with joints

break-bonded.

Supporting deck

The supporting deck must provide adequate supportfor the VCL and insulation board with joints beingsupported by the ridges of the deck. It must be capableof supporting the static and dynamic design loads andthe loads associated with the construction activitywithout deflection in excess of the limits defined in BS6399: Part 1. The deck must be structurally sound, dry,clean and where necessary primed before applicationof the weathering and insulating system.

TraffickingBoards are capable of withstanding the traffickingassociated with normal roof laying work. However, roofsare generally designed for occasional lightweight foottraffic or maintenance access. Where more frequent orheavier access is required, protective walkways shouldbe provided. Under no circumstances should the roofbe used as a working platform, either during or afterthe construction programme. Extra care should betaken to protect the insulation and weathering whenballasting.

Loose-laid roof boards under ballasted systemsWhen the ballasting system is not installed immediatelyfollowing the application of loose-laid roof boards,additional attachment is required. Please refer toBRUFMA Information Document "Securing PIR & PURRoof Boards Beneath Single-Ply WaterproofingMembranes" for further information.

Use of adhesivesWhen using adhesives, the installer should take carenot to use products that contain chemicals likely toattack the insulating foam such as ketonic solvents.Celotex EL3000 and Celotex TC3000 contains nochemicals or solvents likely to damage the PVCmembrane. When using adhesives, the installer shouldcheck the compatibility of the adhesive with theadhesive manufacturer.

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Single-ply membrane flat roofing applications

Construction Concrete Concrete Steel Steel Timber TimberDeck Deck Deck Deck Deck DeckFully Mechanically Fully Mechanically Fully Mechanically

Bonded Fixed Bonded Fixed Bonded FixedThickness Thickness Thickness Thickness Thickness Thicknes

(mm) (mm) (mm) (mm) (mm) (mm)

Outside surface resistance - - - - - -

Single-ply membrane 1.5 1.5 1.5 1.5 1.5 1.5

Variable layer See below See below See below See below See below See below

Polythene 1000 gauge, VCL - - - - - -

Concrete deck 250 250 n/a n/a n/a n/a

Steel deck n/a n/a 1.5 1.5 n/a n/a

Timber deck plywood n/a n/a n/a n/a 19 19

Cavity between joist at 11.7% bridging n/a n/a n/a n/a 150 150

Plasterboard n/a n/a n/a n/a 12.5 12.5

Inside surface resistance - - - - - -

Variable Layer

Celotex Thickness U-value U-value U-value U-value U-value U-valueProduct (mm) W/m2K W/m2K W/m2K W/m2K W/m2K W/m2K

Celotex EL3000 150 0.16 0.18 0.16 0.19 0.15 0.18

Celotex EL3000 140 0.17 0.19 0.17 0.20 0.16 0.19

Celotex EL3000 130 0.18 0.19 0.21 0.21 0.17 0.20

Celotex EL3000 120 0.20 0.22 0.20 0.23 0.19 0.21

Celotex EL3000 100 0.24 - 0.25 - 0.23 0.25

Example U-value calculation: EL3000 - single-ply membrane

Use Celotex EL3000 high performance insulation in

either mechanically fixed or fully adhered single-ply flat

roofing applications. The unperforated facer is suitable

for single-ply fully adhered roof systems and self-

adhesive membranes.

When designing a flat roof using Celotex EL3000

boards, three basic principles apply:

1. Design to a fall of 1:80, 1:60 or 1:40 as appropriate to

the weathering system, type of deck and



building and the need to ensure that the design will

not allow a build up of moisture below the


3. Provide adequate protection for both insulation and

waterproofing if significant foot traffic is expected

either during or after the completion of the roof.

Celotex EL3000with single-ply membrane

over metal deck

T: 0901 996 0100* | celotex.co.uk | 31

Installation guidelinesCold applied systems

For single-ply membranes, the VCL should be either

polythene or reinforced aluminium foil. The VCL should

be loose-laid immediately prior to installation of the

roof board and detailed at edges and abutments. The

VCL should be sealed and taped to the top surface of

the board.


The boards should be laid with all joints tightly butted

over the VCL and then mechanically secured through to

the deck. When used on metal decks, these roof boards

should be laid with the long edges at right angles to the

corrugations. When mechanical fasteners are utilised,

they should be selected to suit the type of deck used.

Celotex recommends the use of thermally broken fixings

with plate washers of a surface area of not less than

45cm². Fasteners should be installed between 50mm –

150mm from the edges and corners of the board.

The exact number of fixings required for each zone on a

flat roof must be calculated by the use of either BS 6399:

Part 2: 1997 Code of Practice for Wind Loads, or EN1991-1-4

used with the UK National Annex. A minimum of 6 fixings

per board must be used. Where more than 6 fixings per

board are required by the wind uplift calculation, the

higher figure must be adopted.

Guidance on fixings and patterns can be sought from



Installation of weathering systems

Different types of weathering systems require different

installation instructions and guidelines. Advice on the

installation of these weathering systems should be

sought from the manufacturer or provider of the

weathering system type.

Laying pattern

It is recommended that boards are laid with jointsbreak-bonded.

Supporting deck

The supporting deck must provide adequate support

for the VCL and insulation board with joints being

supported by the ridges of the deck. It must be capable

of supporting the static and dynamic design loads and

the loads associated with the construction activity

without deflection in excess of the limits defined in BS

6399:Part1. The deck must be structurally sound, dry,

clean and, where necessary, primed before application

of the weathering and insulating system.

Trafficking

Boards are capable of withstanding the trafficking

associated with normal roof laying work. However, roofs

are generally designed for only occasional lightweight

foot traffic or maintenance access. Where more frequent

or heavier access is required, protected walkways should

be provided. Under no circumstances should the roof be

used as a working platform, either during or after the

construction programme. Extra care should be taken to

protect the insulation and weathering when ballasting.

Loose-laid roof boards under ballasted systemsWhen the ballasting system is not installed immediatelyfollowing the application of loose-laid roof boards,additional attachment is required. Please refer toBRUFMA Information Document "Securing PIR & PURRoof Boards Beneath Single-Ply WaterproofingMembranes" for further information.

Use of adhesivesWhen using adhesives, the installer should take care notto use products that contain chemicals likely to attackthe insulating foam such as ketonic solvents. CelotexEL3000 contains no chemicals or solvents likely todamage the PVC membrane. When using adhesives, theinstaller should check the compatibility of the adhesivewith the adhesive manufacturer.

Liquid applied membranesIf liquid applied membrane systems are being consideredfor use with Celotex EL3000, advice on compatibility andapplication procedures should be sought directly fromthe manufacturer of the liquid applied system.

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Construction Concrete Concrete Steel Steel Timber Timber Deck Deck Deck Deck Deck Deck

Mechanically Thermally Mechanically Thermally Mechanically Thermally Fixed broken Fixed broken Fixed broken

Thickness Thickness Thickness Thickness Thickness Thickness(mm) (mm) (mm) (mm) (mm) (mm)

Outside surface resistance - - - - - - Single-ply membrane 1.5 1.5 1.5 1.5 1.5 1.5Variable layer See below See below See below See below See below See belowPolythene 1000 gauge, VCL - - - - - - Concrete deck 250 250 n/a n/a n/a n/aSteel deck n/a n/a 1.5 1.5 n/a n/aTimber deck plywood n/a n/a n/a n/a 19 19Cavity between joist @ 11.7% Bridging n/a n/a n/a n/a 150 150Plasterboard n/a n/a n/a n/a 12.5 12.5Inside surface resistance - - - - - -

Variable LayerCelotex Thickness U-value U-value U-value U-value U-value U-value Product (mm) W/m²K W/m²K W/m²K W/m²K W/m²K W/m²KTA4000 135 0.18 0.16 0.18 0.16 0.17 0.15TA4000 125 0.19 0.17 0.20 0.17 0.19 0.16TA4000 115 0.21 0.18 0.21 0.19 0.20 0.17TA4000 100 0.23 0.21 0.24 0.21 0.22 0.20TA4000 90 0.25 0.23 - 0.24 0.24 0.22TA4000 85 - 0.24 - 0.25 0.25 0.23

Example U-value calculation: TA4000 - single-ply membrane

Celotex TA4000 overconcrete deck

Use Celotex TA4000 high performance insulation in

mechanically fixed, single-ply flat roofing systems

where the higher compressive strength of the board

gives improved resistance to site traffic during

installation.

When designing a flat roof using Celotex TA4000

boards, three basic principles apply:

1. Design to a fall of 1:80, 1:60 or 1:40 as appropriate to

the weathering system, type of deck and



building and the need to ensure that the design will

not allow a build up of moisture below the


3. Provide adequate protection for both insulation and

waterproofing if significant foot traffic is expected

either during or after the completion of the roof.

Installation guidelinesLaying pattern

It is recommended that Celotex TA4000 boards are

laid with joints break-bonded. When used on metal

decks, the Celotex TA4000 boards should be laid with

the long sides at right angles to the corrugations.

Single-ply systems

Different types of weathering system require differentinstallation instructions and guidelines. Advice on theinstallation of these weathering systems should besought from the manufacturer or provider of theweathering system type.

Single-ply membrane flat roofing applications

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The boards should be laid with all joints tightly butted

over the VCL and then mechanically secured through to

the deck. When used on metal decks, these roof boards

should be laid with the long edges at right angles to the

corrugations. When mechanical fasteners are utilised, they

should be selected to suit the type of deck used. Celotex

recommends the use of thermally broken fixings with

plate washers of a surface area of not less than 45cm².

Fasteners should be installed between 50mm – 150mm

from the edges and corners of the board.

The exact number of fixings required for each zone on a

flat roof must be calculated by the use of either BS 6399:

Part 2: 1997 Code of Practice for Wind Loads, or EN1991-1-

4 used with the UK National Annex. A minimum of 6

fixings per board must be used. Where more than 6

fixings per board are required by the wind uplift

calculation, the higher figure must be adopted.

Further guidance on fixings and patterns can be sought from



Trafficking

Boards are capable of withstanding the trafficking

associated with normal roof-laying work. However, flat

roofs are generally only designed for occasional

lightweight foot traffic for maintenance access. Where

more frequent or heavier access is required, protected

walkways should be provided. Under no circumstances

should the roof be used as a working platform, either

during or after the construction programme. Extra care

should be taken to protect the insulation and

weathering when ballasting.

Loose-laid roof boards under ballastedsystems

When the ballasting system is not installed

immediately following the application of loose-laid

roof boards, additional attachment is required. Please

refer to BRUFMA Information Document "Securing PIR

& PUR Roof Boards Beneath Single-Ply Waterproofing

Membranes" for further information.

Vapour control layer (VCL)

The VCL should be minimum 1000 gauge polythene or

reinforced aluminium foil. This should be fully sealed at

all laps, prior to applying the insulation, using self-

adhesive tape appropriate to the type of VCL used.

At perimeters and abutments, the VCL should be turned

up around the insulation board edges and a flap of

approximately 300mm should be sealed and taped to

the top face of the board. The VCL should be loose laid

immediately prior to the installation of the roof

insulation board.

