stewartmilnetimbersystems.com

S i g m a ® i i B u i l d S y S t e m :

S h a p i n gt h eF u t u r eC l o s e d p a n e l s o l u t i o n s

aberdeen

Peregrine House

Mosscroft Avenue,

Westhill Business Park,

Westhill,

Aberdeen AB32 6JQ

Telephone: 01224 747000

Fax: 01224 747499

GlasGow

Kestrel House

3 Kilmartin Place,

Tannochside Business Park,

Uddingston G71 5PH

Telephone: 01698 804804

Fax: 01698 804806

ManChester

Harrier House

2 Lumsdale Road

Cobra Business Park

Trafford Park

Manchester M32 0UT

Telephone: 0161 866 6900

Fax: 0161 866 6976

oxford

Falcon House

Curbridge Business Park,

Downs Road, Witney,

Oxon OX29 7WJ

Telephone: 01865 303900

Fax: 01865 303999

smts@stewartmilne.com

stewart Milne tiMber systeMsT E C H N I C A L d E T A I L s

As part of our product development initiatives and utilising learnings from our Sigma® Home research programme, Stewart Milne Timber Systems has developed the Sigma® II Build System, providing a robust and effective system to achieve high levels of fabric performance.

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A fit and forget approach takes into

consideration the assessment of whole

life cycle costing.

The research and development

undertaken for the development of the

Sigma® II Build System emanated from

a two year research project following the

design and build of the Sigma® home.

It has proven invaluable in developing

the Sigma® II Build System and has

informed our thinking to meet the

needs of our customers and provide

meaningful cost effective solutions.

The key learning outcomes from the

prototype build system, relating to fabric

performance, centred on the following

aspects:

• Fabric -v- Renewable devices• Wall thickness• Air tightness• Thermal bridging and transmittance• Construction detailing• Materials• Skills and supervision• Build process• Cost• Repair, maintenance and longevity

• Ventilation

Our approach has been to focus on

an “easy to build” fabric solution that

provides assured performance and

longevity, without risk of failure or

comeback in the future. This is now

recognised by policy makers as the

first priority in low-zero carbon building

design.

The Sigma® II Build System uses

conventional materials and skills with

an easy to understand approach. The

Sigma® II Build System is finished

with a 50mm air cavity and a range of

standard building finishes externally.

The innovative C-stud technology

can also be applied in party wall

applications. A thinner single skin party

wall will be launched in 2012.

As lead industry partner in the

government backed AIMC4 research

consortium, we have continued to

develop and bring to market the Sigma®

II Build System, focusing on a fabric first

solution for low-zero carbon buildings

Code Level 4 and above.

Meeting fabric energy efficiency standardsThe Sigma® II Build System is a fabric first solution that delivers an affordable, reliable and simple to install Build System, promoting a “Fit and Forget Approach”.

The system is designed to achieve

superior levels of fabric performance,

suitable for projects up to 4 storey,

which are seeking to achieve high

fabric performance levels. The

performance criteria offered is:

• U-value of 0.25 – 0.10 W/m2/k

• Air tightness of

5 – 1.5 m3/h/m2 @ 50 pa

• Thermal bridging of 0.08 – 0.02

• Range of wall widths

• Suitable for 1 to 4 storey buildings

Energy performance levels

Scottish and Southern Energy Code level 6, Slough

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innovation: sigMa® ii build systeMWe began with our Sigma® home, the UK’s first five star near zero carbon home, where over a 12 month period, we commissioned Oxford Brookes University and worked in conjunction with the Energy Saving Trust to undertake an innovative research programme of performance testing, monitoring and occupancy evaluation.

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The aims and objectives of the research

project were to:

