Catnic Lintels Design Guide

Lintel Technical Guide

March 2002

Catnic

March 2002

Cl/Sfb (31.9) Hh2 (Y2)

2 Lintel Technical Guide

About CorusCorus is a major European producer of steel andaluminium. Our multi-metals approach is one of theunique features of the company, and is at the heart ofour strategy. Many things we use in our daily lives hasin some way involved metal in its creation. We workwith automotive and packaging designers, architects,a broad range of engineers, and with those whoseprofession is product and industrial design.

Corus was formed on the

6 October 1999, through the merger

of British Steel and Knoninklijke

Hoogovens to create an innovative

metals company, which combines

international expertise with a first

class service.

Corus Business units deliver more

than high-quality metal products.

They are active business partners,

helping customers identify and take

advantage of new opportunities.

Through the business units,

customers gain access to a global

network of knowledge and expertise

to help optimise their own

processes and products.

Thanks to our business units Corus

supplies and manufactures a wide

range of steel and aluminium

products to the construction industry

world wide, including building

envelope systems, light structural

elements and aluminium and wall

cladding systems.

Systems and services include:

Building envelope systems

Roof and wall cladding systems

Curtain walling

Trapezoidal sheets for cladding

Composite panels for cladding

Roof deck profiles

Composite floor deck profiles

Light structural elements (lintels,

building components and framing)

Industrial doors

Flashings and accessories

Perforated coil and sheet products

For further information visit www.corusgroup.com

4 Product and Service Benefits

5 Selecting the Right Lintel

7 Installing a Catnic Lintel

8 Open Back Lintels

16 Combined Box Lintels

23 Closed Eaves Lintels

27 CXL Lintels

30 Timber Frame Lintels

33 External Solid Wall Lintels

37 Internal Solid Wall Lintels

41 Feature Lintels

45 Accessories

48 Where to use a separate DPC

48 Quality Assurance

49 Technical Information

49 Health and Safety

50 Technical Specification

50 Glossary of Technical Terms

51 Technical Enquiry Request Form

Contents

About CatnicCatnic specialises in the manufacture and supply ofsteel lintels, building components, plasterers beadsand fence post support systems of the very higheststandard and quality.

Our reputation for the superior quality of our

products has been earned through constant

technical innovation and development. Choosing

a Catnic product from our comprehensive range

assures peace of mind and complete confidence

in the finished job.

Additionally, our sales and technical service teams are

dedicated to matching the quality of our products with

the excellence of our service. Sales and technical support

staff are friendly, helpful and highly professional.

Catnic is committed to providing the building industry

with a steady supply of new and improved products

borne from our investment in design and

manufacturing technology. This brochure gives

an overview of our Lintels product range along with

comprehensive technical and specification data. Details

of our Building Component range and Fence Post

Support Systems can be found in separate brochures

available on request from the telephone number

given below.

We hope that you will find the

information in the following pages

both useful and informative, but if

you require any further assistance,

please call 029 2033 7900.

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Lintel Technical Guide 3

Lintel BenefitsDuplex corrosion protectionMany Catnic lintels employ not just one but twomethods of protection against corrosion attack: theunique, sophisticated Duplex double protection system.

1st corrosion protection layer galvanised steel 2nd corrosion protection layer polyester coating

The lintels are manufactured from hot-dipped galvanisedsteel to BS EN10142: 2000 of grade DX51D & Z275 witha black coloured polyester resin finish. The protectionsystem complies fully with the chemical and physical testrequirements outlined in Table 2 of BS 5977: PART 2: 1983for lintels effectively having their own built-in DampProof Course.

This double method of protection gives Catnic lintelsinherent benefits over those offered by othermanufacturers using the more traditional pre- or post-galvanised steel techniques. Both these processes relyon just a simple coating of zinc to provide cathodicprotection. The zinc protects the steel but is itself liableto rust with aqueous alkaline solutions leaching from thebuilding fabric and therefore corrode. The polyestercoating in the Catnic process provides an effectivebarrier against moisture or chemical attack leached fromthe masonry construction.

Service BenefitsTechnical supportCatnic offers a free advisory service to designers,specifiers and contractors, engaged on any buildingproject, whatever its size, from a private houseextension to a major new commercial or industrialdevelopment.

Free scheduling serviceCLASS the Catnic Lintel Advanced Scheduling Serviceis the most comprehensive lintel scheduling serviceavailable to builders and specifiers.

In one clear, easy to understand document, CLASSprovides all the information and guidance needed forevery stage of a job. Right from the architect andspecifier stage through to the actual on-site operation,CLASS leaves no room for confusion ormisunderstanding by clearly showing:

a description of each lintel with its location and list price

structural calculations, where necessary

To access the benefits of CLASS, simply send theproject drawings (plans, sections and elevations) to our Technical Services Department (please seeenquiry form in the back of this brochure).

Freepost Scheduling ServiceCustomers are given a large reply-paid envelope intowhich they put the details of the contracts they areworking on. A checklist printed on the outside of theenvelope ensures that no relevant information isforgotten, thereby ensuring a speedy and accurateresponse. This information will typically include: detailsof the type of contract (flat, housing, industrial,extension, etc); wall construction details; floor and roofspecification details; plans, elevations and sections asnecessary.

The envelope is then returned to Catnics TechnicalServices Department who will draw up a clear, easy tounderstand document, providing a detailed schedule forevery stage of the job.

This service is provided free of charge.

Free advice and design serviceCatnic is always ready to assist by answering queries onany technical or practical aspects of the specification orinstallation of lintels. We also welcome the opportunityto participate in the design and specification of speciallintels to suit individual requirements. For full details ofour design and manufacturing service for special lintels,please contact our Technical Services Department.

Telephone Technical Services on029 2033 7900

or alternatively fax your enquiry on029 2086 0135

Load RatiosSafe working loads, as defined by BS 5977: Part 2 forcavity wall lintels refer to uniform distributed loadsapplied in the inner to outer leaf ratios:

1:1 For lintels supporting masonry only 3:1 For lintels normally carrying timber floors 5:1 For lintels normally carrying concrete floors

The CU lintel range refers to uniformly distributed loadsin the ratio of 19:1 when non standard or unusualloading conditions occur.

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How to Select a Cavity Wall Lintel

How to Select a Catnic LintelTo select a Catnic lintel, you need toknow three things:

1 The wall construction2 The length of lintel required3 The load to be placed on the lintel

1. Wall ConstructionIf you know the wall construction, seethe Lintel Selection Index on page 6 tofind the correct lintel type. Alternatively,please refer to the wall constructiontypes below:

Cavity WallIf the construction is a cavity wall, seethe Open Back lintel section on page9, or the Combined Box lintel sectionon page 16. You will need to know thecavity wall dimensions to choose thecorrect lintel, ie. the external leafdimension, the cavity dimension andthe internal leaf dimension. Also,please refer to the table How to Selecta Cavity Wall Lintel below.

Timber FrameFor timber frame constructions, youneed to know the external leafdimension and the cavity dimension there is no internal leaf. Once you have

these dimensions, please refer to theTimber Frame lintels section on page 31.

External Solid WallThere are three forms of lintel forexternal solid walls: single element lintels for a single leaf

of brickwork two-piece lintels shaped to carry the

two separate leaves of a 215mm fairface brick wall

box profile lintels which have a toefor use in solid brick or block wallsfrom 200mm 215mm thick

Lintels suitable for use in external solidwall constructions can be found onpage 34.

Internal Partition and Load BearingWall Lintels for internal partitions and loadbearing walls come in three styles: corrugated lintels for non-load

bearing applications channel section lintels for loadings

involving floor joists or blockwork box profile lintels for heavier loads

including point loads and wideropenings

These lintels are featured on page 38.

2. Lintel LengthThe length of lintel required iscalculated by establishing the totalwidth of the structural opening andadding 150mm (200mm for CXL lintels)end bearing allowance for each end.For example, an 1800mm structuralopening will require a 2100mm lintel(2200mm for CXL).