Upstands

Where an insulated upstand is needed, Celotex TB4000,

GA4000 and XR4000 are suitable to meet this requirement.

Supporting deck

The supporting deck must provide adequate support

for the VCL and insulation board, with joints supported

by the ridges of the deck. The deck must be structurally

sound, dry, clean and, where necessary, primed before

application of the weathering and insulating system.

Celotex TA4000 overmetal deck

Celotex TA4000 overtimber deck

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Flat roof insulating deck

Example U-value calculation: warm flat roof – insulating deck

Construction Celotex TD4000 - BUR Celotex TD4000 - SPMThickness (mm) Thickness (mm)

Outside surface resistance - - Built-up roofing or single-ply membrane 12 1.5 [see note]Plywood n/a 12

Variable layer See below See belowCavity between joist @ 400 Ctrs -11.7% 150 150Plasterboard 12.5 12.5Inside surface resistance - -

Variable Layer Thickness U-value U-value (mm) W/m²K W/m²K

Celotex TD4000 126 0.18 0.18Celotex TD4000 116 0.19 0.19Celotex TD4000 106 0.20 0.20Celotex TD4000 96 0.22 0.22

BUR = Built-up roofingSPM = Single-ply membraneNote: Prior to weatherproofing the roof, check with the single-ply membrane manufacturer that the proposed weatheringsystem is suitable for use with this type of construction.

Use Celotex TD4000 to combine high performance

thermal insulation with 5.5mm WBP ply for use in flat

roof deck applications to minimise insulation thickness


▶ Three-in-one product to provide deck, vapour

control layer (VCL) and insulation

▶ Provides reliable long term energy savings

for buildings

▶ Ideal for use in occasionally trafficked applications

▶ Warm roof construction due to over joist installation

▶ Rapidly installed and weatherproofed

▶ Accepts a wide variety of weathering systems

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▶ Ensure that joist spacing is at no more than 600mm

centres and that the dimension of the joist is

sufficient to span and accept additional loads. If

asphalt weathering is to be used, joists should be at

no more than 400mm centres.

▶ Install the insulation boards, ensuring that the long

edges are parallel to the line of the joists. 50mm x

50mm cross noggings should be inserted between

joists to support the short edges of the boards.

▶ Where boards butt together, bed onto twin beads of

vapour sealant wide enough to accommodate this

arrangement. This completes the vapour control

layer (VCL) when combined with each board’s foil

facings.

▶ Lay the boards with the plywood side uppermost

and stagger board joints. Leave a gap of

approximately 2mm between boards and ensure a

minimum 20mm bearing on joists and noggins.

▶ Fix Celotex TD4000 with corrosion-proof Suretwist

Composite Panel helical fasteners at a frequency to

suit the design wind load. Refer to BS 6399-2 Code

of Practice for Wind Loads. A minimum of 16

fasteners per board will resist a wind load of 2.22

KN/m2 based on a design load of 0.4KN per

fastener.

▶ Ensure that fixings are no less than 10mm in from

the board edge or 50mm from each corner. They

should be equally spaced along the supporting

joists. Fixings should be long enough to penetrate at

least 38mm into the supporting timber.

▶ Stagger opposing fixings where two board edges

share the same joist or noggin.

▶ Provide a complete insulation envelope by

extending the wall insulation board up to the

underside of the roof deck.

▶ Provide a soffit or ceiling below the joists, as the

surface of the product is not designed to be used

as a decorative internal finish.

▶ Ensure that the plywood is completely dry before

any weathering system is applied.

▶ Always use a Type 3G felt to BS 747 as a vapour

diffusion first layer when using BUR weathering

systems. When using a single-ply membrane,

additional 12mm plywood has to be applied on

top of the Celotex TD4000.

▶ Temporary protection must be provided for both

the insulation and the waterproofing, if significant

foot traffic is anticipated either during or after

installation.

FallsThe structure should be designed so that the finishedroof has a continuous, smooth and even slope towardsthe rainwater outlet or gutter. The minimum fallshould be 1:80 to avoid ponding water.

Deck stability

Celotex TD4000 incorporates exterior grade WBP

plywood to BS 1203, laminated to the surface. This gives

the product excellent strength. Boards can span up to

600mm joist centres to provide a suitable substrate for

a variety of weathering systems.

Vapour control layer

Celotex TD4000 has a built-in VCL due to the board’s foil

facer, but this is discontinuous at the board joints.

Therefore, a twin bead of vapour sealant should be

applied to the top of the supporting joists and noggins

at all board joints. This completes the VCL when

combined with each board’s foil facers.


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Example U-value calculation: cold flat roof - between and under joists

Construction

Outside surface resistanceWeatherproofing systemPlywoodVentilated cavityCelotex between joists @ 400 ctrs (11.7% brg)Variable layer (for below joists)Inside surface resistance

Variable Layer


GA = GA4000XR = XR4000

100mm 125mm 150mm 175mmdeep joists deep joists deep joists deep joists


- - - -n/a n/a n/a n/a19 19 19 1950 50 50 55

GA4050 GA4075 GA4100 XR4120 See below See below See below See below

- - - -


65 + 12.5 0.20 0.17 0.15 0.1460 + 12.5 - 0.18 0.16 0.1455 + 12.5 - 0.19 0.16 0.1550 + 12.5 - 0.20 0.17 0.1545 + 12.5 - - 0.18 0.1640 + 12.5 - - 0.19 0.1725 + 12.5 - - - 0.19

Insulation between and under joists

Use a combination of Celotex GA4000 or Celotex XR4000with Celotex PL4000 high performance plasterboard

thermal laminate in flat roof between and under joist

applications to minimise insulation thickness and give the

following benefits:

▶ Provides both the below joist insulation and

plasterboard in one product helping reduce

installation time

▶ Offers the installer maximum flexibility and installation

speed due to the tapered edge plasterboard

▶ A perfect solution to upgrade older buildings


for buildings

▶ No need to remove existing weatherproofing covering

▶ Ventilated cold roof construction

▶ The ideal renovation/conversion solution

▶ Helps to minimise any loss of internal headroom

T: 0901 996 0100* | celotex.co.uk | 37


▶ Make sure that there is enough joist depth to


insulation, but also a 50mm ventilated airspace

above the boards.

▶ Fix battens to the inside face of the joists so that the

bottom of the batten is 50mm below the decking.


face of the joists prior to cutting the board.

▶ The Celotex Insulation Clip is designed to allow

insulation boards to be installed between timber

joists quickly and without nails or screws.

▶ Fit the clips at one metre maximum centres along

the insulation (as described on page 15).

▶ Push the boards into the void between the joists

until they are tight up to the underside of stop

battens, ensuring that the lateral joints are tightly

butted.

▶ Secure Celotex PL4000 to the underside of the joists.

▶ Joints between the boards must be tightly butted,


jointing material to create the vapour control layer.

Composite systems can be used to combine Celotex

insulation under joist lining with quilt type insulant

between the joists which will provide acoustic, as well

as thermal insulation. This option is particularly useful

when upgrading to modern acoustic insulation

standards.

When updating an existing ceiling, Celotex PL4000

can be fitted directly underneath the ceiling,

providing there is no vapour check layer such as gloss

paint or foil backed plasterboard. Always ensure that

there is a 50mm minimum ventilation gap above any

original insulation.

Ventilation must be provided above an insulated ceiling

directly through the cold void. Failure to do so could

result in serious condensation problems that may lead

to decay and possible failure.

also suitable for this applicationTB4000

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Insulation solutions for walls

Travelodge | Maidstone

T: 0901 996 0100* | celotex.co.uk | 39

INCLUDING:

▶ Masonry cavity walls

▶ Internal solid masonry walls

▶ External solid masonry walls

▶ Timber frame walls

▶ Steel stud frame walls

▶ Rainscreen cladding

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Use Celotex CW4000 high performance thermal

insulation in partial fill cavity wall applications to

minimise insulation thickness and give the following

benefits:

▶ Easy to fit between wall ties using cavity tie

clips for retention


for buildings

▶ Low emissivity foil facers give improved

thermal insulation within cavity air spaces

▶ Excellent dimensional stability

▶ Conveniently sized boards for installation

between cavity wall ties

Fig. 1

Fig. 2

Fig. 3

Masonry cavity walls

T: 0901 996 0100* | celotex.co.uk | 41

▶ The wall ties used must be suitable for the structuralrequirements and incorporate a retaining clip toensure that the insulation is held permanently inplace. Normally the insulation is fitted against theinnner leaf of the wall.

▶ BBA-approved wall ties and clips should be usedwherever possible. The advice of the wall tiemanufacturers should be followed, but Celotex doesnot consider butterfly ties to be suitable for use withpartial-fill cavity insulation.

▶ The first row of board-retaining wall ties should beinstalled at least one course below the damp proofcourse (DPC) and positioned at maximum 600mmcentres horizontally, to provide a minimum supportof two ties per 1200mm board.

▶ The second and subsequent rows of ties should beinstalled at 450mm centres vertically and maximum900mm centres horizontally. Where required forstructural purposes, it may be necessary to install tiesat closer centres.

▶ Always ensure that each full or cut board is retainedby no fewer than three ties around its perimeter.

▶ Fit the boards between the wall ties, and secure inplace with a retaining clip on each tie. Ensure thathorizontal and vertical joints are tightly butted tominimise heat loss.

▶ At openings such as doors and windows, use aproprietary insulated cavity closer.

▶ Where necessary, cut the boards to size using theCelotex Insulation Saw and straight edge.

▶ Where the cavity is closed at or below DPC level by amethane barrier membrane, use mechanical fixingsto secure the board to the brickwork above the DPC.Avoid puncturing the gas barrier membrane.

▶ At internal (see Fig.2) and external (see Fig.3) angles,ensure that the thickness of the board continuesaround the angle and that sufficient wall ties are used.

Gable wallsAt gable walls (see Fig.4) it is recommended thatCelotex CW4000 is taken up to the underside of theroof verges. In cold roof constructions, the productshould extend at least 250mm above the ceilinginsulation. The top edge of the insulation should beprotected with a cavity tray.

Cavity fire barriers

Cavity barriers are not required in any walls that

comply with Approved Document B3 diagram 32, but

the cavity must be closed at the top and around any

openings.

Celotex CW4000, being a non-melting thermoset

material, may pass through cavity barriers so that a

thermal bridge is avoided.

Cavity obstructions

Unavoidable projections into the cavity, such as floor

edge beams and steel columns, need careful detailing

and may require a horizontal cavity tray.

To comply with the requirement of the National House

Building Council (NHBC) or Housing Association

Property Mutual (HAPM), a minimum 50mm clear

residual cavity should be provided in any exposed zone.

For buildings up to 12m high, a minimum clear cavity

width of 25mm may be acceptable, subject to exposure.

The 25mm minimum constructed residual cavity width

must be clear of all obstructions.


Fig. 4


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Blockwork comparison list

This table lists known lambda values

of major blockwork manufacturers’

products. Check with your supplier for

the latest information.