• Provide specific assessment of

The Sigma® home’s as built

performance

• Shape the development of a new

build system that would deliver

fabric performance in a cost effective

and reliable manner

• Evaluate user behaviours, interface

with the home, induction and use of

controls

• Evaluate fabric heat loss, thermal

comfort, living environment,

air quality, energy and water

consumption

• Understand how low energy, low

carbon homes meet consumer needs

and expectations

• Inform policy makers and the

industry in general on the

performance of low carbon homes

and new technologies

This research was the first step in the

development of the Sigma® II Build

System and allowed us to develop a

product that could change the way

in which we build in the future. The

results are a build system that delivers

sustainability in a cost effective manner

thus shaping the future of low energy

low carbon homes and buildings

• Multiple performance options

• Improved air tightness

• Reduced thermal bridging

• Conventional materials and skills

• 60 years design life

• Two stud options; Solid and C-Stud

• Green Guide A rated

• Insulation Zero ODP and GWP < 5

• Weather resilient

• Robust Detail compatible

• Psi values modelled

• Service battens pre-fitted

• System approach to detailing

• Simple to finish and clad

• Cost competitive

• Fast build

• Factory quality

• Assured performance

• Reliable and low maintenance

• Built in 30 minute fire protection

option

sigMa® ii build systeM Wall solutions

External wall solutions with excellent air tightness, thermal bridging and U-values, the Sigma® II Build System offers a simple and reliable way to assured fabric performance.

1. 102.5mm brick outer leaf (options using lightweight cladding are available)

2. 50mm partially vented cavity

3. Reflective breather paper (factory fitted)

4. 9mm OSB sheathing (factory fitted)

5a. Solid timber studs (factory fitted)

5b. C-stud (factory fitted)

6. Fire retardant EPS beads bonded into panels (factory fitted)

7. 9mm OSB sheathing (factory fitted)*

8. 25mm service zone strapping (factory fitted)

9. Services (site fitted)

10a. 15mm foil back plasterboard (site fitted) OR

10b. 35m Thermal laminate, consisting of 20mm rigid PU insulation and 15mm plasterboard

solid stud – 89MM, 140MM c-stud – 195MM, 235MM

5

1 1

4 4

5b

10a

10b

10a

10b

3 35a

6 67 7

8 8

2 2

9 9

Notes: *Optional fire protection can be factory fitted All seals factory fitted head and foot panels (factory fitted)

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floor solutions

The Sigma® II Build System offers a range of floor cassette solutions in open, closed and insulated formats. Solutions include pre-fitted insulation, edge wrapped cassettes and pre-formed service holes, which ensure the building fabric performs and is easy to build.

a 18mm chipboard

b 15mm OSB decking

c 220mm – 350mm glasswool or fire retardant bonded EPS insulation

d 220mm – 350mm deep solid timber or engineered I-Beam joists

e 9mm OSB boarding

Note: OSB decking is not required when using pre-finished chipboard clad cassettes.

a 18mm chipboard

b 15mm OSB decking

c 220mm – 350mm deep solid timber or engineered I-Beam joists

d 15mm plain plasterboard

Note: OSB decking is not required when using pre-finished chipboard clad cassettes.

Note: Metal web joists can also be supplied, if desired.

A

B

CD

A

B

CD

E

ground floor t iMber cassettes – closed and pre-insulated

interMediate floor cassettes – open and decked With Wrapped and insulated periMeters

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roof solutions

The Sigma® II Build System offers two roof solutions, to suit the varying needs of individual projects, roof shapes and performance requirements.

The system utilises pre-fabricated roof

trusses, spandrel and gable panels and

verge ladder frames. These come pre

designed, complete with all structural

fixings and bracing requirements. Party

wall spandrel panels can be pre-sheeted

with limited combustible boards.

Where air tightness less than 3 is

specified, we recommend the fitting of an

air tightness membrane to the underside

of the roof trusses, with a batten to the

underside to accommodate services.

The membrane should be taped to

the perimeter wall heads and sealed at

laps and junctions, penetrations should

be limited, but where required, taped

and sealed accordingly. The fitting of

membrane should be sequenced after the

building is weather tight and before first

fix, to allow an interim air tightness test to

be completed, before services installation

if desired.

Where air tightness is greater than 3, the

ceiling plasterboard can act as the air

barrier, with appropriate sealing at edges,

joints and penetrations.

If using roof mounted equipment such

as ventilation systems, access and safe

working decks should be used above the

insulation layer without compromising the

air tightness layer.