3. Applied LoadAll lintels are designed to carry aspecific safe working load. If you are not skilled in the method of loadassessment, or the load has not beensupplied to you by a third party, thenplease contact Catnic TechnicalServices on 029 2033 7900 for advice.

Once you have established your wallconstruction, lintel length and appliedload you will be able to choose theperfect Catnic lintel for your job byreferring to the relevant tables in thisbrochure.

Lintel Selector

100m

m

115m

m12

5mm

140m

m

50-65 Pg 70-85 Pg 90-105 Pg

Cavity (mm)

Inner Block size (mm)

CG50/100 10CGH50/100 10

CG70/100 12CGH70/100 12

CG90/100 14CGH90/100 14

CU50/100 10 CU90/100 14

CG50/100 10CGH50/100 10

CG70/100 12CGH70/100 12

CG90/100 14CGH90/100 14

CU50/100 10 CU70/100 12 CU90/100 14

CG50/125 11CGH50/125 11

CG70/125 13CGH70/125 13

CG90/125 15CGH90/125 15

CU50/125 11 CU70/125 13 CU90/125 15

CG50/125 11CGH50/125 11

CG70/125 13CGH70/125 13

CG90/125 15CGH90/125 15

CU50/125 11 CU70/125 13 CU90/125 15

CN11 21CN12 21

CN57 22CN58 22

CN7 17CN8 17

CN3 18CN4 18

CN14 19

CN3 18CN4 18

CN3* CN4* 18CN14** 19

CN43 20CN44 20

CU70/100 12

Lintels illustrated above are based on 102mm masonry outer leaf

* Not suitable for 75-85mm cavities ** Not suitable for 70mm cavity


Lintel IndexOuter Leaf Cavity Inner Leaf Lintel Codes Lintel Application Page

102 50-65 100-115 CG50/100 Open Back Lintel 10

102 50-65 100-115 CGH50/100 Open Back Lintel 10

102 50-65 100-115 CU50/100 Open Back Lintel 10

102 50-65 125-140 CG50/125 Wide Inner Leaf Open Back Lintel 11

102 50-65 125-140 CGH50/125 Wide Inner Leaf Open Back Lintel 11

102 50-65 125-140 CU50/125 Wide Inner Leaf Open Back Lintel 11













102 50-65 100 CN7, CN8 Combined Box Lintel 17



102 75-90 115 CN14 Combined Box Lintel 19

102 90-105 100 CN14 Combined Box Lintel 19

102 50 100-115 CN41, CN42 Combined Box Lintel Wide Outer Leaf 19

102 50-65 125 CN43, CN44 Combined Box Lintel Wide Inner Leaf 20




102 75 135-150 CN57 Combined Box Lintel Wide Inner Leaf 22

102 75 135-150 CN58 Combined Box Lintel Wide Inner Leaf 22

N/A 50-85 100-115 CGE50/100 Open Back Eaves Lintel 25

N/A 50-85 125-140 CGE50/125 Wide Inner Leaf Open Back Eaves Lintel 25

N/A 90-105 100-115 CGE90/100 Open Back Eaves Lintel 25

N/A 90-105 125-140 CGE90/125 Wide Inner Leaf Open Back Eaves Lintel 25

N/A 50-75 100 CN55 Combined Box Eaves Lintel 26

102 50 100-115 CXL240 Extreme Heavy Duty Lintel 29

102 50-70 100-140 CXL265 Extreme Heavy Duty Lintel 29

102 70-90 100-140 CXL290 Extreme Heavy Duty Lintel 29

102 50-60 CTF5 Timber Frame Lintel 32

102 35-60 CN23 Timber Frame Lintel 32

200-215 CN71, CN81 External Solid Wall 35

102 CN48, CN49 External Solid Wall 36

102 CNZ94, CNZ95, CNZ96, CNZ97 External Solid Wall 36

215 CN50, CN51 External Solid Wall 36

N/A 75 CN92 Internal Partition Lintel 39



N/A 100 CN5X, CN6X Internal Partition Lintel 39

N/A 140-150 CN56X, CN66X Internal Partition Lintel 40


Installing a Catnic lintel

In cavity walls, raiseinner and outer leavessupported by linteltogether.

Ensure walldimensions are correct.

Ensure that masonryoverhang does notexceed 25mm.

Masonry above lintelsshould be allowed tocure before applyingfloor or roof loads.

Ensure lintel is level along its width.

Ensure lintel isnot damaged.

Ensure lintel is fullybed on bricklayingmortar.

Ensure lintel is level along its length.

Structural opening

* For advice on installations where endbearings can be reduced to not less than100mm, please contact Catnic TechnicalServices.

Ensure no more than half the safe workingload (SWL) is carried by the outer leaf wherethe lintel carries an external cavity wall. Thewall should also be restrained laterally nearthe top.

Outer Leaf Inner LeafCavity

Ensure a nominal150mm end bearingat each end.*

Additional Notes

Do Install a separate DPC in severe exposure conditions. A Catnic Open Back or Combined Box lintel with an additional DPC membrane installed in accordance with normal practice provides the best possible protection.

Locate the window/door frame so that the drip on the front of the lintel projects forward of the drip on the front of the frame. It is good building practice to insert a flexible joint between the lintel and the top of the frame.

Ensure that point loads are not applied directly to the flanges of lintels. Timber floor joists and roof trusses should have a full block depth between them and the lintel flange.

Refer to the Steel Lintels Manufacturers Associations leaflet Recommendations for the Installation of Concrete Floors with Steel Lintelswhen using Open Back lintels to support concrete floors.

Consider the use of our soffit cladding for all coastal sites (refer to pages 47/48).

Dont Use damaged lintels.

Apply point loads without prior consultation. Where the loading or a substantial part of it is applied as concentrated loads, each concentrated load must be supported over a length of lintel of not less than 200mm. In such cases, the total loading must not produce bending movements or shear forces greater than those produced by the uniformly distributed loads specified in the relevant data tables.

Allow blockwork to overhang the lintel by more than 25mm.

Apply concrete floor loads without ensuring that the total loads are checked by a structural engineer, or by Catnic Technical Services.

Catnic Cavity Wall LintelsTwo styles available for use in cavity wall construction:Catnic Open Back and Combined Box lintelsincorporating insulation, built-in plaster key and built-in DPC.


Open Back Lintels

Typical Applications

CG

Triangulated masonry load

Supporting uniformly distributed masonry load

Supporting uniformly distributed timber floor and

roof loads

Suitable for fair faced inner leaf masonry

CGH

As above plus:

Increased loading conditions

Uneven loading situations

Nominal point loading eg. stair trimmers, stud

partition supports, etc.

CU

As above plus:

Supports concrete floors

Attic truss loads

Larger span multiple truss loads

Increased point loading eg. steel beams, etc.

Available for longer length applications

Conditions of Use

Nominal 150mm end bearings

Both leaves are raised together

One course of block prior to installation of floor/roof

Refer to Installing a Catnic Lintel (page 7)

Note: For a definition of these terms see the Glossary

of Technical Terms on page 50

Isometric view of a typical Catnic CG lintel over a timber window.


CG Lintel

CU Lintel

NOTE: Whilst the above information is intended to offer general guidance regarding typical applications, it should not be considered ascomprehensive. Requirements not fully covered by the above should be referred to our technical services department for individual consideration.

An economical solution for domestic and commercial uses.

Benefits

Materials used in Open Back Lintels

The CG, CGH and CU ranges are formed from

galvanised steel, then powder coated.

Integral insulation

Maximising thermal efficiency, minimising cold

bridging.

Duplex corrosion protection

Ensures optimum durability and longevity.

Easy-to-use open back profile

Allows masonry to be built up continuously on both

outer and inner leaf.

Built-in DPC

Saves time in construction, and means cavity is easy

to clean without risk of damage to DPC.

Built-in plaster key

With staggered slots applied to the inner flange and

ribbed underside of insulation (perforated steel

baseplate on CU range only).

Accessories

ArchCentres, Stop Ends, Cavity Weep Vents, Soffit

Cladding (refer to page 46/47).