Thermal bridgingIn the past, buildings failed to achieve

their U-values. This was due to

thermal bridging that had not

previously been taken into account.

Mortar joints between insulating

concrete blocks are a significant

example, but timber in stud framing is

another less well known form.

LAMBDA explainedThis Greek symbol is used to

represent the Thermal

Conductivity of a material, measured

in Watts per metre Kelvin (W/mK). The

block values quoted are taken from

the manufacturers’ literature or by

direct consultation with their

technical departments. The lambda

value for the Celotex CW4000 range is

0.022 W/mK, as confirmed on the

product’s CE marked labels.

Reading the tableAll of the following recommendations

are based on a wall construction of

103mm brickwork, a 50mm clear

cavity, Celotex cavity wall insulation to

the thickness specified, a block inner

leaf thickness of 100mm, finished on

the inside with a lightweight plaster.

Simply select the type of block that

you wish to use and read across to the

minimum thickness of Celotex CW4000

needed for the desired U-value.

NB. Always install with the unprinted

foil surface facing the air cavity.

λ

Block Block Block U-Value (W/m2K)manufacturer name lambda λ 0.28 0.25 0.20

Armstrong Lightweight 0.42 CW4050 CW4060 CW4090Dense 1.13 CW4055 CW4065 CW4090

Besblock Insulite Solid 0.34 CW4050 CW4060 CW4085Celcon Solar 0.11 CW4040 CW4050 CW4075

Standard 0.15 CW4045 CW4055 CW4080Hi-Seven 0.19 CW4045 CW4055 CW4085

Forticrete Lightweight 0.42 - 0.59 CW4055 CW4060 CW4090Dense 0.93 - 1.13 CW4055 CW4065 CW4090

Hanson Ultralite 0.29 CW4050 CW4060 CW4085Superlite 0.40 CW4050 CW4060 CW4090Fenlite 0.48 CW4050 CW4060 CW4090Evalast 1.32 CW4055 CW4065 CW4090

Interfuse Optilyte 0.20 CW4045 CW4055 CW4085Interlyte 0.47 CW4050 CW4060 CW4090Intercrete 1.13 CW4055 CW4065 CW4090

Lignacite SP 0.79 CW4055 CW4065 CW4090Standard 0.90 CW4055 CW4065 CW4090

Masterblock Pumalite 0.44 CW4050 CW4060 CW4090Lightweight 0.59 CW4055 CW4060 CW4090Dense 1.06 CW4055 CW4065 CW4090

Mona Precast Fibotherm 0.25 CW4050 CW4060 CW4085Monalight 100S 0.50 CW4050 CW4060 CW4090Monacrete 100 0.59 CW4055 CW4060 CW4090GPI 0.41 CW4050 CW4060 CW4090Monacrete 100S 1.13 CW4055 CW4065 CW4090

Plasmor Fibolite 0.27 CW4050 CW4060 CW4085Aglite 0.32 CW4050 CW4060 CW4085Stranlite 0.46 CW4050 CW4060 CW4090Plascon 1.06 CW4055 CW4065 CW4090

RMC Readyblock 1100 0.34 CW4050 CW4060 CW4085Readyblock 1400 0.59 CW4055 CW4060 CW4090Readyblock Dense 1.13 CW4055 CW4065 CW4090

Stock Blocks Ultralite 0.25 CW4050 CW4060 CW4085Insulite 0.40 CW4050 CW4060 CW4090Lyta 0.56 CW4055 CW4060 CW4090Dense Concrete 0.99 - 1.25 CW4055 CW4065 CW4090

Thermalite Turbo 0.11 CW4040 CW4050 CW4075Shield 0.15 CW4045 CW4055 CW4080Hi-Strength 7 0.19 CW4045 CW4055 CW4085Hi-Strength 10 0.20 CW4045 CW4055 CW4085

Topblock Supabloc 0.11 CW4040 CW4050 CW4075Supabloc 4 0.16 CW4045 CW4055 CW4080Supabloc 7 0.19 CW4045 CW4055 CW4085Toplite GTI 0.11 CW4040 CW4050 CW4075Toplite Standard 0.15 CW4045 CW4055 CW4080Toplite 7 0.19 CW4045 CW4055 CW4085Topcrete Fair Face 0.99 CW4055 CW4065 CW4090Topcrete Dense 1.28 CW4055 CW4065 CW4090Hemelite 3-5 0.45 CW4050 CW4060 CW4090Hemelite 7 0.47 CW4050 CW4060 CW4090Hemelite 10 0.49 CW4050 CW4060 CW4090

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Construction 103mm brick or 100mm block | cavity | Celotex insulation | 103mm brick or 100mm block |internal finish

Internal finish Blue = Lightweight plaster Pink = Plasterboard on plaster dabsExample For a U-value of 0.20 W/m2K using a block outer leaf lambda value of 0.59 with block inner value

of 0.19. You will need Celotex CW4080 with lightweight plaster finish or Celotex CW4075 with plasterboard on dabs.

λ 0.77 1.13 0.59 0.19 0.15 0.110.77 55 50 55 50 55 50 45 45 45 40 40 40

1.13 55 50 55 50 55 50 45 45 45 40 40 40

0.59 55 50 55 50 50 50 45 45 45 40 40 40

0.19 45 45 45 40 45 45 40 40 40 40 40 40

0.15 45 40 45 40 45 40 40 40 40 40 40 25

0.11 40 40 40 40 40 40 40 40 40 25 25 25

Inner leaf

Out

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Brick Block

BrickBlock

Thickness of Celotex insulation for a U-value of 0.28 W/m2K



λ 0.77 1.13 0.59 0.19 0.15 0.110.77 65 60 65 60 60 60 55 55 55 50 50 45

1.13 65 60 65 60 60 60 55 55 55 50 50 45

0.59 60 60 60 60 60 60 55 50 50 50 50 45

0.19 55 55 55 55 55 50 50 45 45 45 40 40

0.15 55 50 55 50 50 50 45 45 45 40 40 40

0.11 50 45 50 45 50 45 40 40 40 40 40 40

Inner leaf

Out

er le

af

Brick Block

λ 0.77 1.13 0.59 0.19 0.15 0.110.77 80 75 80 75 75 75 65 65 65 60 60 60

1.13 80 75 80 75 75 75 65 65 65 60 60 60

0.59 75 75 75 75 75 75 65 65 65 60 60 55

0.19 65 65 65 65 65 65 60 55 55 55 55 50

0.15 65 60 65 60 65 60 55 55 55 50 50 50

0.11 60 60 60 60 60 55 55 50 50 50 45 45

Inner leaf

Out

er le

af

Brick Block


λ 0.77 1.13 0.59 0.19 0.15 0.110.77 90 90 90 90 90 85 85 80 80 75 75 70

1.13 90 90 90 90 90 85 85 80 80 75 75 70

0.59 90 85 90 85 90 85 80 75 75 75 70 65

0.19 85 80 85 80 80 75 70 65 65 65 60 60

0.15 80 75 80 75 75 75 65 65 65 60 60 55

0.11 75 70 75 70 70 65 60 60 60 55 55 55

Inner leaf

Out

er le

af

Brick Block

BrickBlock

BrickBlock

BrickBlock

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Masonry cavity walls and plasterboard laminate

Celotex offers an alternative solution for partial fill

cavity wall applications enabling traditional sized cavity

wall widths to be maintained.

Celotex CW4000 provides the partial fill cavity wall

solution utilising the product’s super low lambda value

of 0.022W/mK along with low emissivity aluminium foil

facers which provide enhanced thermal performance

within a cavity air space.

As a secondary insulation measure, Celotex’

plasterboard thermal laminate PL4000 can be installed

on the warm side of the inner leaf, providing additional

thermal performance and plasterboard as one product.

This combined solution minimises insulation thickness

and offers the following benefits:

▶ Products with a lambda value of 0.022W/mK

providing some of the thinnest insulation solutions

available today

▶ Allows for the traditional cavity space of 100mm to

be maintained without changing construction

methods and risking the loss of plot space

▶ Provides an alternative solution for meeting the

improved U-values required for Part L 2010

▶ CW4000 includes low emissivity foil facers giving

improved thermal insulation within cavity air spaces

▶ PL4000 provides insulation and plasterboard as one

product helping reduce installation time and

offering maximum flexibility to the installer

▶ PL4000 is suitable for both direct bonding (dot &

dab) and mechanical fixing installations

▶ Provides reliable long term energy savings for

buildings

Installation guidelinesPartial fill cavity wallsGuidelines for the installation of partial fill cavity wallinsulation can be found on page 40 and 41 of this Handy Guide.

Internal walls using PL4000Guidelines for the installation of Celotex PL4000plasterboard thermal laminate can be found on page 47of this Handy Guide.

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Construction 103mm brick or 100mm block | cavity | 50mm Celotex CW4000 | 103mm brick or 100mm block |Celotex PL4000

All U-values shown below assume 50mm CW4000 as the partial fill cavity wall solution with a brick outer leaf(lambda 0.77W/mK) and a 3mm plaster skim. Installing alternative thicknesses of CW4000 within the cavity wallwill have an impact on achieved U-value. This solution is also possible using Celotex PL4000 mechanically fixedusing battens. For further information and U-values, please visit our online U-value calculator or contact theCelotex Technical Centre.


Example U-value Calculation: Partial fill cavity wall with internal layer of Celotex PL4000

Block lambda (W/mK)

Variable Layer ThicknessCelotex PL4000 65 + 12.5Celotex PL4000 60 + 12.5Celotex PL4000 55 + 12.5Celotex PL4000 50 + 12.5Celotex PL4000 45 + 12.5Celotex PL4000 40 + 12.5Celotex PL4000 25 + 12.5

1.13U-value(W/m²K)

0.150.160.170.170.180.190.21

0.59U-value(W/m²K)

0.150.160.160.170.180.180.21

0.15U-value(W/m²K)

0.140.150.150.160.160.170.19

1.13U-value(W/m²K)

0.160.160.170.180.180.190.22

0.59U-value(W/m²K)

0.150.160.170.170.180.190.22

0.15U-value(W/m²K)

0.150.150.160.160.170.170.20

Dot & Dab Mechanically fixed direct to wall

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Solid masonry walls

Example U-value calculation: dry line wall

ConstructionOutside surface resistanceBrick/BlockVariable layerInside surface resistance

Variable Layer

Celotex PL4000 joints taped as VCLCelotex PL4000joints taped as VCL


Thickness (mm)-

See belowSee below

-103 215 100 215

Brick Brick Block BlockThickness U-value U-value U-value U-value

(mm) (W/m²K) (W/m²K) (W/m²K) (W/m²K)

65 + 12.5 0.29 0.28 0.29 0.28

60 + 12.5 - 0.30 - 0.30

Internal insulation solutionsUse Celotex PL4000 high performance thermal

insulation in solid masonry wall applications to


benefits:

▶ Provides both the insulation and plasterboard in

one product helping reduce installation time

▶ Offers the installer maximum flexibility and

installation speed due to the tapered edge

plasterboard

▶ Is suitable for both direct bonding (‘dot and dab’)

and mechanical fixing installation

▶ Reduces heat bridges formed by mortar joints

▶ Ideal where no cavity exists


buildings

▶ Provides a vapour control layer (VCL) when board

joints are taped and jointed

▶ Particularly suited to refurbishment projects

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Installation guidelinesInstallation guidelines for internal liningsystems using direct bonding

▶ Ensure that existing walls are permeable. Strip anygloss paint or vinyl wallpaper.