Air tightness membranes are normally

supplied and fitted by the contractor.

conventional trussed roof systeM

ceil ing cassette systeM

a Pre fitted weather proof membrane

b 15mm OSB decking

c 220mm – 350mm glasswool or fire retardant bonded EPS insulation

d 220mm – 350mm deep solid timber or engineered I-Beam joists

e 9mm OSB boarding

f 25x38mm service zone battens

g 15mm plain plasterboard

E

GF

A

B

CD

The Sigma® II Build System can offer a

horizontal ceiling cassette system. This is

particularly attractive for:

• Fast completions – show complexes

or build out sites

• Roof mounted equipment –

ventilation systems

• Room in roof – future habitable

conversions subject to structural

design assessment

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party Wall solutions

The Sigma® II Build System offers a zero U-value party wall solution, fully filled with effective edge sealing. This complies with the MIMA (Mineral Insulation Manufacturers Association), Design Guidance Oct 2010, in association with RD Ltd and UKTFA.

The system utilises RD Ltd. E-WT-1 and

E-WT-2 solutions with fibre batts between

the party wall frames and floor zones,

which can be fitted as part of the system

erection. The sequence of erection allows

for one leaf to be installed, with or without

sheathing, insulation batts fitted and then

the second leaf erected, to complete the

process.

The use of insulated flexy fire barriers both

sides and between the timber frame party

wall ends, is sufficient to achieve effective

edge sealing. Where required the system

provides sheathing for racking strength

and secure by design compliance, ideally

to one leaf only of the party wall.

Where air tightness less than 3 is

specified, we recommend the fitting of an

air tightness membrane to the face of the

studwork, after acoustic insulation is fitted

and before plaster boarding is installed.

The membrane should be taped to the

perimeter wall heads and sealed at laps,

ends and junctions, penetrations should

be limited, but where required, taped and

sealed accordingly. It is recommended

where heavily serviced walls occur i.e.

kitchens, that an additional service batten

and plasterboard layer is fitted to provide

a service zone with the party wall intact

behind. The fitting of the membrane

should be sequenced after the building

is weather tight and before first fix, to

allow an interim air tightness test to be

completed, before services installation

if desired. Air tightness membranes

are normally supplied and fitted by the

contractor.

Where air tightness is greater than 3, the

first layer of party wall plasterboard can

act as the air barrier, with appropriate

sealing at edges and joints. Fitting of

plasterboard should be similar to the

sequence required for the air membrane

solution, to allow an interim test to be

completed, if desired.

• C-stud flanking detail is undergoing RD accreditation and has secured Stage 1 candidate detail status.

• This conforms to MIMA design guidance and provides full fill and effective edge sealing.

• Option for OSB sheathing for racking and secure by design can be accommodated.

a Sigma® Build System II C-stud external wall panel

b 50x300mm insulated cavity barrier to end of party wall cavity (fitted by Stewart Milne Timber Systems)

c Air-tight membrane fitted on-site, where air tightness less than 3

d 89mm twin leaf party wall, E-WT-1 or E-WT-2

e 9mm OSB pre-fitted to one leaf of party wall only as required structurally or for secure by design

f 50 – 70mm fibre batt insulation between frames

g 90mm fibre insulation between studs (fitted by contractor)

party Wall to external Wall detail

A

B

C

D

EF

G

Note – 0.15 U-value C-stud systems shown

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other options

We have developed an innovative sliding bracket fixing system in conjunction with our preferred supply chain partners, that allows windows and doors to be installed horizontally within the timber frame aperture, in the factory, stacked as panels and moved to their final position, 50mm proud of the panel face.

This is a very safe operation and omits

manual handling concerns and cost

associated with damage, particularly

relevant for heavy window and door

components.

Windows are supplied with protected

frames and “peel off” glazing protection,

so that windows can still be used during

construction for ventilation and to provide

adequate daylight. In addition, windows

can be factory fitted with air tightness

tapes (generally for solutions requiring

air tightness less than 3), for easy sealing

to the panel aperture reveals, once the

windows are moved to their final position.

Handles, extension sills and vents are

supplied loose for the contractor to fit.

This system is available for u-PVC

windows and external composite GRP

doors ranging from 1.4 – 0.8 U-value,

including triple glazed units. The

maximum size of unit that can be installed

is a French door up to 1.8m x 2.1m and

triple glazed (max 150kg).

Windows and external doors are shipped

in individual sequence to our factory to

suit production runs. This helps reduce

cost and the amount of re-handling.

Timber windows can be fitted, by utilising

timber pinch battens, but are supplied

50mm proud of the panel face, requiring

more care and attention during handling,

transportation and erection.

factory fitted WindoWs and doors

offsite construction

The Sigma® II Build System factory produced components guarantee that a high quality fabric can be simply and speedily assembled on site, with less waste and transportation, than conventional methods.