Cavity WallsOpen Back

CG50/100

Standard lengths (mm) 750-1500 1650-1800 1950-2100 2250-2400 2550-2700 3000 3300-3900

SWL 1:1/3:1 (kN) 15 18 20 22 26 26 26

Weight (kg/m) 5.80 7.34 7.96 8.59 9.84 12.29 16.02

Nominal height h (mm) 140 140 160 180 220 220 220

CGH50/100

Standard lengths (mm) 900-1200 1500 1800 2100

SWL 1:1/3:1 (kN) 23 29 34 40

Weight (kg/m) 9.5 11.1 14.2 16.2

Nominal height h (mm) 140 180 180 220

CU50/100

Standard lengths (mm) 750-3000 3300-3900 4200-4800

SWL 1:1/3:1 (kN) 74 47 29

5:1/19:1(kN) 75 51 31

Weight (kg/m) 19.4 19.4 19.4

Nominal height h (mm) 232 232 232

For 50-65mm Cavity 100-115mm Inner Leaf

nominalheight (seetables below)

CG & CGH CU

95 48 100

48 100

hh

95

Continuous solid infill block

Concrete Floor LoadsWhen using the Catnic CU Open Back range with concrete floors, always ensure that the blockwork is built tight against the inner vertical face of the lintel, and that a mortar joint isadded to the top of the blockwork so that the floor units have an even spread over the inner flange of the lintel.

CG Lintel

Standard lengths are available in increments of 150mm at lengths up to 3000mm, 300mm at lengths from 3000mm 4800mm (including 4575mm, but excluding 4500mm)

The SWL (safe working load) is based on the total UDL (uniform distributed load) over maximum span using 150mm end bearings

CGH Lintel CU Lintel

Note: To achieve the CU loading figures indicated, lintels

must be built-in as illustrated, ensuring that the blockwork

infill is well-jointed during construction and compatible

with the strength of the masonry above.

Continuoussolid infillblock

CG50/125*

Standard lengths (mm) 750-1200 1350-1800 2100-2400 2550-2700 3000

SWL 1:1/3:1 (kN) 12 17 20 26 26

Weight (kg/m) 6.3 7.78 9.03 12.87 16.55

Nominal height h (mm) 140 140 180 220 220




* For applications incorporating 140mm solid aggregate concrete blocks, contact our Technical Services Department on 029 2033 7900

CGH50/125*


SWL 1:1/3:1 (kN) 23 29 34 40

Weight (kg/m) 10.0 11.6 14.8 16.8


CU50/125


SWL 1:1/3:1 (kN) 74 47 29

5:1/19:1(kN) 75 51 31

Weight (kg/m) 19.7 19.7 19.7


Cavity WallsOpen Back Wide Inner Leaf

For 50-65mm Cavity 125-140*mm Inner Leaf


CG & CGH

95 48 125

h






CG Lintel CGH Lintel CU Lintel

CU

48 125

h

95





CG70/100

Standard lengths (mm) 750-1500 1650-1800 1950-2100 2400 2550-2700 3000 3300-3900

SWL 1:1/3:1 (kN) 15 18 20 22 26 26 26

Weight (kg/m) 5.98 7.48 8.1 8.7 9.98 12.46 16.29


CU70/100


SWL 1:1/3:1 (kN) 74 47 29

5:1/19:1(kN) 75 51 31

Weight (kg/m) 19.7 19.7 19.7


CGH70/100


SWL 1:1/3:1 (kN) 23 29 34 40

Weight (kg/m) 9.7 11.3 14.5 16.5




CG & CGH

95 68 100

h









CU

68 100

h

95




CG70/125*

Standard lengths (mm) 900-1200 1500-1800 2100-2400 2700 3000

SWL 1:1/3:1 (kN) 12 17 20 26 26

Weight (kg/m) 6.33 7.95 9.18 13.07 16.9





CG & CGH

95 68 125

h

CU70/125


SWL 1:1/3:1 (kN) 74 47 29

5:1/19:1(kN) 75 51 31

Weight (kg/m) 19.9 19.9 19.9


CGH70/125*


SWL 1:1/3:1 (kN) 23 29 34 40

Weight (kg/m) 10.2 11.8 15.1 17.1











CU

68 125

h

95







CG & CGH

95 88 100

h

CG90/100

Standard lengths (mm) 750-1500 1650-1800 1950-2100 2400 2550-2700 3000 3300-3900

SWL 1:1/3:1 (kN) 15 18 20 22 26 26 26

Weight (kg/m) 6.13 7.63 8.26 8.88 10.15 12.96 16.6


CU90/100


SWL 1:1/3:1 (kN) 74 47 29

5:1/19:1(kN) 75 51 31

Weight (kg/m) 19.8 19.8 19.8


CGH90/100


SWL 1:1/3:1 (kN) 23 29 34 40

Weight (kg/m) 10.0 11.6 14.8 16.8










CU

88 100

h

95







CG & CGH

95 88 125

h

CG90/125*


SWL 1:1/3:1 (kN) 12 17 20 26 26

Weight (kg/m) 6.5 8.13 9.36 13.28 17.2


CU90/125


SWL 1:1/3:1 (kN) 74 47 29

5:1/19:1(kN) 75 51 31

Weight (kg/m) 20.1 20.1 20.1


CGH90/125*


SWL 1:1/3:1 (kN) 23 29 34 40

Weight (kg/m) 10.4 12.0 15.4 17.4











CU

88 125

h

95




Combined Box Lintels

Typical Applications

Universal application caters for all loading

conditions

Direct floor or roof loading

Supports concrete floor loads

Attic truss loads

Supports points loads eg. steel beams, etc.

Optional 4 course profile for high loads at extended

spans

Conditions of Use

Nominal 150mm end bearings

Lintel features

Catnic Combined Box lintels incorporate full height

expanded polystyrene insulation along the complete

lintel length, secured within the box section to prevent

damage on site. This range also includes lintel profiles

designed for closed eaves applications.

Integral insulation

Maximising thermal efficiency.

Minimal cold bridging

Staggered slots in base plate minimises cold bridging.



Isometric view of a typical combined box lintel supporting a concrete floor.

Built in DPC

Saves time in construction, and means cavity is easy

to clean without risk of damage to DPC.

Box profile

Provides savings on blockwork and installation costs.

Instant full load use

The Combined Box profile is designed to carry a full

load of wet masonry as soon as it is installed.

Tried and trusted

Over 30 years success.

Accessories



IMPORTANT NOTE:

When using the Combined Box Lintel with concrete floors,

always ensure that a mortar joint is added to the top of

the blockwork so that the floor units have an even spread

over the inner flange of the lintel.

A cost effective solution for all types of building construction including housing, multiplestorey, commercial, etc.

NOTE: Whilst the above information is intended to offer general guidance regarding typical applications, it should not be considered ascomprehensive. Requirement not fully covered by the above should be referred to our technical services department for individual consideration.


Cavity WallsCombined Box


CN8B CN8C

Standard lengths (mm) 2700-3600 1800-2700 2850-3300 3600 3900-4575 4800

SWL 1:1/5:1 (kN) 29 54 47 39 29 25

Weight (kg/m) 15.8 19.2 19.2 19.2 19.2 19.2

Nominal height h (mm) 219 219 219 219 219 219

Ixx (cm4) 1388 1686 1686 1686 1686 1686

Zxx (cm3) 110 137 137 137 137 137

Serviceability moment (kNm) 17.8 22.2 22.2 22.2 22.2 22.2

CN7 & CN8

95

h

50 100

For 50-65mm Cavity 100mm Inner Leaf

CN8 LintelCN7 Lintel

CN7A CN7C

Standard lengths (mm) 750-1500 1650-2100 2250-2700 750-1500 1650-2100 2250-2700

SWL 1:1/5:1 (kN) 29 27 20 49 44 37

Weight (kg/m) 9.9 9.9 9.9 14.9 14.9 14.9


Ixx (cm4) 412 412 412 637 637 637

Zxx (cm3) 49 49 49 76 76 76


Standard lengths are available in increments of 150mm at lengths up to 3000mm, 300mm at lengths from 3000mm 4800mm (including 4575mm but excluding 4500mm)