▶ Use the Celotex Insulation Saw to cut the 1200mm x2400mm Celotex PL4000 boards to fit the floor-to-ceiling height of the room.

▶ Ensure a continuous seal at skirting, ceiling level andat openings by applying a continuous band ofgypsum adhesive. Gypsum adhesive at perimeteredges can be replaced with thin timber battens.

▶ Apply further dabs of gypsum adhesive. This shouldbe in accordance with the adhesive manufacturer’sinstructions.

▶ Align sheets against the dabs and secure into correctposition.

▶ Once the dabs are set, it is recommended thatadditional secondary fixings be applied to theCelotex PL4000. Exact fixing details should be inaccordance with the recommendations of the fixingmanufacturer.

▶ Joints between the boards must be tightly butted,taped and jointed using appropriate tape and jointingmaterial to create the vapour control layer (VCL).

▶ Line window and door reveals with thinner CelotexTB4000 boards to reduce the risk of thermal bridging.Fix a batten around the edge of the opening andscribe the board to fit the reveal. Cut the dry lining tosuit and mechanically fix into the masonry revealusing proprietary fixings. Finish using an angle fillet atthe frame and an angle bead or scrim tape atexternal corners.

▶ Please note that to avoid the load being directlyapplied to the Celotex PL4000, suitable mechanicalfixings should be used for other internal fittings.Advice on suitable fixings should be sought directlyfrom the fixing manufacturer.

▶ Please note that where existing walls are subject to theingress of excessive moisture, it is recommended thatCelotex PL4000 should be installed using mechanicalfixings rather than a direct bonding technique.

Installation guidelines for internal liningsystems using mechanical fixings


▶ Use the Celotex Insulation Saw to cut the 1200mm x2400mm Celotex PL4000 boards to fit the floor-to-ceiling height of the room.

▶ Secure Celotex PL4000 with suitable mechanicalfixings. Fixing details should be in accordance withthe fixing manufacturer’s instructions.

▶ Joints between the boards must be tightly butted,taped and jointed using appropriate tape andjointing material to create the VCL.

▶ Line window and door reveals as for directbonding technique in adjacent column.

Installation guidelines for internal liningsystems using mechanical fixings to timberbattens


▶ Fix treated softwood timber battens to the masonry.They should be set out a maximum of 600mmvertical centres to coincide with the edges of theboards. As a minimum requirement, horizontalbattens should be used to support the top andbottom of the board edges.

▶ Galvanised clout nails or timber drywall screwsshould then be used to fix the boards to the battens.Specific advice on suitable fixings should be sourceddirectly from the fixings manufacturer.

▶ Joints between the boards should be tightly buttedand finished by taping and jointing using appropriatetape and jointing material to create the VCL.

Installation guidelines for internal liningsystems using mechanical fixings to metallining systems

▶ Celotex PL4000 boards can be fixed to a number ofproprietary metal frame lining systems. The systemshould be fixed in accordance with themanufacturer’s instructions.

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Construction

Outside surface resistanceSoftwood weatherboardingCavity (ventilated)Breather membraneVariable layerBrickworkPlaster, lightweightInside surface resistance

Variable Layer

Celotex XR4000Celotex XR4000Celotex XR4000Celotex XR4000Celotex XR4000Celotex XR4000Celotex XR4000Celotex GA4000 Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000

Thickness(mm)

-19--

See below21513-

Example U-value calculation: external insulation

Thickness(mm)20016515014013012011010095908580757065

U-value(W/m2K)

0.100.120.130.140.150.160.180.190.200.210.220.240.250.260.28


External insulation solutionsUse Celotex GA4000 and Celotex XR4000 high

performance thermal insulation in solid masonry wall

applications to minimise insulation thickness and give

the following benefits:

▶ Reduces heat bridges formed by mortar joints

▶ Ideal where no wall cavity exists


for buildings

▶ Particularly suited to refurbishment projects

▶ Saves internal room space

Solid masonry walls

T: 0901 996 0100* | celotex.co.uk | 49

▶ Prior to the installation of the Celotex insulation

boards, the substrate must be checked for

soundness.

▶ Large, uneven projections should be removed and

all holes filled and levelled. Loose material should be

cleaned off to leave a sound, dry surface.

▶ Downpipes should be temporarily removed and, if

necessary, relocated after completion of installation.

Lengthening of overflow pipes should be allowed

for, together with extensions to sills.

▶ Starter batten and drip (for render finish) should be

located at least one half brick above the damp proof

course and fixed directly to the substrate with plugs

and screws.

▶ The Celotex insulation should be fixed to the

substrate using proprietary fasteners, which are

driven into pre-drilled holes.

▶ All insulation board joints should be tightly butted

and end joints staggered.

▶ Fix a breather membrane over the insulation with

minimum 100mm laps.

▶ Apply preservative-treated timber battens vertically

over the face of the breather membrane and

insulation, secured back to the underlying masonry.

Render finish

Fix stainless steel expanded metal lathing to the

battens. Proprietary systems are available with

reinforcing ribs to allow for a full span of 600mm

between battens.

The render system should then be applied in

accordance with manufacturer’s guidelines.

Tile hanging

Tilting fillets should be applied at horizontal junctions

to suit the design requirements.

Fix tile battens to vertical battens to suit the tile gauge.

Hang tiles in accordance with manufacturer’s

instructions.

Other cladding

Timber or other lightweight cladding systems can be

fixed to the vertical battens.



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Use Celotex GA4000 and Celotex XR4000 high

performance thermal insulation in timber frame wall

lining applications to minimise insulation thickness


▶ Offers the thinnest solution available


for buildings


insulation within cavity air spaces

▶ Reduces thermal bridging through studs and

rails, when used in a two-layer system

▶ Provides cavity for services

Construction

Outside surface resistanceBrickCavityPlywoodVariable layerCavity (low emissivity) between studs (15% brg)Polythene 1000 gauge, VCLPlasterboardInside surface resistance

Variable Layer

Celotex XR4000 between 175 stud (15% brg)Celotex XR4000 between 150 stud (15% brg)Celotex XR4000 between 150 stud (15% brg)Celotex XR4000 between 125 stud (15% brg)Celotex XR4000 between 125 stud (15% brg)Celotex GA4000 between 125 stud (15% brg)

Thickness(mm)

-103509

See below5.0/10.0/15.0/20.0/25.0

-12.5

-

Example U-value calculation: timber frame wall lining

Thickness(mm)150140130120110100

U-value(W/m2K)

0.190.210.210.240.250.25


Timber frame wall lining

T: 0901 996 0100* | celotex.co.uk | 51

▶ Make sure all studs and rails are flush, with no

projections, and that services are correctly installed.

▶ Insert insulation into framing and push back to

plywood sheathing. Fit services into cavity if

required.

▶ Use the Celotex Insulation Saw to cut the boards to

fit tightly between all studs and rails.


foil surface should face the air cavit.y

▶ Use the Celotex Insulation Saw to cut the boards for

infill panels, using off-cuts where possible, making

sure there are no gaps at wall abutments.

▶ Ensure that the wall insulation is continuous with

the floor perimeter insulation.

▶ A vapour control layer (VCL) should be installed

over the warm side of the studwork.

▶ Fix plasterboard lining over the VCL using

plasterboard nails or screws.

NB: Some building insurance companies may

require additional third party approval when using

insulation in timber frame applications. Advice

should be sought from the relevant parties prior to

specifying the insulation required. Celotex insulation

is covered by BBA certificate number 09/4667.



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Single timber frame wall lining anddormer cheeks

Construction

Outside surface resistanceWeatherboard - Tiles - Rendered - Code 4 leadVentilated cavity batten air spaceBreather membranePlywoodCelotex between 100mm studs @ 400 ctrs (11.7% brg)Low E cavity between studs @ 400 ctrs (15% brg)Variable layer (for over studs)Inside surface resistance

Variable Layer


Weatherboarding Tile Hung Rendered Lead CladThickness Thickness Thickness Thickness

(mm) (mm) (mm) (mm)- - - -

any any 20 1.825 n/a n/a 25- - - -

12 12 12 12†GA4060 GA4060 GA4060 GA4060

40 40 40 40

See below See below See below See below- - - -


65 + 12.5 0.17 0.17 0.17 0.1760 + 12.5 0.18 0.18 0.18 0.1855 + 12.5 0.19 0.18 0.19 0.1950 + 12.5 0.19 0.19 0.19 0.2045 + 12.5 0.20 0.20 0.20 0.2140 + 12.5 0.21 0.21 0.21 0.2125 + 12.5 0.25 0.25 0.25 0.25

GA = Celotex GA4000Low E = Low emissivity† When using lead clad, the plywood layer is moved to outside the ventilated batten airspace

Example U-value calculation: single timber frame wall

Rendered

Celotex offers two solutions for single timber frame

wall lining applications. The first utilises the low lambda

values of Celotex GA4000 between the studs, followed

by an internal lining of Celotex PL4000 over the studs.

This solution gives the thinnest build-up with better

thermal insulation performance. The Celotex PL4000provides the over stud insulation and plasterboard in

one product, helping reduce installation time.

The second option is to use mineral wool batts fitted

between the studs, followed by an internal lining

of Celotex PL4000 over the studs. This solution

gives a thicker build-up but offers improved

acoustic insulation.


projections, and that services are correctly installed.

▶ Fit Celotex insulation or mineral wool batts tightly

in-between all studs and push up to plywood

sheathing.


foil surface should face the air cavity within the

studwork.

▶ Use the Celotex Insulation Saw to cut the boards for

infill panels, using off-cuts where possible, making

sure there are no air gaps at wall abutments.

▶ Install Celotex PL4000 insulation over the studs.

▶ Tightly butt edges of boards together, making sure

there are no gaps and fix back to solid timber, both

at stud lines and at top and bottom rails.

▶ Joints between the boards must be tightly butted,


jointing material to create the vapour control layer

(VCL).

▶ Vapour seal all perimeter abutments using sealant.

▶ Seal around all penetrations for electrical outlets

and switch boxes.





specifying the insulation required. Celotex insulation

is covered by BBA certificate number 09/4667.