The build system also offers a range of

offsite construction features, including:

• Closed panel and fully insulated

• Service cavity pre-fitted

• Floor cassettes wrapped, air sealed

and insulated

• Built-in air tightness detailing and

seals

• Safer build system

• Principle service penetrations

pre-formed

• Potential to air test, immediately after

kit erection

• Optional factory fitting of windows

• Optional insulated ground floor

cassettes

• Optional insulated ceiling cassettes

• Optional insulated roof cassettes

The amount of site labour time has also

been reduced through the integration of

several trades/suppliers into one package,

thus eliminating non value adding site

processes, which attract hidden capital

cost and downstream cost overruns.

The simplicity of the system eases the

burden of supervision and material

requisition on site managers allowing

them to focus on quality and safety.

The Sigma® II Build System reduces

many of the health and safety hazards

on site and can be erected without the

need for fall arrest systems and controlled

manual lifts.

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systeM certification

BBA Product Certification:

• Extensive testing programme completed, including fire, thermal and structural

• Build system certification, suite of wall, floor and roof construction details and product sheets

• Site and factory inspected annually

RD Acoustic Flanking Accreditation

• Acoustic field testing successful

• Stage 1 candidate assessment passed

NHBC Warranty

• Multiple schemes successful and warranty issued to developer

• Several site inspections completed

• NHBC accepted

BLP Durability and Maintenance

• 60 year assessment completed

• High durability and virtually

maintenance free

Lloyds Build Offsite, Property Assurance Scheme (Mortgage and Valuation)

• Properties registered on Lloyds database, assist valuation and mortgage applications, beyond typical new build warranty periods

• RICS and Council of Mortgage Lenders backed

• Funded and supported by Santander, Lloyds, RBS and Nationwide

• Lloyds Banking Group, mortgage

letter of comfort available

The Sigma® II Build System is already being used by clients to deliver a more sustainable, energy efficient way of building, safe in the knowledge of having a fully certified and approved system.

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design flexibility durable and strong

A detailed design protocol and library

of construction details are available to

project architects and engineers to allow

them to design buildings and interface

with other building elements such as

foundations and claddings.

Significant structural testing has resulted

in strength properties, approximately

30% greater than conventional open

panel timber frame system, reducing the

need for internal racking and providing

a very robust and durable building

envelope. The C-studs are typically 15%

more stable and stronger than a 140mm

solid timber stud. The EPS insulation

system is highly durable and can easily

accommodate exposure to weather

storms, during storage, transportation

and construction, before the final

weather proof finishes are applied to the

building. Due to the lock joint detailing,

the wall panels have 40% less cross

gain shrinkage than conventional timber

frame walls.

A detailed 60 year durability assessment

was completed by Building Life Plans

(BLP), using a detailed elemental risk

based assessment, commonly used by

many lenders and insurance companies.

This validated the system for a minimum

60 year design life, under normal

maintenance and weathering regimes.

The panels are typically designed to

suit 3.6m x 2.4m high sizes for ease of

transportation, but can be made up to

6m x 3m high. There is no restriction

in the height, shape or configuration of

panels with each individually designed

and made to suit the building layout.

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The Sigma® II Build System has been designed to comply with BS 5268 and EC5, British and European Structural Design Standards, including disproportionate collapse.

building services siMply accoMModated

Principle ductwork for ventilation

systems can be pre-formed in solid

joists, or factory drilled within I-Beams.

This prevents the costly over specifying

of joists to allow flexibility throughout.

Where information is not to hand I-Beam

or metal web cassettes can be provided,

which allows greater flexibility on site.

Where ground floor or ceiling cassettes

are adopted, holes can be pre-formed

with plastic liners to accommodate SVP,

utility risers or ventilation duct drops,

preventing the need for drilling on site.

Within the wall panels, penetrations can

be easily formed on site for such things

as incoming water or gas points, TV

cables and boiler flues. Lengths of pipe

sleeve are provided, to allow a neat hole

to be cut and sleeve inserted, to maintain

the thermal properties of the panel and

finished with a simple air seal internally.

Intumescent fibre pipe sleeves are used

where hot boiler flues pass through the

wall.