CN4B CN4C


SWL 1:1/5:1 (kN) 29 54 47 39 29 25

Weight (kg/m) 16.1 20.4 20.4 20.4 20.4 20.4


Ixx (cm4) 1426 1730 1730 1730 1730 1730

Zxx (cm3) 112 140 140 140 140 140


For 70-85mm Cavity50-65mm Cavity

100mm Inner Leaf115mm Inner Leaf


CN3 & CN4

95

h

70 100

CN3A CN3C


SWL 1:1/5:1 (kN) 26 24 20 49 44 36

Weight (kg/m) 10.2 10.2 10.2 16.0 16.0 16.0


Ixx (cm4) 434 434 434 641 641 641

Zxx (cm3) 51 51 51 77 77 77







CN41B CN42C

Standard lengths (mm) 750-2100 2250-4200

SWL 1:1/5:1 (kN) 20 29

Weight (kg/m) 14.2 20.5

Nominal height h (mm) 143 219

Ixx (cm4) 552 1834

Zxx (cm3) 60 143

Serviceability moment (kNm) 9.8 23.2

100-115mm Inner LeafFor 140-150mm Outer Leaf 50mm Cavitynominalheight (seetables below)

CN41 & CN42

130

h

50 100

CN14A CN14C


SWL 1:1/5:1 (kN) 29 47 39 29 25

Weight (kg/m) 13.1 20.0 20.0 20.0 20.4


Ixx (cm4) 1132 1740 1740 1740 1740

Zxx (cm3) 86 138 138 138 138

Serviceability moment (kNm) 14.0 22.5 22.5 22.5 22.5




CN14

95

h

90 100



Combined Box Wide Outer Leaf



CN44B CN44C


SWL 1:1/5:1 (kN) 29 54 47 39 29 26

Weight (kg/m) 16.5 20.2 20.2 20.2 20.2 20.2


Ixx (cm4) 1492 1836 1836 1836 1836 1836

Zxx (cm3) 119 152 152 152 152 152





CN43 & CN44

95

h

50 125

Cavity WallsCombined Box Wide Inner Leaf

CN43A CN43C


SWL 1:1/5:1 (kN) 29 27 20 49 44 37

Weight (kg/m) 10.4 10.4 10.4 16.5 16.5 16.5


Ixx (cm4) 415 415 415 690 690 690

Zxx (cm3) 49 49 49 85 85 85







CN12C

Standard lengths (mm) 1800-2700 2850-3300 3600 3900-4575 4800

SWL 1:1/5:1 (kN) 54 47 39 29 26

Weight (kg/m) 20.5 20.5 20.5 20.5 20.5


Ixx (cm4) 1878 1878 1878 1878 1878

Zxx (cm3) 158 158 158 158 158





CN11 & CN12

95

h

50 140

CN11A CN11C


SWL 1:1/5:1 (kN) 29 27 20 49 44 37

Weight (kg/m) 10.8 10.8 10.8 16.8 16.8 16.8


Ixx (cm4) 425 425 425 721 721 721

Zxx (cm3) 49 49 49 90 90 90






CN58C

Standard lengths (mm) 1800-2700 2850-3300 3600 3900-4575 4800

SWL 1:1/5:1 (kN) 54 47 39 26 26

Weight (kg/m) 21.9 21.9 21.9 21.9 21.9


Ixx (cm4) 1812 1812 1812 1812 1812

Zxx (cm3) 145 145 145 145 145


CN57A CN57C


SWL 1:1/5:1 (kN) 25 22 20 49 44 37

Weight (kg/m) 11.1 11.1 11.1 17.7 17.7 17.7


Ixx (cm4) 416 416 416 748 748 748

Zxx (cm3) 46 46 46 92 92 92


135-150mm Inner LeafFor 75mm Cavitynominalheight (seetables below)

CN57 & CN58

95

h

75 140





Catnic Cavity Wall Eaves LintelsTwo styles available for use in cavity wall constructionfor closed eaves applications: Catnic Open Back andCombined Box eaves lintels incorporating insulationand built-in plaster key.


Closed Eaves LintelsOpen Back Eaves Lintels

Closed eaves lintels are manufactured from galvanised

steel and powder coated for extra protection. Available

in both open back or combined box styles.

Integral insulation

Maximising thermal efficiency, minimising cold

bridging.

Extra corrosion protection


Easy-to-use open back profile

Allows masonry to be built up continuously on

inner leaf.


With staggered slots to the inner flange and ribbed

underside of insulation.

Extended durability

Duplex system providing twice the protection.


* To achieve the stated safe working load

(SWL), closed eaves lintels must be built in

with solid blockwork and continuous timber

wall-plates. Allow 150mm at each end for

bearing support.

Closed EavesOpen Back

CGE50/100


SWL (kN)* 25 22 20

Weight (kg/m) 7.0 8.0 10.2


CGE50/125


SWL (kN)* 25 25 25

Weight (kg/m) 8.3 9.3 11.9





CGE50/100

60 48 100

h

CGE50/125

60 48 125

h

CGE90/100


SWL (kN)* 25 22 20

Weight (kg/m) 7.7 8.3 10.7


CGE90/125


SWL (kN)* 25 25 25

Weight (kg/m) 8.8 9.7 11.7




CGE90/100

60 88 100

h

CGE90/125

60 88 125

h

* To achieve the stated safe working load (SWL), closed eaves lintels must be built in with solid blockwork and continuous timber wall-plates. Allow 150mm at each end for bearing support.

Standard lengths are available in increments of 150mm


Closed EavesCombined Box

CN55A CN55C


SWL (kN) 30 25 20 50 40 30

Weight (kg/m) 9.0 9.0 9.0 12.8 12.8 12.8



h

75 100

For 50-75mm Cavity 100mm Inner LeafCN55

Eaves Lintel

Standard lengths are available in increments of 150mm

Catnic Cavity Wall CXL Fabricated LintelsA range of lintels designed for use in cavity wallconstruction for extreme loading conditions.


CXL LintelsLintels for extreme loads

Designed for external cavity walls when extreme loads

are imposed.

Longer spans

High loads at longer spans.

Varying widths

Suits a variety of wall widths with special widths on

application.

Material used

Supplied in post galvanised finish. Lintels

manufactured from a universal beam section and

6.0mm structural grade steel plate Grade S275 to

BSEN 10025:1993 and hot dip galvanised after

manufacture to BSEN ISO1461:1999.

Standard increment lengths

Overall lengths are available in 150mm increments for

lengths up to 3000mm, and in 300mm increments for

lengths from 3000mm to 6600mm (excluding

4500mm). For longer lengths to support heavy loads,

please refer to our Technical Services Department on

029 2033 7900.


As an optional extra, CXL lintels can be supplied with

expanded metal mesh secured to the base plate.

Load ratios

To achieve the loading figures shown, the lintel must

be laterally restrained and have 200mm end bearing

supports and inner to outer load ratios beween 5:1

and 19:1.

Separate DPC

A separate flexible DPC must be installed during

construction.


Applications

Lintel codes Outer Leaf Cavity Inner Leaf

CXL240 102 50 100-115

CXL265 102 50 125-140

CXL265 102 70 100-115

CXL290 102 70 125-140

CXL290 102 90 100-115

Note: For other cavity wall constructions please contact our Technical Services

Department on 029 2033 7900.