Lead clad

Tile hung

Weatherboarding

also suitable for this applicationTB4000

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54 | T: 0901 996 0100* | celotex.co.uk

Use Celotex GA4000 high performance insulation in

timber frame wall sheathing applications to minimise

insulation thickness and give the following benefits:

▶ Eliminates thermal bridging of timber


for buildings

▶ Low emissivity foil facers give improved

thermal insulation performance within cavity

air spaces

▶ Sheathing encapsulates the timber frame

▶ No threat of interstitial condensation

▶ Voids between studs free for services

Construction

Outside surface resistanceBrickCavity (low emissivity)Variable layerPlywoodCavity between studsPolythene 1000 gauge, VCLPlasterboardInside surface resistance

Variable Layer

Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000 Celotex GA4000Celotex GA4000Celotex GA4000 Celotex GA4000

Thickness(mm)

-10350

See below9

89-

12.5-

Example U-value calculation: timber frame wall sheathing

Thickness(mm)10095908580757065605550

U-value(W/m2K)

0.180.180.190.200.210.210.220.230.250.260.28


Timber frame wall sheathing

T: 0901 996 0100* | celotex.co.uk | 55


projections.

▶ Fix sheet of Celotex GA4000 to the external

sheathing using galvanised clout nails at 400mm

centres in the centre of the board and at 300mm

centres around the perimeter.


foil surface should face the air cavity.

▶ Care must be taken to align the fixings with

underlying studs, sole plates and head rails.

▶ Tightly butt boards together and use off-cuts to fill

in around waist rails.

▶ Brickwork should be tied back to the timber

framing using helical stainless steel wall ties, driven

through the Celotex insulation into the studs.

▶ Insert ties approximately 10mm to 20mm above the

brick course so that a slight ‘crank’ can be applied.

This ensures that the tie slopes downward from the

sheathing to the outer brickwork.

▶ Install horizontal cavity barriers, usually in the form

of mineral wool ‘sausages’, to the surface of the

Celotex insulation board at all intermediate floors.

▶ Apply vertical and horizontal cavity barriers in a

similar fashion around window and door openings.





specifying the insulation required. Celotex

insulation is covered by BBA certificate number

09/4667.

Gable walls

At gable walls, it is recommended that the insulation be

taken up to the underside of the roof verges. However,

if a cold roof construction is intended, the cavity

insulation should extend at least 250mm above the

ceiling. The top edge of the insulation should be

protected with a cavity tray.

Other cladding

Tile hanging, render finish, weather boarding and other

cladding types are all suitable for this application. In

this situation, Celotex boards can be protected with a

breather membrane. However, advice and information

on the installation of these cladding systems should

be sought from the manufacturer or provider of the

cladding system.



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Use Celotex TB4000 or Celotex GA4000 high

performance thermal insulation in steel stud framed

wall applications to minimise insulation thickness and

give the following benefits:

▶ Ideal for lightweight, steel framed commercial andindustrial buildings


▶ Low emissivity foil facer gives improved thermalinsulation performance within cavity air spaces

▶ Rapid, accurate construction on-site

▶ Facilitates off-site fabrication of framed panels

▶ Warm frame construction eliminates thermalbridging through studs

▶ Thin overall construction depth

Construction

Outside surface resistanceBrickCavity (low emissivity)Variable layer (over studs)Cavity (low emissivity)Polythene 1000 gauge, VCLPlasterboardPlasterboardInside surface resistance

Variable Layer

Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex GA4000Celotex TB4000Celotex TB4000Celotex TB4000Celotex TB4000

Thickness(mm)

-10350

See below100

-12.512.5

-

Example U-value calculation: steel stud framed wall

Thickness(mm)1009590858075706560555045403530

U-value(W/m2K)

0.170.180.190.190.200.210.220.230.240.250.270.280.300.310.34


Steel stud framed walls

T: 0901 996 0100* | celotex.co.uk | 57

▶ Install the steel stud framework in accordance with

the manufacturer’s instructions.


foil surface should face the air cavity.

▶ If necessary, trim the Celotex insulation boards to a

width and height to ensure that the edges are fully

supported by the frame studs or horizontal runners.

▶ Trim boards to fit around window and door

openings.

▶ Place the boards directly against the external face of

the steel frame and temporarily fix with suitable

self-tapping screws and washers.

▶ Adjacent boards must be tightly butted to minimise

heat loss.

▶ Where the frame is to be faced with brickwork, place

wall tie retaining channels over the boards at stud

positions and fix through the insulation into the

studs with fasteners as recommended by the

channel manufacturer.

▶ Construct the brickwork facing incorporating

twist-in ties at recommended intervals.

▶ Fit cavity barriers between the brickwork and the

face of the insulation board as required.

Other cladding

Tile hanging, render finish, weather boarding and other

cladding types are all suitable for this application. In this

situation, Celotex boards must always be protected

with a breather membrane. However, advice and

information on the installation of these cladding

systems should be sought from the manufacturer or

provider of the cladding system.



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Use Celotex TB4000 or Celotex GA4000 high

performance thermal insulation in rainscreen cladding

applications up to 18 metres in height to minimise

insulation thickness and give the following benefits:

▶ Ideal for use with masonry, steel or timber frame

systems


buildings


insulation values with cavity air spaces

▶ Suitable for use with many cladding type products

▶ Warm frame construction elimates thermal

bridging through studs

Construction With rails or brackets With rails or bracketsbridging insulation over insulation

Thickness (mm) Thickness (mm)Outside surface resistance - - Cladding - -Ventilated cavity between rails/brackets - -Breather membrane - -Variable layer See below See belowLow E cavity between steel frame 100 100Polythene 1000 gauge, VCL & airleakage barrier - -Plasterboard 12.5 12.5Plasterboard 12.5 12.5Inside surface resistance - -

Variable Layer Thickness U-value U-value (mm) W/m²K W/m²K

Celotex GA4000 100 0.26 0.20Celotex GA4000 95 0.26 0.20Celotex GA4000 90 0.27 0.21Celotex GA4000 85 0.28 0.22Celotex GA4000 80 0.29 0.23Celotex GA4000 75 0.30 0.25Celotex GA4000 70 0.32 0.26Celotex GA4000 65 0.33 0.27Celotex GA4000 60 0.35 0.29Celotex GA4000 55 - 0.31Celotex GA4000 50 - 0.33Celotex TB4000 45 - 0.35

Low E = Low emissivity

VCL = Vapour control layer

Rainscreen cladding

Example U-value calculation: rainscreen cladding (up to 18 metres)

T: 0901 996 0100* | celotex.co.uk | 59

▶ Please note that Celotex GA4000 can only be used

in rainscreen cladding applications up to 18metres

in height.

▶ Tile hanging, weather boarding and other cladding

types are all suitable for this application. Celotex

boards must always be protected with a breather

membrane.

▶ In all instances, advice and information on the

installation and fixings of cladding systems should

be sought directly from the manufacturer or

provider of the cladding system.


foil surface of the insulation should face the air

cavity between the steel frame.

▶ When cutting Celotex insulation boards on site, use

the Celotex Insulation Saw.



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Insulation solutions for floors

Punch Taverns | Staffordshire

T: 0901 996 0100* | celotex.co.uk | 61

INCLUDING:

▶ Concrete slab floors

▶ Beam and block floors

▶ Suspended timber floors

▶Underfloor heating

▶ Concrete soffit floors

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Calculating the P/A ratio

U-value calculationsTo calculate the minimum thickness of insulation needed in a

floor you should divide the exposed internal perimeter by

the internal area which will give you the P/A ratio.

Example 1 – detached dwelling

The overall internal dimensions of the dwelling are 8.10m x

6.90m; these measurements ignore the internal walls.

The exposed perimeter is 8.10m + 6.90m +

8.10m + 6.90m = 30.0m

The area is 8.10m x 6.90m = 55.89m

The P/A ratio is 30 / 55.89 = 0.54

For this example, with a concrete slab floor,

you will require:

65mm of insulation to achieve 0.22 W/m2K




Example 2 – new extension

The overall internal dimensions of the dwelling are 3.10m x

2.40m; these measurements ignore the internal walls.

The exposed perimeter is 2.40m + 3.10m + 1.22m = 6.72m

The area is 3.10m x 2.40m = 7.44m

The P/A ratio is 6.72 / 7.44 = 0.90


you will require:





T: 0901 996 0100* | celotex.co.uk | 63

Example 3 – dwelling with integral garage

The overall internal dimensions of the dwelling are

8.50m x 6.90m; these measurements ignore the internal

walls.

The exposed perimeter is 8.50m + 6.90m + 7.30m +

2.88m + 1.20m + 4.02m = 30.8m

The area is (8.50m x 6.90m) – (1.20m x 2.88m) = 55.19m

The P/A ratio is 30.8 / 55.19 = 0.55


you will require:





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U-value ready reckoner: ground floor – concrete slab

0.12

0.12

0.12

0.11

0.11

0.11

0.11

0.10

0.10

0.10

0.10

0.09

0.09

0.09

0.08

0.08

0.08

0.07

0.07

0.18

0.17

0.17

0.16

0.15

0.15

0.14

0.14

0.13

0.13

0.13

0.12

0.11

0.11

0.11

0.10

0.09

0.09

0.08

0.22

0.21

0.20

0.19

0.18

0.17

0.16

0.16

0.15

0.15

0.14

0.13

0.13

0.12

0.12

0.11

0.11

0.10

0.09

0.24

0.22

0.21

0.20

0.19

0.18

0.18

0.17

0.16

0.16

0.15

0.14

0.13

0.13

0.13

0.12

0.11

0.11

0.09

0.25

0.24

0.23

0.21

0.20

0.20

0.19

0.18

0.17

0.17

0.16

0.15

0.14

0.14

0.13

0.12

0.12

0.11

0.09

-

0.25

0.24

0.22

0.21

0.20

0.19

0.19

0.18

0.17

0.17

0.15

0.14

0.14

0.14

0.13

0.12

0.11

0.09

-

-

0.24

0.23

0.22

0.21

0.20

0.19

0.18

0.18

0.17

0.16

0.15

0.14

0.14

0.13

0.12

0.11

0.10

-

-

0.25

0.24

0.23

0.21

0.20

0.20

0.19

0.18

0.17

0.16

0.15

0.14

0.14

0.13

0.12

0.11

0.10

-

-

-

0.24

0.23

0.22

0.21

0.20

0.19

0.18

0.17

0.16

0.15

0.15

0.14

0.13

0.13

0.12

0.10

-

-

-

0.25

0.23

0.22

0.21

0.20

0.19

0.18

0.18

0.16

0.15

0.15

0.14

0.13

0.13

0.12

0.10

Perimeter / Area ratio

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Based on 65mm screed & 20mm insulation as perimeter upstand

Celotex Product

GA4050 / FF4050

GA4055

GA4060

GA4065

GA4070 / FF4070

GA4075 / FF4075

GA4080

GA4085/FF4085

GA4090 / FF4090

GA4095

GA4100 / FF4100

XR4110

XR4120

FF4125

XR4130

XR4140

XR4150

XR4165

XR4200

Use Celotex GA4000, Celotex XR4000 or CelotexFF4000 high performance thermal insulation in

concrete slab floor applications to minimise insulation

thickness and give the following benefits:

▶ Easy to cut boards to fit in most spaces


for buildings


▶ No thermal bridging at floor edges

▶ Tightly butted joints for insulation continuity

Concrete slab floors

T: 0901 996 0100* | celotex.co.uk | 65

Over slab installation guidelines

▶ Install a damp proof membrane over the top of, or

below the slab. The damp proof membrane must

provide continuity with the damp proof course in

the surrounding walls.