13

The Sigma® II Build System has been developed with services integration in mind. The wall panels come pre-fitted with battens which create visible service runs, which can simplify fixing, as well as acting as the support for plasterboard.

a Chipboard flooring/OSB Decking

b 220mm – 350mm deep solid timber or engineered I-Beam joists

c 225x75mm slots pre-formed in I-Beam joists to suit ventilation duct route

d 50mm diameter holes pre-drilled in solid timber or I-Beam joists within pre-determined zones

e Rectangular ducting for ventilation system (site fitted)

f Heating, hot and cold water pipes, and electrical cables through pre-drilled holes (site fitted)

g 15mm plain plasterboard (site fitted)

A

B

CG

DE F

services detail

The improvement in performance ranges

from 10 – 95% over ACD’s. Y-values

have been calculated for a typical three

bedroom semi detached house and

can achieve 0.031, compared to the

Accredited Details, which typically give

performance of around 0.10 – 0.08.

Each 0.01 improvement in Y-value

performance, can yield a 1% benefit in

SAP.

This is achieved by using the inner

sheathing as the primary air barrier, and

offers a membrane free wall solution. Air

tightness features include:

• C rail lock joints at panel head and

foot

• Pre-fitted air sealing gaskets at panel

junctions and corners

• Pre-fitted air membrane, edge

wrapped around external perimeters

of floor cassettes

• Site fitted air sealing foam under

soleplate, installed irrespective of

weather

Choosing the full suite of Sigma® II

Build System product options allows

for an interim air tightness test to be

conducted immediately after kit erection

and before first fix installation. We can

offer guidance on undertaking interim

air tightness testing, where only the

Sigma® II Build System wall panels are

being installed and co-ordination with

other trades or building elements is

required.

therMal bridging better than accredited details (acd’s)

air tightness built in and easily achieved

The Sigma® II Build System, using the C-stud option, offers superior thermal bridging. The system has a ready to use library of construction details, which have been modelled to determine their psi values.

The Sigma® II Build System has been used to construct numerous projects for a variety of clients. The results have shown that the system achieves air tightness as low as 1.5.

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Typical Sigma® II Build System Psi value certificate

air tightness extra options

• Factory fitted windows and doors, complete with pre-fitted air sealing tape

• Ceiling cassette, closed and insulated

• Site fitted air membranes, to roof and party walls, installed after building is watertight

• Pre-formed primary service holes, with optional air grommet sealing patch

teMperature factor3 for huMidity and Mould

ƒ = 0.906

linear therMal transMittance W/m.k

C = 0.045

teMperature distribution[°C]

20

10

0

15

The Sigma® II Build System uses a simple approach, with no membranes or tapes, required to achieve performance. This reduces the site management required to supervise and co-ordinate materials fitted on site, ensuring the focus of site delivery remains on health and safety and quality.

This approach builds in assured performance in a more reliable and predictable way. This is likely to become more topical in future building regulations.

An assessment of costs compared to other build methods demonstrates the cost savings made when using the Sigma® II Build System.

• Sigma® II Build System is cheaper, for the wall element

• Faster and more predictable to build, due to pre-fabrication

• More reliable to build, with less supervision

• Less prone to workmanship and weather related quality problems

• Less prone to unforeseen cost over-runs

Additional cost savings can be made in:

• Waste removal

• Services installation

• Scaffolding

• Site supervision

cost benchMarking hassle free and cost efficient

The Sigma® II Build System offers a lower cost solution to conventional methods of construction, for high performance fabric solutions, where insulation and other components are site fitted and attention to detail is paramount.

Through our involvement within the

AIMC4 consortium, Stewart Milne Group

has built a terrace of 3 homes in 8

weeks, using the full range of Sigma®

II Build System options. These were

designed to meet Code for Sustainable

Homes Level 4 through a fabric first

solution, without renewable devices.

Typical construction durations for other

methods, based on a high performance

fabric, would be:

• Masonry – 18 weeks

• Sigma® II Build System – 8 weeks

(with full range of options)

The Sigma® II Build System shortens the

cash cycle, from commitment of cost to

receipt of revenue. Another benefit of

the system is the savings in prelim and

finances charges, as a result of build

speed.