Cavity Walls

For 50mm Cavity 100-115mm Inner Leaf

133

234

240

6

CXL240

213

133

259

265

6

6

CXL265

213

133

284

290

6

6

CXL290

CXL240

Standard lengths (mm) 2100-3000 3300-4800 5100 5400 5700 6000 6300 6600

SWL 5:1/19:1 (kN) 88 83 78 71 64 56 52 47

Weight (kg/m) 41.1 41.1 41.1 41.1 41.1 41.1 41.1 41.1

Nominal height h (mm) 213 213 213 213 213 213 213 213

Ixx (cm4) 4051 4051 4051 4051 4051 4051 4051 4051

Zxx (cm3) 303 303 303 303 303 303 303 303

Serviceability moment (kNm) 50 50 50 50 50 50 50 50

Allowable reaction (kN) 68 68 68 68 68 68 68 68

CXL265


SWL 5:1/19:1 (kN) 88 83 78 71 64 56 52 47

Weight (kg/m) 42.3 42.3 42.3 42.3 42.3 42.3 42.3 42.3


Ixx (cm4) 4139 4139 4139 4139 4139 4139 4139 4139

Zxx (cm3) 305 305 305 305 305 305 305 305

Serviceability moment (kNm) 50.3 50.3 50.3 50.3 50.3 50.3 50.3 50.3


CXL290


SWL 5:1/19:1 (kN) 88 83 78 71 64 56 52 47

Weight (kg/m) 43.5 43.5 43.5 43.5 43.5 43.5 43.5 43.5


Ixx (cm4) 4222 4222 4222 4222 4222 4222 4222 4222

Zxx (cm3) 307 307 307 307 307 307 307 307

Serviceability moment (kNm) 50.6 50.6 50.6 50.6 50.6 50.6 50.6 50.6


Standard lengths are available in increments of 150mm at lengths up to 3000mm, 300mm at lengths from 3000mm 6600mm (excluding 4500mm).


6

213

For 70mm Cavity50mm Cavity

100-115mm Inner Leaf125-140mm Inner Leaf

For 90mm Cavity70mm Cavity

100-115mm Inner Leaf125-140mm Inner Leaf

Timber Frame LintelsThe Catnic lintel range for use in timber frameconstruction consists of single and double elementlintels with a sloping outer face and Duplex corrosionprotection which together provide a built-in DPC.


Catnic Timber Frame LintelsDuplex corrosion protection

Ensures optimum durability.

Restraint clips

Allows vertical differential movement of timber frame.

Accessories



Isometric view of a typical application showing lintel over window.

Lintel code Length (mm) Clip fixings

CTF5 750-3600 50mm x 3.35mm diam. plain headgalvanised nails

CTF5 3900-4800 38mm x No10 RD/HD sherardisedwood screws

CN23 Up to 4800 38mm x No10 RD/HD sherardisedwood screws

Length (mm) Number of clips

Up to 1800 3

1950-3000 5

3300-4200 7

4575-4800 9

Lintel restraint clips installation detailsLintels for timber frame construction are supplied

with lintel restraint clips (free of charge), which must

be screw or nail fixed to the timber frame, as shown

here, to allow for differential movement between the

timber structure and the brick facing.

Note: lintels should be suitably propped during construction in accordance with NHBC

guidelines.

Screw fixing

Nail fixingScrew or nail fixings(refer to table for usage)

Clearance

Clearance

Overall lintel length

300max

600max

600max

300max

Centre of lintel

Position of lintel restraint clips



Cavity Walls

CTF5


SWL (kN) 4 5 7 7 9 10

Weight (kg/m) 3.8 4.8 5.6 7.2 8.0 9.0


Ixx (cm4) 82.0 102.8 260.7 332.4 533.7 823.8

Zxx (cm3) 9.4 11.6 21.5 27.5 38.1 51.5


For 102 Outer Leaf 50-60mm Cavity

95 47 95 38

h

CTF5 CN23

h

CTF5 Lintel CN23 Lintel

For 102 Outer Leaf 35-60mm Cavity

Standard lengths are available in increments of 150mm at lengths up to 3000mm, 300mm at lengths from 3000mm 6600mm (excluding 4500mm).


CN23B CN23C


SWL (kN) 10 10

Weight (kg/m) 12.8 16.3


Ixx (cm4) 1210 1521

Zxx (cm3) 70 89

Serviceability moment (kNm) 11 14

External Solid Wall LintelsThe Catnic lintel for external solid walls comes in threeforms, a single element lintel designed to carry asingle leaf of brickwork, a two-piece lintel shaped tocarry the two separate leaves of a 215mm fairfacebrick wall and a box profile with a toe for use in solidbrick or block walls 200mm to 215mm thick.


External Solid Wall LintelsIntegral insulation

Maximising thermal efficiency.

Staggered slots

Minimises cold bridging.


Ensuring optimum durability.

Integral plaster key

Ensures excellent plaster adhesion and safety on site.

Savings on brickwork and insulation

Due to box profile savings can be made.

Box section

Resists twisting during construction.

Instant full load use

Profile is designed to carry full load of wet masonry

as soon as it is installed.

Isometric view of a typical application showing lintel profile in externalsolid wall.



External Solid Wall Lintels

For 200 & 215mm Exterior Solid Walls

CN81B CN81C


SWL (kN) 29 54 47 39 29 26

Weight (kg/m) 15.1 18.5 18.5 18.5 18.5 18.5


Ixx (cm4) 1309 1601 1601 1601 1601 1601

Zxx (cm3) 107 134 134 134 134 134


95 100

CN71 & CN81

h

CN81 Lintel External Solid Wall CN71 Lintel

CN71A CN71C


SWL (kN) 29 27 20 49 44 37

Weight (kg/m) 9.3 9.3 9.3 14.6 14.6 14.6


Ixx (cm4) 378 378 378 593 593 593

Zxx (cm3) 46 46 46 75 75 75




External Solid Wall Lintels

CN48C CN49C


SWL (kN) 15 20

Weight (kg/m) 7.5 9.3


Ixx (cm4) 355 898

Zxx (cm3) 40 70


CNZ94A CNZ94C CNZ95C CNZ96C CNZ97C

Standard lengths (mm) 600-750 900-1500 1650-2100 2250-2400 2550-2700

SWL (kN) 8 5 7 10 15

Weight (kg/m) 2.7 4.4 5.4 6.3 7.5


Ixx (cm4) 27.4 44 123 239 476

Zxx (cm3) 4.1 7.0 13.0 21.0 34.0


CN50C CN51C


SWL (kN) 10 12

Weight (kg/m) 9.0 12.7


Ixx (cm4) 95 476

Zxx (cm3) 14 43


For 102 & 215mm Exterior Solid Walls 18291100

55

hhh

CN50 & CN51CNZ94, CNZ95,CNZ96 & CNZ97

CN48 & CN49

Lintels CN48 and CN49 should be suitably propped and laterally restrained during construction in accordance with NHBC guidelines.

To achieve loading figures, lintels must be constructed with brickwork (blockwork) fully built-in as shown.

Lintels CNZ94, CNZ95, CNZ96 and CNZ97 should be suitably propped and laterally restrained during construction in accordance with NHBC guidelines.

Profile CNZ94A is designed for use over meter boxes only.

CN48 Lintel

CN51 LintelCNZ96 LintelStandard lengths are availble in increments of 150mm.

Internal Solid Wall LintelsCatnic lintels for internal partitions and loadbearingwalls are available in either corrugated, channel or box section depending on load and opening.


Internal Solid Wall LintelsTypical Applications

CN92 & CN102

Suitable for nominal domestic loading

CN100

As above plus:

Suitable for masonry and timber floor loads

Note: 1800 and 2100mm lengths are not suitable

for floor loads

CN5X & CN6X

As above plus:

Universal application caters for all loading

conditions

Direct floor or roof load

Supports concrete floor loads

Supports point loads eg. steel beams, etc.

Optional 4 course profile for high loads at extended

lengths

CN56X & CN66X

As above plus:

Suitable for 140mm and 150mm blockwork


Isometric view of a typical application showing box profile lintel in100mm wall.

NOTE: Whilst the above information is intended to offer general guidance regarding typical applications, it should not be considered ascomprehensive. Requirement not fully covered by the above should be referred to our technical services department for individual consideration.

Corrugated and channel lintels

Offer a cost effective solution for lightweight and

standard duty loads. Use corrugated galvanised steel

lintels for lightweight structures and channel section

lintels for light loadings, made from galvanised steel

with additional polyester powder coating.

Box profiles

Sized to suit brick or block course heights. Use box

profiles for heavier loads and wider openings,

manufactured from galvanised steel with additional

polyester powder coating.



Plaster/mortar keys

Incorporated in all lintels.