▶ Level the surface of the slab; it should be smooth

and free of projections.

▶ If required, use a thin layer of sand blinding on a

rough, tamped slab to ensure that the insulation

boards are continuously supported.

▶ Use the Celotex Insulation Saw to cut and fit

insulation upstand to floor perimeter, to meet a

minimum R-value of 0.75m²K/W. i.e. Celotex TB4020.

The upstand depth should be equal to the sum of

the slab insulation and the screed thickness. The

upstand thickness should not exceed the combined

thickness of the wall plaster and the skirting.

▶ Lay the insulation boards directly onto the prepared

slab with all joints tightly butted.

▶ Lay a polythene vapour control layer (VCL) over the

insulation to minimise the risk of condensation

forming at the insulation/slab interface and to

prevent liquid screed migration.

▶ Apply a sand/cement or self levelling screed over

the VCL and Celotex insulation boards to a

minimum thickness of 65mm.

Use scaffold boards or other protection to preventwheelbarrows and other traffic damaging theinsulation.

These recommendations are suitable for normaldomestic floor loadings. If higher loadings are required,it may be necessary to increase the screed thicknessand provide reinforcement within the screed. Consult astructural engineer or a specialist flooring contractor.

Under slab installation guidelines

▶ Level hardcore and blind with sand.

▶ Install damp proof membrane and lap into damp

proof course.


insulation, thickness to achieve required U-value.


insulation upstand to floor perimeter, to meet a

minimum R-value of 0.75m²K/W. i.e. Celotex TB4020.

Height of insulation to coincide with required

finished floor level.



forming at the insulation/slab interface.

▶ Lay concrete to required finished floor level and

smooth over with float finish.

Chipboard floor finish

A VCL should be laid over the Celotex insulation

boards and turned up 100mm at room perimeters,

behind the skirting. It is recommended good practice

that all joints should be lapped 150mm and sealed.

The chipboard must be minimum 18mm tongued

and grooved flooring grade type C4 to BS 5669. Lay

the chipboard with staggered joints, glued with a

woodworking adhesive.

Provide a 10mm – 12mm gap at all perimeters and

abutments to allow for expansion. This can be

achieved by the use of temporary wedges.

Where chipboard is butted together without a tongued

and grooved joint and all external doorways (for the

width of the threshold), a treated timber batten must

be used in lieu of the insulation boards.



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U-value ready reckoner: ground floor – beam & block


0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Based on 65mm screed & 20mm insulation as perimeter upstand

Celotex Product

GA4050 / FF4050

GA4055

GA4060

GA4065

GA4070 / FF4070

GA4075 / FF4075

GA4080

GA4085 / FF4085

GA4090 / FF4090

GA4095

GA4100 / FF4100

XR4110

XR4120

FF4125

XR4130

XR4140

XR4150

XR4165

XR4200

Use Celotex GA4000, Celotex XR4000 or CelotexFF4000 high performance thermal insulation in beam

and block floors to minimise insulation thickness and

give the following benefits:


▶ Provide reliable long term energy savings for

buildings


▶ Optimised continuity with wall insulation

▶ Tightly butted joints for insulation continuity

Beam and block floors

0.16

0.16

0.15

0.15

0.14

0.14

0.13

0.13

0.13

0.12

0.12

0.11

0.11

0.11

0.10

0.10

0.09

0.09

0.08

0.22

0.21

0.20

0.19

0.18

0.17

0.17

0.16

0.16

0.15

0.14

0.14

0.13

0.12

0.12

0.11

0.11

0.10

0.09

0.24

0.23

0.22

0.21

0.20

0.19

0.18

0.18

0.17

0.16

0.16

0.15

0.14

0.13

0.13

0.12

0.12

0.11

0.09

-

0.25

0.23

0.22

0.21

0.20

0.19

0.18

0.18

0.17

0.16

0.15

0.14

0.14

0.13

0.13

0.12

0.11

0.09

-

-

0.24

0.23

0.22

0.21

0.20

0.19

0.18

0.18

0.17

0.16

0.15

0.14

0.14

0.13

0.12

0.11

0.10

-

-

0.25

0.24

0.22

0.21

0.20

0.19

0.12

0.18

0.17

0.16

0.15

0.14

0.14

0.13

0.12

0.11

0.10

-

-

0.25

0.24

0.23

0.22

0.21

0.20

0.19

0.18

0.17

0.16

0.15

0.15

0.14

0.13

0.12

0.11

0.10

-

-

-

0.24

0.23

0.22

0.21

0.20

0.18

0.18

0.18

0.16

0.15

0.15

0.14

0.13

0.13

0.12

0.10

-

-

-

0.25

0.23

0.22

0.21

0.20

0.19

0.19

0.18

0.16

0.15

0.15

0.14

0.13

0.13

0.12

0.10

-

-

-

0.25

0.24

0.22

0.21

0.20

0.19

0.19

0.18

0.17

0.15

0.15

0.14

0.14

0.13

0.12

0.10

T: 0901 996 0100* | celotex.co.uk | 67

▶ If appropriate, install a damp proof membrane to

the top surface of the beam and block floor.

▶ Level the surface of the floor; it should be smooth

and free of projections. Use a thin layer of sand

blinding to ensure that the insulation boards are

continuously supported.

▶ Use Celotex TB4020 boards as upstands to fit

around floor perimeters to eliminate thermal

bridging at screed edges. The upstand depth should

be equal to the screed thickness. The upstand

thickness should not exceed the combined

thickness of the wall plaster and the skirting.

▶ Lay the insulation boards directly onto the prepared

beam and block floor with all joints tightly butted.



forming at the insulation/slab interface and to

prevent liquid screed migration.

▶ Apply a sand/cement or self levelling screed over

the Celotex insulation boards to a minimum

thickness of 65mm.

Use scaffold boards or other protection to prevent

wheelbarrows and other traffic damaging the

insulation.

Chipboard floor finish

A VCL should be laid over the Celotex insulation boards

and turned up 100mm at room perimeters, behind the

skirting. It is recommended good practice that all joints

should be lapped 150mm and sealed.

The chipboard must be minimum 18mm tongued and

grooved flooring grade type C4 to BS 5669. Lay the

chipboard with staggered joints, glued with a

woodworking adhesive.

Provide a 10mm – 12mm gap at all perimeters and

abutments to allow for expansion. This can be achieved

by the use of temporary wedges.

Where chipboard is butted together without a tongued

and grooved joint and all external doorways (for the

width of the threshold), a treated timber batten must

be used in lieu of the insulation boards.



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68 | T: 0901 996 0100* | celotex.co.uk

Use Celotex GA4000 or Celotex XR4000 high

performance thermal insulation in suspended timber

floors to minimise insulation thickness and give the

following benefits:

▶ Quick and easy to install insulation between

joists in one layer

▶ Boards permanently retained by Celotex

insulation clip

▶ Minimise air leakage by friction fitting the insulation


buildings


insulation performance within air spaces

▶ Minimal load added to structure due to

light-weight boards

U-value ready reckoner: ground floor – suspended timber

0.18

0.18

0.17

0.17

0.16

0.16

0.16

0.15

0.15

0.15

0.14

0.14

0.13

0.13

0.12

0.12

0.11

0.10

0.25

0.24

0.23

0.22

0.22

0.21

0.20

0.20

0.19

0.19

0.18

0.17

0.16

0.16

0.15

0.14

0.13

0.12

-

-

-

0.25

0.24

0.24

0.23

0.22

0.21

0.21

0.20

0.19

0.18

0.17

0.16

0.15

0.14

0.13

-

-

-

-

-

0.25

0.24

0.24

0.23

0.22

0.21

0.20

0.19

0.18

0.17

0.16

0.15

0.13

-

-

-

-

-

-

0.25

0.25

0.24

0.23

0.22

0.21

0.19

0.18

0.17

0.17

0.15

0.13

-

-

-

-

-

-

-

0.25

0.24

0.24

0.23

0.21

0.20

0.19

0.18

0.17

0.16

0.14

-

-

-

-

-

-

-

-

0.25

0.24

0.23

0.22

0.20

0.19

0.18

0.17

0.16

0.14

-

-

-

-

-

-

-

-

0.25

0.24

0.23

0.22

0.21

0.19

0.18

0.17

0.16

0.14

-

-

-

-

-

-

-

-

0.25

0.25

0.24

0.22

0.21

0.20

0.18

0.17

0.16

0.14

-

-

-

-

-

-

-

-

-

0.25

0.24

0.22

0.21

0.20

0.19

0.18

0.16

0.14

Based on timbers joists @ 400 Ctrs

Celotex

Product

GA4050

GA4055

GA4060

GA4065

GA4070

GA4075

GA4080

GA4085

GA4090

GA4095

GA4100

XR4110

XR4120

XR4130

XR4140

XR4150

XR4165

XR4200

Suspended timber floors

Perimeter / Area ratio0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

T: 0901 996 0100* | celotex.co.uk | 69

▶ Install joists in the conventional manner, with solid

or diagonal strut bracing as necessary. (NB: diagonal

bracing may lead to thermal bridging).

▶ The Celotex Insulation Clip is designed to allow

insulation boards to be installed between timber

joists quickly and without nails or screws.

▶ Either fit the clips at one metre maximum centres

along the edge of the insulation (as described on

page 15) or fix battens to the sides of the joists to

support the insulation.

▶ Use the Celotex Insulation Saw to cut the boards

to achieve a tight fit, then push the boards firmly

down between the joists. The insulation clip will

ensure a friction fit.

▶ Insulate gaps between the joists and walls to

prevent thermal bridging.

▶ Install either chipboard or softwood floor boarding

directly onto the joists.

▶ Ensure that the void below the insulation is

ventilated.

Exposed floors (other than ground)

▶ For exposed or semi-exposed floors, e.g. garage or

car port ceilings, it may be easier to insulate from

below.

▶ Fix Celotex insulation boards directly to the

underside of the joists with galvanised clout nails at

400mm maximum centres. Finish with an

appropriate fire protection board fixed to the soffit.

▶ An additional layer of 100mm mineral wool

insulation can be installed between the joists,

supported by the soffit lining, to provide acoustic

insulation.