Typical preliminary and finance charges

on a cost per week basis are:

• Prelim costs £4,200 per week#

• Development interest charges £346 per week*

Commercial benefit, based on terrace of

3 unit example:

• Sigma® II Build System saves

£45,460 over masonry

speed of build fast and predictable delivery

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Using the Sigma® II Build System reduces site prelim costs, improves predictability and reduces finance charges. The result is a reduction in the cash cycle and fast completion of projects.

#Based on typical private development site of 150 units *Based on typical all in cost for terrace of 3 units, is £360K @ 5% annual interest charge

exaMple build prograMMe benefit

In simple terms, for a project

of 10 terraced blocks, you save

£45,460 or 10 weeks in time over

masonry. This excludes the benefits

of simplifying the build, reducing

risk and achieving assured fabric

performance.

exaMple build prograMMe (10 blocks of 3 terraces)

Mas

onry

bui

ld

Week 1

1 x

site

Man

ager

Week 2

Week 3

Week 4

Week 5

Week 6

Week 7

Week 8

Week 9Week 10

1 x per Week 18 Week

28 Week build period

sigM

a ii

bui

ld s

yste

M Week 1

1 x

site

Man

ager

Week 2 55% QuickerWeek 3Week 4 10 Weeks lessWeek 5

Week 6 £45,460 savingWeek 7Week 8 cash floW benefitsWeek 9

Week 101 x per Week 8 Week

18 Week build period

17

The adoption of a high performance fabric solution cannot be undertaken in isolation, without considering ventilation and solar gain, within the building’s design.

Our Sigma® research has yielded

significant data and learning, around the

ventilation and solar gain design options,

to ensure that the thermal comfort and air

quality within the home is in keeping with

home owner’s expectations.

The correlation between high

performance fabric solutions, ventilation

and solar gain needs to be considered

at concept design stage, through the

development of the design and during

the construction process. This is likely to

become an integral part of future building

design for all forms of construction.

We have experienced design personnel

who can provide advice on areas for

design consideration and offer appropriate

solutions.

therMal coMfort keeping cool, staying WarM

designOur team of 25 designers are the best

in our industry with unrivalled expertise,

knowledge and experience. We have our

own structural engineers and offer a fast

and efficient process with an up front

design service. Our design co-ordination

team work alongside your project team

to design out cost and improve value

engineering.

Manufacturing capacityAcross our two factories, we have

capacity to manufacture 8,000 units

per annum and the ability to flex our

manpower upwards to accommodate

larger projects and shorter lead times.

Alongside our integrated supply chain

we can comfortably meet customer

requirements across the UK.

trained and coMpetent installersWe have expert teams of skilled and

well trained erect teams. Each erector

goes through training and induction

programmes, before becoming an

approved installer. As part of our ISO QA

procedures, which are regularly audited

to ensure compliance, all our teams are

registered.

As part of the service offered, we

provide the following installation

information:

• Erection method statements

• CDM and risk assessments, including

fire safety where required

• Fixing schedules

• Repair and maintenance guidelines

• Handover and sign off checklists

• Crane lifting and access plans

Foundation tolerances must comply with

NHBC requirements, although care and

attention should be applied to ensure

foundations and slabs are as accurate

as can be, to prevent unwanted packing

or re-building.

18

delivering your project

The Sigma® II Build System builds on the existing expertise and skills within our established sub contractor workforce. The system adopts conventional practise and processes used for open panel timber frame erection, resulting in quick and easy installation.

stewartmilnetimbersystems.com

S i g m a ® i i B u i l d S y S t e m :

S h a p i n gt h eF u t u r eC l o s e d p a n e l s o l u t i o n s

aberdeen

Peregrine House

Mosscroft Avenue,

Westhill Business Park,

Westhill,

Aberdeen AB32 6JQ

Telephone: 01224 747000

Fax: 01224 747499

GlasGow

Kestrel House

3 Kilmartin Place,

Tannochside Business Park,

Uddingston G71 5PH

Telephone: 01698 804804

Fax: 01698 804806

ManChester

Harrier House

2 Lumsdale Road

Cobra Business Park

Trafford Park

Manchester M32 0UT

Telephone: 0161 866 6900

Fax: 0161 866 6976

oxford

Falcon House

Curbridge Business Park,

Downs Road, Witney,

Oxon OX29 7WJ

Telephone: 01865 303900

Fax: 01865 303999

smts@stewartmilne.com

stewart Milne tiMber systeMsT E C H N I C A L d E T A I L s