CN92 Lintel CN100 LintelCN102 Lintel


Internal Solid Wall Lintels

CN92

Standard lengths (mm) 1050-1200

SWL (kN) 7

Weight (kg/m) 1.2

For 75 & 100mm Interior Solid Walls

For 100mm Interior Solid Walls

CN5XA CN5XC


SWL (kN) 29 25 20 49 39 29

Weight (kg/m) 7.6 7.6 7.6 12.3 12.3 12.3


Ixx (cm4) 277 277 277 452 452 452

Zxx (cm3) 39 39 39 59 59 59

Serviceability (kNm) 6.3 6.3 6.3 9.6 9.6 9.6

CN6XB CN6XC


SWL (kN) 29 49 39 34 29 26

Weight (kg/m) 12.4 15.7 15.7 15.7 15.7 15.7


Ixx (cm4) 904 1159 1159 1159 1159 1159

Zxx (cm3) 78 100 100 100 100 100


75

68 98

25

CN92 CN102

25

100

CN5X & CN6X

100

h

For 100mm Interior Solid Walls

CN100

Standard lengths (mm) 1050-1200 1350-1500 1800-2100*

SWL (kN) 10 13 3

Weight (kg/m) 4.7 5.9 4.7


CN102

Standard lengths (mm) 1050-1200

SWL (kN) 7

Weight (kg/m) 1.8

103 (inside)

h

CN100



Note: When using CN92 and CN102 lintels normal buildingpractice should be observed, in that one course of blockworkshould be laid on the lintel and the mortar allowed to hardenfor at least 24 hours before additional loads are applied.

*Not suitable for floor loads

Internal Solid Wall Lintels

For 140-150mm Interior Solid Walls

CN56XA CN56XC

Standard lengths (mm) 1050-1500 1650-2700 1050-1500 1650-2100 2250-2700

SWL (kN) 29 20 49 44 37

Weight (kg/m) 9.0 9.0 14.5 14.5 14.5


Ixx (cm4) 303 303 565 565 565

Zxx (cm3) 43 43 73 73 73

Serviceability (kNm) 6.9 6.9 11.9 11.9 11.9

CN66XB CN66XC


SWL (kN) 29 54 47 39 29 26

Weight (kg/m) 14.1 18.0 18.0 18.0 18.0 18.0


Ixx (cm4) 1126 1507 1507 1507 1507 1507

Zxx (cm3) 100 127 127 127 127 127



CN56X Lintel over door opening CN5X Lintel supporting first floor partition

CN56X & CN66X

140

h nominalheight (seetables below)

Feature LintelsSpecial lintels for design features such as arches andother non-standard applications, can be designed byour Technical Services Department, working closelywith designers and specifiers.


Feature LintelsLintel features

Catnic standard arch lintels are fabricated quickly and

economically by a unique specialised production

facility, and can be delivered to site along with the

standard lintels, thus avoiding delays to the

construction programme.


Isometric view of a typical application showing semi-circular arched lintelin facing brickwork.

245

150

150

150

Clear Span

Lintel Type Clear Span (mm) Weight (kg)

CCA/600 600 11.79

CCA/630 630 12.26

CCA/900 900 16.53

CCA/915 915 16.77

CCA/1200 1200 21.37

Application

102102

102115-125

50-8550-65

3

3

20mm maximumoverhang

285

150

150

150

Clear Span

Lintel Type Clear Span (mm) Weight (kg)

CCB/600 600 12.96

CCB/630 630 13.47

CCB/900 900 18.14

CCB/915 915 18.40

CCB/1200 1200 23.43

Standard semi-circular arches available for domestic

housing applications.

For alternative cavity and masonry widths, please

contact our Technical Services Department.

Application

102102

102115-125

60-10050-85

Outer Leaf Inner Leaf

3

3





Outside Outside

Section design required

Dim B

Dim C

Dim C

Traditional cavity wallapplication

Single leaf supportapplication

Typically, end bearings are 200mm

Apex arch

Segmental arch

Semicircular arch with upstands

Semicircular arch

B

C

A

R

Special Arch LintelsLintel features

The following examples illustrate a few more popular

fabricated arch lintels available from Catnic. Whatever

your special lintel requirement, Catnic is able to

provide the technical experience and manufacturing

knowledge.

Cavity wall construction

Outer Leaf

Inner LeafCavity

The illustrations opposite are for guidance only. To

ensure the lintel design meets the application, the

following information will be required:

Dimensions as illustrations opposite

Wall constructions

All plans, sections and elevations (where possible)

NOTE: As part of Catnics ISO 9002 Quality Procedure, manufacture of prefabricated

lintels will not commence without a signed (approved) copy of our drawing(s)

returned to our Technical Services Department.

E

E

A

R

E

E

D

E

H

E

B

C

H

H

A

E

B

C

A

EB

C

H


Corner Lintel CU Bay Window Lintel CU

Special Corner or Bay LintelsLintel features

Indicated below are examples of the more popular

mitred lintels available from Catnic. Whatever your

requirement our Technical Services Department will

be able to advise on the best possible solution.

The above illustrations are for guidance only.

To ensure the lintel design meets the application,

the following information will be required:

Clear opening dimensions

Wall constructions

All plans, sections and elevations (where possible)

Plaster key requirements (internal and external)

NOTE: As part of Catnics ISO 9002 Quality Procedure, manufacture of prefabricated

lintels will not commence without a signed (approved) copy of our drawing(s)

returned to our Technical Services Department.

Splayed Bay Lintel CU

Curved Lintel


AccessoriesA range of accessories including ArchCentres, Stop Ends, Cavity Weep Vents and Soffit Cladding to complement your specific lintel requirements.

Lintel ArchCentres Type ACFor the construction of segmental arches in brickwork.

A vacuum formed arch unit for use over openings in external

cavity walls traditional and timber frame providing

permanent centering for brick arch construction.

Made under licence British Patent No. 2063953.

Allows easy construction of segmental arches

Includes integral weep vent

Includes a full-fill insulation core for strength and rigidity

The only Archformer to comply to NHBC with integral

weep vents

Material

Vacuum formed from gloss white ASA (Acrylic Styrene

Acrylontride) with a high density polystyrene core. The

underside of the ArchCentre has self-adhesive pads fitted for

ease of installation and incorporates a minimum of 2 built-in

weep vents. For longer length spans additional weep vents are

included, at maximum spacings of 900mm.

Important note

If used with Catnic soffit cladding, the straight ends of the

ArchCentre (see cross-hatching on illustration, left), which

extend beyond the structural opening, should be removed

before proceeding to stage vi. This operation can also be

carried out to avoid exposing the drip edge of the ArchCentre

within the mortar joint at the bearing end. Cutting into the main

body of the ArchCentre should not be carried out.

Installation notes

i) Do not use damaged ArchCentres, refer to ArchCentre

Installation Leaflet.

ii) Ensure the lintel is adequately bedded-in at supports, and

is parallel to the wall face.

iii) Ensure the ArchCentre and lintel mounting surfaces are

clean and dry.

iv) Check that the ArchCentre is correct for application

(Refer to the code identification on the underside of

the arch unit, and to the lintel specification).

v) Remove the ArchCentre from its protective wrapping.

vi) Locate the unit centrally over the opening to determine

the position on the lintel. The front drip section should

be trimmed off at the bearing end to allow for thin mortar

joints and to enhance the appearance.

vii) Remove the backing from the self-adhesive tape and locate

the unit against the toe of the lintel at a position previously

determined, and rotate onto the lintel.

viii) Apply downward pressure to ensure full contact of the self-

adhesive tape.