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70 | T: 0901 996 0100* | celotex.co.uk

Use Celotex FF4000 high performance thermal

insulation with underfloor heating applications to


benefits:

▶ Minimal downward heat loss into the structure


▶ Pipe retaining clips may be inserted directly into

the Celotex insulation


building structures


U-value ready reckoner: Celotex FF4000 for use with underfloor heating

CelotexProduct

FF4050FF4070FF4075FF4085FF4090FF4100FF4125

FF4050FF4070FF4075FF4085FF4090FF4100FF4125

FF4050FF4070FF4075FF4085FF4090FF4100FF4125

0.120.110.110.100.100.100.09

0.160.140.140.130.130.120.11

0.180.160.160.150.150.140.13

0.180.150.150.140.130.130.11

0.220.180.170.160.160.140.12

0.250.220.210.200.190.180.16

0.220.180.170.160.150.140.12

0.240.200.190.180.170.160.13

-0.240.240.220.210.200.17

0.240.190.180.170.160.150.13

-0.210.200.180.180.160.14

--

0.250.230.230.210.18

0.250.200.200.180.170.160.14

-0.220.210.190.180.170.14

---

0.240.240.220.19

-0.210.200.190.180.170.14

-0.220.210.190.190.170.14

---

0.250.240.230.19

-0.220.210.190.180.170.14

-0.230.220.200.190.170.15

----

0.250.230.20

-0.230.210.200.190.170.14

-0.230.220.200.190.180.15

----

0.250.230.20

-0.230.220.200.190.170.15

-0.230.220.200.190.180.15

----

0.250.240.20

-0.230.220.200.190.180.15

-0.240.220.200.190.180.15

-----

0.240.20


0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Susp

end

ed T

imb

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on

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dUnderfloor heating

T: 0901 996 0100* | celotex.co.uk | 71

Installation guidelinesPre-installation guidelines for concrete slabfloor applications only

▶ Install a damp proof membrane (DPM) below the

slab or apply a liquid waterproofing membrane to

the top surface of the slab.

▶ The DPM must provide continuity with the damp

proof course in the surrounding walls.

▶ Level the surface of the slab; it should be smooth and

free of projections.

▶ Use a thin layer of sand blinding on a rough, tamped

slab to ensure that the insulation boards are

continuously supported.

Use scaffold boards or other protection to preventwheelbarrows and other traffic damaging the insulation.

Installation guidelines for concrete slab andbeam & block floor applications

▶ Use Celotex TB4000 boards as upstands to fit around

floor perimeters to eliminate thermal bridging at screed

edges. The upstand depth should be equal to the sum

of the slab insulation and the screed thickness. The

upstand thickness should not exceed the combined

thicknesses of the wall plaster and the skirting.

▶ Lay the insulation boards directly into the prepared

slab/beam and block with all joints tightly butted.

▶ Install a polythene membrane over the insulation.

▶ Lay a proprietary underfloor heating system, generally

comprising pipework in coils. Pipe retaining clips may

be inserted directly into the Celotex insulation.

▶ Apply the screed over the Celotex insulation boards

to a thickness recommended by the manufacturer of

the underfloor heating system (normally 75mm).

▶ Compact the screed solidly when laid.

▶ Allow the screed to dry thoroughly before an

impermeable surface, such as a vinyl floor finish, is

applied. (Consult a specialist flooring contractor.)

These recommendations are suitable for normaldomestic floor loadings. If higher loadings are required itmay be necessary to increase the screed thickness andprovide reinforcement within the screed. Consult astructural engineer or specialist flooring contractor.

Installation guidelines for suspended timberfloor applications

▶ Install joists in the conventional manner, with solid or

diagonal strut bracing as necessary. (NB: diagonal

bracing may lead to thermal

bridging).

▶ Fix battens to the sides of the

joists to support the

insulation and to

form a cavity for

the underfloor

heating, between

the insulation

and floor boards.

▶ Use the Celotex

Insulation Saw to cut the

Celotex FF4000 insulation to

achieve a tight fit, then

push the boards firmly

down between the

joists.

▶ Insulate the gaps

between the

joists and wall

to prevent

thermal bridging.

▶ Lay a proprietary underfloor heating system within

the cavity, generally comprising pipework in coils, to

the manufacturer’s guidelines.

▶ Install either chipboard or soft wood floor

boarding directly onto the joists.

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72 | T: 0901 996 0100* | celotex.co.uk

Example U-value calculation: concrete soffit floors

Construction Thickness (mm)Outside surface resistance - Variable layer (mechanically fixed) See belowConcrete 150Inside surface resistance -

Variable Layer Thickness U-value (W/m²K) U-value (W/m²K)(mm) Mechanically Fixed Thermally Broken

Celotex SL4000 126 0.19 0.17Celotex SL4000 116 0.21 0.19Celotex SL4000 106 0.22 0.21Celotex SL4000 96 0.25 0.23Celotex SL4000 86 0.27 0.25Celotex SL4000 76 0.30 0.29Celotex SL4000 66 0.35 0.33Celotex SL4000 56 0.41 0.39U-value: For U-values see variable layer list.

Concrete soffit floors

Use Celotex SL4000 high performance thermal

insulation in concrete soffit floor applications to


benefits:

▶ Utilises the unrivalled insulation properties of

premium Celotex FR4000 with calcium silicate

providing additional fire performance

▶ Reduces installation times due to the insulation and

calcium silicate being supplied as one product

▶ Delivers greater impact resistance compared to

exposed insulation systems

▶ Provides a decorative finish with no need for on-site

decoration

▶ Is a lighter weight solution than other insulation

options

▶ Offers enhanced thermal performance and even

lower U-values

▶ Provides long term energy savings for buildings

T: 0901 996 0100* | celotex.co.uk | 73

▶ Prior to installation, the concrete soffit should be

checked to ensure that it is structurally sound, dry,

clean and where necessary primed before

application of the insulation board.

▶ It is recommended that SL4000 is installed with

joints tightly butted and break-bonded.

▶ SL4000 should always be installed directly to the

concrete soffit via mechanical fixings.

▶ Fixings should be evenly laid out with a minimum of

12 fixings per 1200mm x 2400mm board.

▶ Fixings should be installed between 50mm –

100mm from the edge and corners of the board.

Suitable fixings should comprise a screw type

suitable for both the product and concrete deck

into which it is being driven, combined with a

circular or rectangular plate washer having a surface

area of not less than 45cm². Advice on suitable

fixings should be sought directly from the fixing

manufacturer.


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Garage conversions

Upgrading existing floors: U-valuerequirement is 0.25 W/m²KWhen insulating floors, either with 65mm screed and

Celotex TB4020 edge insulation, or with an 18mm

chipboard finish, a 1200 gauge damp proof membrane

(DPM) must be laid below the Celotex. A minimum 500

gauge polythene layer must also be installed on top of

the insulation to prevent screed migration and any

reaction between the aluminium facer and the screed.

All floors depend on the ratio of the length of the

exposed perimeter of the floor divided by its area.

The exposed perimeter is measured internally and is

the length of any walls which are not heated on the

other side.

For the following P/A ratios, use the following Celotex

products:

P/A ratio = 0.87 - 1.32, use Celotex GA4065




P/A ratio = 0.32 - 0.45, use Celotex TB4045

P/A ratio = <0.32, use Celotex TB4040

NB: If using an underfloor heating system, ask us about

Celotex FF4000.

Upgrading existing internal walls:U-value requirement is 0.30 W/m²KWhen insulating a 215mm brick wall, fix GA4050 to the

wall by over battening with 25mm x 50mm battens at

600mm centres. This is fixed through the battens and

GA4050 into the wall using proprietary fixings. The

joints of the insulation are then taped using Celotex

Insulation Tape and the perimeter edges sealed with

mastic, thereby providing a vapour control layer (VCL).

Finally, fix 12.5mm plasterboard to the battens. The

above installation will provide a U-value of 0.30 W/m²K.

When insulating a 250mm uninsulated cavity wall,

follow the same procedure but use TB4045 to achieve a

U-value of 0.30 W/m²K.

When insulating a 250mm insulated cavity wall, follow

the same procedure but use Celotex TB4025 to achieve

a U-value of 0.29 W/m²K

When insulating a 103mm brick wall, first fix a breather

membrane against the wall then follow the same

procedure as mentioned previously, but use Celotex

GA4055 to achieve a U-value of 0.29 W/m²K.

Upgrading existing or constructingnew sloping ceilings: U-valuerequirement is 0.18 W/m²KWhen insulating 100mm x 50mm rafters at 400mm

centres, use Celotex GA4050 between the rafters, then

fix Celotex GA4070 beneath the rafters. The joints of the

insulation beneath the rafters are then taped using

Celotex Insulation Tape and the perimeter edges are

sealed with mastic to provide a vapour control layer

(VCL). A 25mm batten is then installed on the line of the

rafter. Finally, fix the 12.5mm plasterboard through the

battens.

When insulating 125mm x 50mm rafters at 400mm

centres, use the same fixing method as above but use

Celotex GA4075 between the rafters and Celotex

GA4050 beneath the rafters. Tape the joints of the

insulation with Celotex Insulation Tape and seal the

perimeter edge with mastic to provide a VCL. A 25mm

batten is then installed on the line of the rafter and

12.5mm plasterboard is fixed through the batten.


centres, use Celotex GA4100 between the rafters and

Celotex TB4035 beneath the rafters. In this instance no

batten is required.

In all of the above solutions you must ventilate the

50mm cavity above the insulation.

U-value achieved is 0.18 W/m²K in each case.

T: 0901 996 0100* | celotex.co.uk | 75

Upgrading existing flat roofs: U-value requirement is 0.18 W/m²KCold flat roofsWhen insulating at joist level, use a total of 165mm ofCelotex insulation between joists at 600mm centres.Always install a 1000 gauge polythene VCL beneath thejoists before fixing the 12.5mm plasterbord.

Other solutions are also available depending on howcritical headroom is. Examples include:

▶ Use Celotex GA4100 between the joists and CelotexTB4045 beneath the joists. Tape the joints of theinsulation with Celotex Insulation Tape and seal theperimeter edges with mastic to provide a VCL.Finally, install 12.5mm plasterboard to the undersideof the insulation.

U-value achieved is 0.18W/m²K.

▶ Use Celotex GA4075 between the joists and CelotexGA4050 beneath the joists. Tape the joints of theinsulation with Celotex Insulation Tape and seal theperimeter edges with mastic to provide a VCL. A25mm batten is then installed on the line of thejoists. Finally, install 12.5mm plasterboard to thebattens.


▶ Use Celotex GA4050 between the joists and CelotexGA4065 beneath the joists. Tape the joints of theinsulation with Celotex Insulation Tape and seal theperimeter edges with mastic to provide a VCL. A25mm batten is then installed on the line of the joists.Finally, install 12.5mm plasterboard to the battens.


In all of the above solutions you must ventilate the50mm cavity above the insulation.

Warm flat roofsWhen using built up roofing or asphalt as theweatherproofing layer, use Celotex TD4126 over thejoists and firrings. The board needs a noggin under allunsupported ends and a double bead of mastic up thefirrings and across the noggins wherever there is a buttjoint. U-value achieved is 0.18 W/m²K.

When using a single-ply membrane, use the sameprocedure but fix 12mm plywood above the CelotexTD4126 to achieve a U-value of 0.18 W/m²K.

Upgrading existing or constructingnew flat ceilings: requirement is0.16 W/m²KFit 100mm mineral wool or fibreglass between ceiling

joists and GA4090 over the joists to achieve a U-value of

0.16 W/m²K.

Alternatively fit Celotex GA4090 between ceiling joists

and GA4065 over the ceiling joists.

In both cases a 1000 gauge polythene membrane

should be installed beneath the ceiling joists.

Newly constructed partition wall:requirement is 0.28 W/m²K100mm dense block wall

Fix Celotex GA4060 to the wall by using 25mm x 50mm

battens at 600mm centres and proprietary fixings. Tape

the joints of the insulation with Celotex Insulation Tape

and seal the perimeter edges with mastic to provide a

VCL. Finally, install 12.5mm plasterboard to the battens.

100mm timber stud wall

Fix 12.5mm Fireline plasterboard to the outer face of

the stud wall. Install Celotex GA4070 between the studs,

flush with the back of the studs, thereby leaving a

30mm cavity, then fix Celotex TB4012 over the warm

side of the studs. The joints of the insulation are then

taped using Celotex Insulation Tape and the perimeter

sealed with mastic to provide a VCL. Finally, fix 12.5mm

plasterboard through to the studs to achieve a U-value

of 0.28 W/m²K.


76 | T: 0901 996 0100* | celotex.co.uk

Loft conversions

Upgrading existing or constructingnew sloping ceilings: U-valuerequirement is 0.18 W/m²KWhen insulating 100mm x 50mm rafters at 400mm

centres, use Celotex GA4050 between the rafters, then

fix Celotex GA4050 beneath the rafters. The joints of the

insulation beneath the rafters are then taped using

Celotex Insulation Tape and the perimeter edges sealed

with mastic to provide a vapour control layer (VCL). A

25mm batten is then installed on the line of the rafter,

on to which the 12.5mm plasterboard is then fixed

through to the battens.

When insulating using 125mm x 50mm rafters at

400mm centres, use the same fixing method as above,

but use Celotex GA4075 between the rafters and

Celotex GA4050 beneath the rafters.


centres, use Celotex GA4100 between the rafters and

Celotex TB4035 beneath the rafters. In this instance, no

batten is required.

In all of the above solutions you must ventilate the



Constructing new flat roofs: U-value requirement is 0.18 W/m²KWarm flat roofs

When using built up roofing or asphalt as the

weatherproofing layer use Celotex TD4126 over the

joists and firrings. The board needs a noggin under all

unsupported ends and a double bead of mastic up the

firrings and across the noggins wherever there is a butt

joint. U-value achieved is 0.18 W/m²K.

When using a single-ply membrane, use the same

procedure but fix 12mm plywood above the Celotex

TD4126. This will achieve a U-value of 0.18 W/m²K.

Cold flat roofs

When insulating at joist level, use a total of 200mm of

Celotex insulation to build up a 200mm thickness

between joists. Always install a 1000 gauge polythene

VCL below the joists before fixing the 12.5mm

plasterboard.

Other solutions are also available, depending upon how

critical internal headroom is. Examples include:

▶ Use Celotex XR4120 between joists and Celotex

TB4030 beneath the joists. Tape the joints of the

Celotex with Celotex Insulation Tape and seal the

perimeter edges with mastic to provide a VCL.

Finally, fix 12.5mm plasterboard to the underside of

the insulation..

▶ Use Celotex GA4100 between the joists and Celotex

TB4045 beneath the joists. Tape the joints of the



Finally, fix 12.5mm plasterboard to the underside of

the insulation.


GA4050 beneath the joists. Tape the joints of the


perimeter edges with mastic to provide a VCL. Install

a 25mm batten on the line of the joists. Finally fix

12.5mm plasterboard through the batten.


GA4070 beneath the joists. Tape the joints of the



Finally, install a 25mm batten on the line of the joists

and fix 12.5mm plasterboard to the batten.

In all of the above solutions, you must ventilate the



T: 0901 996 0100* | celotex.co.uk | 77

Upgrading existing gable wallsand party walls: U-valuerequirement is 0.30 W/m²KWhen insulating a 215mm brick wall, fix Celotex GA4050

to the wall by over battening with 25mm x 50mm

battens at 600mm centres. This is fixed through the

battens and Celotex GA4050 into the wall using

proprietary fixings. The joints of the Celotex are then

taped using Celotex Insulation Tape and the perimeter

edges sealed with mastic to provide a VCL. Finally, fix

12.5mm plasterboard through the studs to achieve a


When insulating a 250mm uninsulated cavity wall, use

the same procedure but use TB4045 to achieve a


Constructing new attic walls: U-value requirement is 0.28 W/m²KWhen insulating a 100mm stud wall, install Celotex

GA4075 between the studs, flush with the back of the

studs, thereby leaving a 25mm cavity, then fix Celotex

TB4012 over the inside face of the studs. The joints of

the insulation are then taped using Celotex Insulation

Tape and the perimeter sealed with mastic to provide a

VCL. Finally, fix 12.5mm plasterboard through to the

studs to achieve a U-value of 0.28 W/m²K.

When insulating 125mm studs use Celotex GA4100

between the studs, again leaving a 25mm cavity

between the studs, then fix a 1000 gauge polythene

membrane over the studs and seal the perimeter with

mastic to provide a VCL. Finally, fix 12.5mm plasterboard

through the studs to achieve a U-value of 0.28 W/m²K.

For 150mm studs, use Celotex GA4090 between the


Constructing new dormer face and cheeks: U-value requirement is0.28 W/m²KExternal tiling

In the case of 100mm studs with external tiling hung over

a breather membrane on top of 12mm sheathing ply, use

Celotex GA4070 between the studs, leaving a 30mm

cavity between the studs. Then, over the inside face of the

studs fix Celotex TB4012, taping the joints using Celotex

Insulation Tape and the perimeter edges sealed with

mastic to provide a VCL. Finally, fix 12.5mm plasterboard

through the studs to achieve a U-value of 0.28 W/m²K.

External render

In the case of 100mm studs with an external renderfinish, use the same procedure with Celotex GA4070between and Celotex TB4012 over the face to achieve aU-value of 0.28 W/m²K.

External weatherboarding

In the case of 100mm studs with external

weatherboarding fixed over battens and a breather

membrane to create a ventilated space over a 12mm

sheathing ply, install Celotex GA4070 between the studs.

Then over the inside face of the studs fix Celotex

TB4012, taping the joints using Celotex Insulation Tape

and the perimeter edges sealed with mastic to provide

a VCL. Finally, fix 12.5mm plasterboard through the


Upgrading existing or constructingnew flat ceilings: U-valuerequirement is 0.16 W/m²KFit Celotex GA4090 between ceiling joists and CelotexGA4065 over the ceiling joists to achieve a U-value of0.16 W/m²K.

Alternatively, fit 100mm mineral wool or fibreglassbetween ceiling joists and Celotex GA4090 over the joiststo achieve a U-value of 0.15W/m²K.

In both cases a 1000 gauge polythene membraneshould be installed beneath the ceiling joists prior tofixing the plasterboard.


78 | T: 0901 996 0100* | celotex.co.uk

General information

Characteristics, properties or performance of materials described herein are derived from data obtained under controlled test conditions. CelotexLimited makes no warranty, express or implied as to their characteristics under any variations from such conditions in actual constructions.All products are supplied subject to our standard terms and conditions of sale, a copy of which is available on request.Typical details shown in this brochure are provided for guidance only and are not to scale. Celotex Limited makes no warranty, express or implied asto the suitability of such details for any particular project. It is the responsibility of the designer to ensure that any design or construction details usedare suitable for the project, having due regard to the environmental and structural factors which are beyond the control of Celotex Limited.Notwithstanding the foregoing, nothing herein stated shall exclude or restrict:1. The liability of Celotex Limited in respect of death or personal injury pursuant to the relevant provisions of the Unfair Contract Terms Act 1977, or2. The liability of Celotex Limited in respect of any damage caused by a defect to the extent that such comes within the relevant provisions of the

Consumer Protection Act 1987.

* Calls are charged at 30p per minute from a BT landline and lines are open Monday – Friday from 8:00am – 5:15pm.Details and pricing are correct at date of publication – November 2010.

Storage and handling▶ Celotex insulation boards should be stored dry, flat

and clear of the ground. Only as much material as

can be installed during a single working period

should be removed from storage at any one time. If

boards are stored under tarpaulins, care should be

taken to prevent rope damage to the boards.

▶ Care should also be taken to ensure that packs are

not dropped onto corners or edges.

▶ Where possible, cut the product using the Celotex

Insulation Saw to minimise dust creation.

▶ When cutting Celotex insulation, dust extraction

equipment, eye protection and face masks must be

worn. Dust or particles in the eyes should be

washed out with liberal quantities of water.

▶ Aluminium foil edges may be sharp. Avoid sliding

bare hands along board edges.

For a downloadable copy of our Health & Safety

guidelines, please visit the website at celotex.co.uk

Waste management and recyclingCelotex continually monitors the levels of waste from its

activities and drives and implements procedures which

reduce the amount of waste produced. The company

ensures that all employees are aware of the importance

of reducing waste in all activities.

The majority of Celotex products are packaged without

the requirement for shrink wrap and instead use

recyclable materials such as cardboard banding.

Waste PIR is inert and land fill safe with no known effect

on ground water. Glass fibre used as core reinforcement

in certain products is made up almost entirely from

recycled waste glass.

Celotex’ environmental impact has been assessed via a

BRE Environmental Profile. This profile drives our A+

Green Guide rating and considers the full ‘cradle to

grave’ impact including raw material extraction,

manufacture, transportation, performance in use and

disposal.

For further information on the Sustainability credentials

of Celotex including a copy of our Environmental &

Sustainability Statement, please visit the ‘Sustainability’

pages of celotex.co.uk

We know insulation inside and out

When it comes to insulation, nothing can be more impressive than the igloo - keeping the warmth in and the cold out in some of the earth’s harshest environments. And now, the innovative FR4000 from Celotex also demonstrates unrivalled insulation properties, featuring ground-breaking technology and is today at the forefront of PIR insulation.

FR4000 is poles apart from other products in terms of thermal efficiency with a low lambda of 0.022 W/mK,offering you improved U-values, and leads the way in terms of sustainability. FR4000 has an extremely lowGlobal Warming Potential and achieves an ‘A’ rating when compared to the BRE Green Guide 2008. Andas if that wasn’t reason enough to specify FR4000, we’ve taken insulation specification to the extreme,offering Class O fire performance throughout the entire product.

Thanks to the pioneering spirit of all our researchers, scientists and technicians, we’ve achieved a giant leap in insulation innovation. Never before has one product offered so much. So specify the best, specify FR4000.

Discover more at celotex.co.uk/FR4000 and request your free sample.

FR4000. When only the best insulation will do.

FR4000 SpecificationPremium thermal performance

0.022 W/mK lambda

BRE Green Guide A rated

Low GWP and zero ODP

Class O fire performance

✓

✓✓

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celotex.co.uk/FR4000

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We know insulation inside and out

Celotex Technical CentreT: 0901 996 0100* F: 01473 820889

Contact us at celotex.co.uk

Celotex SalesT: 01473 820820 F: 01473 828857 E: [email protected]

Celotex LimitedLady Lane Industrial Estate Hadleigh Ipswich Suffolk IP7 6BA

Registered in England No. 2183896

Documents

CL0205 Handy Guide update v2 - Nevill Long · 52 Single timber frame wall lining and dormer cheeks 54 Timber frame wall sheathing ... Scotland Domestic Technical Handbook – Section