ArchCentre Span

ArchCentre Length37.5mm

Isometric view of Lintel ArchCentre

ArchCentre ArchCentre StructuralCode Span (mm) Opening (mm) Rise (mm) CAD Code

ACA0475 475 450-500 75 ACA0475ACA0625 625 600-650 75 ACA0625ACA0925 925 900-950 75 ACA0925ACA1050 1050 1025-1075 75 ACA1050ACA1225 1225 1200-1250 75 ACA1225ACA1350 1350 1325-1375 75 ACA1350ACA1485 1485 1460-1510 75 ACA1485ACA1625 1625 1600-1650 75 ACA1625ACA1700 1700 1675-1725 75 ACA1700ACA1785 1785 1760-1810 75 ACA1785ACB1975 1975 1950-2000 150 ACB1975ACB2125 2125 2100-2150 150 ACB2125ACA2250 2250 2225-2275 75 ACA2250ACB2325 2325 2300-2350 150 ACB2325ACB2425 2425 2400-2450 150 ACB2425

Note

Special ArchCentres available - for details please call our Technical

Services Department on 029 2033 7900

ACA - 75mmACB - 150mm

ArchCentre Span

37.5mm

ArchCentre Length



Lintel Stop Ends Type CL3and C90For eliminating problems associated

with moisture penetration.

Wind-driven rain that penetrates the

external skin of a cavity wall will, under

normal conditions, discharge off the

ends of conventional lintels. However,

with full fill cavity insulation, and in areas

of severe exposure, large volumes of

water can be released from lintel ends

into and through insulation, creating

dampness at internal reveals. Catnic

Stop Ends prevent this problem.

Use CL3 Stop Ends (see Figure 1) for

lintels with a fully inclined face within

the cavity.

Use C90 Stop Ends (see Figure 2) for all

lintels with a 90 brickwork/blockwork

support flange.

Technical requirements

NHBC Standards: Where fair faced

masonry is supported by lintels: cavity

trays or combined lintels should have

Stop Ends.

Zurich Municipal: To prevent water

running into the adjacent cavity, cavity

trays should have 75mm deep Stop Ends

located to coincide with the perpend

nearest to the end of the cavity tray.

Material

Durrpolyethylene 6/A for type CL3.

BS polypropylene for type C90.

Installation notes

i) Ensure the lintel surface is clean and

dry.

ii) Remove the protective covering to

the length of the anchoring strip on

the bottom of the Stop Ends.

iii) Position to suit the perpendicular

joint nearest the lintel ends, ensuring

that the base and back of the Stop

End fit snugly into the front upstand

of the lintel face.

Important note

Cavity weep holes should be provided

over all lintels fitted with Stop Ends.

Stop Ends type CL3 can be applied

to lintels designed for cavity wall

construction with a maximum 100mm

cavity, although they will suit cavities

up to 150mm wide, providing the lintel

upstand rises to 225mm.

Cavity Weep Vents Type WVFor ensuring removal of water from

cavities.

DPC and cavity tray installations over

openings require weeps to discharge

collected water from the cavity above.

Cavity Weep Vents also assist in draining

interstitial condensation, which can

contribute to moisture tracking across the

cavity. The design of Cavity Weep Vents

type WV also provides an aesthetically

pleasing solution, as the front face of the

Weep Vent blends unobtrusively into the

masonry (see figure 3).

Technical requirements

NHBC Standards 1995: Where fair faced

masonry is supported by lintels: weep

holes should be provided at maximum

450mm intervals. Each opening should

have at least two weep holes.

Zurich Municipal: In localities of

moderate exposure or worse, or where

full cavity fill is used, cavity trays should

be adequately drained through weep

holes spaced at no more than 1 metre

apart, with at least 2 per opening.

Material

BS Polypropylene in grey and beige,

to match mortar.

Important note

Cavity weep holes should be provided

over all lintels fitted with stop ends.

Installation notes

i) Position in the perpendicular brick

joints directly above the lintel.

ii) Use a minimum of 2 per lintel at

450mm maximum centres.

Lintel Soffit Cladding TypeRC and FCFor improved appearance

An optional cladding, particularly suitable

for use with PVC-U windows. The

cladding was originally designed to give

a more aesthetically pleasing appearance

to rebated combined box lintels (see

Figure 4). These advantages have now

been extended to cover all flush soffit

lintels (see Figure 5).

For improved protection

Lintel Soffit Cladding also provides extra

protection, especially in coastal regions,

and in situations where much of the lintel

soffit is exposed.

Material

A PVC-U pre-cut unit, supplied in white

or brown. Special colours are available

on request.

Important note

All external wall lintels fitted with lintel

cladding must be installed with a flexible

damp proof course (DPC) ensuring that

the DPC projects beyond the front face

of the cladding.

Figure 2: LintelStop End typeC90 for use withopen back lintelsand external solidlintels

Figure 1: LintelStop End type CL3 for usewith combinedlintels

Figure 5: LintelSoffit Claddingtype FC

98 mmFigure 4: LintelSoffit Claddingtype RC

108 mm

Figure 3: CavityWeep Vent type WV availablein terracotta,beige and grey


Exposure Approximate windzones driven rain

(litres/m2 per spell)

1 Less than 33

2 33 to less than 56.5

3 56.5 to less than 100

4 100 or more

To satisfy NHBC and Zurich Municipal

technical requirements, Catnic lintels

only require a separate DPC in severe

exposure zones i.e. zones 3 & 4 of the

map and as determined by BS 8104.

beyond the outer face of the cavity closer

and vertical DPC. It should provide drip

protection for the door and window

heads, and cover the ends of the lintel

to ensure moisture is shed clear of the

reveals. For all coastal site applications

where the soffit of the lintel is exposed,

the use of a soffit cladding in conjunction

with a separate DPC is recommended to

improve appearance and extend normal

maintenance periods.

Reproduced from BRE report Thermal

Insulation: avoiding risks by permission

of the Controller of HMSO: Crown

Copyright. Report available from CRC

Ltd 020 7505 6622.

Where to use a separate DPC

Domoch

Inverness

Aberdeen

DundeePerth

DunbarEdinburgh

Stirling

Alston

Ayr

Lerwick

Glasgow

NewcastleCarlisle

Workington

Stranraer

Belfast

Londonderry

Enniskillen DungannonMiddlesborough

WhitbyDarlington

Ripon

York

Hull

Grimsby

Skegness

Norwich

Hebben Bridge

Doncaster

Lincoln

Nottingham

Colwyn Bay

Skelmersdale

ChesterBangor

Bala

ManchesterSheffield

Macclesfield

Stafford

LeicesterShrewsbury

Birmingham

Hay-on-Wye NorthamptonCambridge

Peterborough

Welwyn Garden CityColchesterLuton

LondonStaines

GatwickDover

EastbourneBrightonPoole

Southampton

Aldershot

NewburySwindon

Gloucester

BristolWeston-super-Mare

WatchetTaunton

Barnstaple

SidmouthExeter

Cardiff

Swansea

Brecon

Llanidloes

Llandrindod Wells

NHBC Amendments Oct 1992 require a

separate damp proof protection for all

lintels in Scotland, Northen Ireland, the

Isle of Man and in areas of severe or

very severe exposure to driving rain, as

defined under BS 5628 Part 3. The map

indicates typical exposure categories.

In such cases, a cavity tray/damp proof

protection should provide an impervious

barrier draining water outwards. It

should have an overall minimum upstand

of 140mm, returned to the inner leaf

masonry, and be so shaped that there

is not less than 100mm vertical

protection above a point where mortar

could collect.

Where exposure conditions or local

building regulations demand a separate

DPC, Catnic cavity wall lintels not only

provide additional protection against the

elements but also act as a support and

template for the DPC, making it easier

to install, and with less risk of damage.

The DPC should project at least 25mm

Quality AssuranceTechnical ConformityComplies with the technical

requirements of:

National House-Building Council

(NHBC)

Housing Association Property

Mutual (HAPM), with appropriate

adjustment factors.

Zurich Municipal

British and EuropeanStandardsCatnic lintels are designed to satisfy

BS 5977: Part 2: 1983 and are

manufactured from pre-galvanised

steel in accordance with BS EN

10142: 2000 with or without applied

polyester powder coated finish. The

majority of Catnics lintels are covered

by a BSI Kitemark licence or by British

Board of Agreement Certification.

Catnics excellence is internationally

recognised.

Certificate No. FM 14913BS EN ISO 9002: 1994

BS 5977Licence No. KM07234

CERT

IFIE

D TO BRITISH STANDARD

Lintels Tech Guide 03/02 28/6/02 4:55 pm Page 48


Structural PerformanceThe structural data published in the

loading tables included in this

technical guide, was achieved in

accordance with the requirements

of BS 5977: Part 2. Extensive testing

was undertaken at the following test

houses:

The University of Wales, School

of Engineering

The University of Glamorgan,

Construction Centre

Ceram Building Technology,

Stoke-on-Trent

Safe working loads, as defined by BS

5977: Part 2 for cavity wall lintels refer

to uniform distributed loads applied in

the inner to outer leaf ratios:

1:1 For lintels supporting masonry

only

3:1 For lintels normally carrying

timber floors

5:1 For lintels normally carrying

concrete floors

The CU lintel range refers to uniformly

distributed loads in the ratio of 19:1

when non standard or unusual loading

conditions occur.

A lintel should not exceed a max

vertical deflection of 0.003 x the

effective span (effective span =

distance between centre of bearings)

when subjected to the safe working

load (SWL).

Fire TestsCatnic lintels have been tested in

accordance with the relevant parts of

BS476, Methods of Determination of

the Fire Resistance of Loadbearing

Elements of Construction. Details of

the test results can be found in

TRADA (Timber Research and

Development Association) Nos.

FR254, 275, 659, 863, 1662 and

RF94015 and FROSI (Fire Research

Organisation) No. 5001.

Thermal PerformanceAll Catnic cavity wall lintels contribute

to the thermal integrity of the building

as they are supplied with an insulated

core. The core of the Open Back

style lintels is fully filled with CFC free

insulation to prevent cold voids.

Also, because Catnic cavity wall lintels

are shaped to form a built-in damp

proof course, partial fill cavity

insulation can extend down to the top

of the lintel. This means that the cold

voids normally associated with

separate damp proof courses are

avoided, without the need to install

specially shaped insulation batts

behind the DPC.

To achieve the full benefits of an open

back or combined box lintel in

accordance with the robust details

as referred in the approved

documents: Part L1 and Part L2, the

window frame should be positioned so

that the back face of the frame

overlaps the inner face of the outer

leaf of the cavity wall by

a minimum of 30mm.

The standard range of cavity wall

lintels incorporating perforated base

plates have been designed to

minimise any potential cold bridge

path without compromising its

structural integrity. The unique slotted

base plate design on the underside of

the lintels provides an effective

conductivity not exceeding 30W/mK

which satisfies the requirements of the

approved document to support Part

L1 & L2 2002 edition.

Technical Information

Health and Safety

Handling Storage andDisposal Gloves should be worn to avoid

injury from any sharp edges.

When lifting or carrying,

consideration must be given to the

size and weight of the product.

Processes such as welding,

burning, cutting or grinding can

result in vaporising the metal or

generating airborne particles that

may present additional hazards.

Unless required for immediate use

on site, all products should be

stored in a clean and dry

environment on firm and level

ground.

Do not use damaged goods.

When disposing of any Catnic

products or packaging, due

consideration must be given to the

environmental impact of the method

of disposal.

Control of SubstancesHazardous to HealthRegulations 1994 (COSHH) All products are considered non-

hazardous to health under normal

conditions of use.

All products should be used in accordance with their specific instructions to preventfailure.


Technical SpecificationOpen Back Styles

CG and CGH ranges

The lintels are manufactured from

galvanised steel to BS EN 10142: 2000

(continuously hot-dip zinc coated low

carbon steel sheet and strip for cold

forming: technical delivery conditions)

of grade DX51D & Z275, but with a

minimum yield stress of 250N/mm2.

The lintels are further protected

against corrosion by a black coloured

polyester resin coating applied to all

external surfaces of the lintels. The

lintels are fully insulated with

expanded polystyrene bead of density

18kg/m3 giving a thermal conductivity

of between 0.031W/mK and

0.36W/mK.

CU Range


galvanised steel to BS EN10142: 2000

of grade DX51D+Z275 with a minimum

yield stress of 250N/mm2. The lintels

are further protected against corrosion

by a black coloured polyester resin

coating applied to all external

surfaces of the lintels.

The lintels are fully insulated with

expanded polystyrene board

manufactured in accordance with

BS 3837: Part 1: 1986 (Expanded

polystyrene boards specification

for boards manufactured from

expandable beads). The material is

CFC free and has an ozone depletion

potential (ODP) of zero.

The CU range can also be supplied

with a hot dip galvanised finish after

manufacture to BS EN ISO1461: 1999.

At ordering stage ensure that a suffix

PG is included within the lintel code

reference, ie. CU50/100PG.

To satisfy the corrosion protection

system of BS 5977: Part 2 and NHBC

technical requirements, lintels

galvanised to BSEN ISO1461: 1999

must be installed with a separate

damp proof course.

Combined Box/ExternalSolid Wall/ Internal andTimber Frame Styles

CN and CTF range


galvanised steel to BS 10142: 2000




of grade DX51D & Z275 but with a


The lintels (excluding internal lintels

CN92 and CN102) are further

protected against corrosion by a

polyester resin coating applied to all

external surfaces of the lintel. The

lintels are insulated (where applicable)

with expanded polystyrene board to

BS 3837 Part 1: 1986 (expanded

polystyrene boards specification

for boards manufactured from

expandable beads).

CNZ range


galvanised steel to BS 10142: 2000




of grade DX51D & Z600 but with a


All external lintel cut edges are treated

with a corrosion resistant paint.

Glossary of Technical TermsLintels

A structural member spanning an

opening in a wall.

Clear Span or Clear opening

The clear distance between lintel

supports.

Safe working load (SWL)

The total uniformly distributed load

that the lintel is designed to support,

whilst providing an appropriate safety

factor.

Triangulated masonry load

A load assessed in accordance with

the guidelines of BS 5977 Part 1.

Uniformly distributed load (UDL)

A load that is uniformly spread along

the entire length of the lintel.

Point load

The load applied from a single

member such as a steel beam or

girder truss. It should be spread over

an appropriate area so that the limiting

design values are not exceeded.

Moment of inertia (Ixx)

Represents the moment of inertia or

second moment of area of the lintel

section about a horizontal axis

through the lintel centroid indicating

the stiffness of a lintel under a given

load and indicative of the lintel shape.

The greater the Ixx level, the stiffer the

lintel will be and hence the less a lintel

will deflect.

Deflection ()

Vertical or horizontal displacement of

the lintel due to bending about the

horizontal axis.

Modulus of elasticity (Zxx min)

The section Modulus of the lintel

about a horizontal axis, when

multiplied by the permissible working

stress, the resultant value is the

serviceability moment.

Serviceability reaction

The permissible load at an end

support within the working load

capacity of the lintel webs.

End bearing

The bearing length at lintel supports.

Catnic Technical Enquiry Request Form

From:

Customer (full address):

Post Code:

Tel No:

Fax No:

E-mail:

Date:

Site (full address):

Post Code:

Tel No:

Fax No:

E-mail:

Lintel Requirements(please tick)

Open Back

Can Combined Box be included?

Internals

Meter Boxes

Replace Steelwork

Wall Construction(please infill dimensions)

OUTER CAVITY INNER

Type Width Between Masonry Type Width

Is a separate damp proof course to be installed? Yes No

Special Requirements (eg. send to Site/Merchant etc.)

Please include the following (please tick)

Plans/dimensions Elevations (all) Sections Site Plan (for summary)

Floor carcass timber Floor spans (concrete) Roof carcass (for girder trusses)

Note: It is important for a quick turnaround that ALL boxes are completed correctly by referring to the drawings before sending to ourtechnical department

For more information telephone Technical Services on 029 2033 7900 or alternatively fax your enquiry on 029 2086 0135.

Lintels Tech Guide 03/02 28/6/02 5:11 pm Page 51

Catnic is a Corus Group company. Further information can be found on theCorus website at www.corusgroup.com

Copyright 2002Corus

Design by Seven 029 2037 0960

www.catnic.com

CatnicCorus UK LimitedPontygwindy Industrial EstateCaerphillyCF83 2WJTelephone 029 2033 7900Facsimile 029 2086 3178 C01:40000:UK:03/2002

Documents

Catnic Lintels Design Guide