Superior strength and quality

Energy saving and cost effective

Reduces condensation risk

Enhances thermal performance

Complete airtight solution

AirSmart®

The intelligent choice in airtight systems

The AirSmart® Solution

Air leakage and U-value performance

AirSmart® vapour control layer

AirShield vapour control layer

Accessories

Icopal MonoSleeve

Detailing principles

Roof Window detail

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Contents2 3

Air tightness is absolutely essential if you

want to achieve a healthy environment,

reduce heating costs, eliminate heat

loss and reduce CO2 emissions. It also

protects the building envelope from

harmful condensation in walls and roof

spaces that can form mould, mildew

and rot resulting in the decay of the

construction and potentially leading to

health risks.

The Solution

The AirSmart® solution from Icopal

consists of two specially designed

membranes presenting benefits

depending on the construction

requirement in new build or refurbish-

ment projects. Since air tightness

involves a lot more than just

membranes, Icopal also offer a range

of specially designed accessories for

overlaps, details and upstands including

Monosleeve; a pre-made flexible

collar providing an easy, fast and

airtight solution for electricity cables

and pipe penetrations.

Why air tightness

Air tightness is the control of air leakage

and heat loss through the building fabric

and in particular at interfaces , joints

& junctions It is therefore extremely

important to provide an airtight seal

within the internal building fabric that

eliminates air leakage heat loss and

unwanted condensation in the building

fabric.

Carbon dioxide emissions from the

housing sector accounted for 27 per

cent of the UK’s carbon footprint.

Research shows that poor air tightness

alone is responsible for between

30-40% of the heat loss from buildings.

The UK government is introducing

legislation that will require CO2 levels to

be cut by 60% by 2050 from those levels

recorded in 1990. This will result

in improved U-values in buildings,

however, air leakage issues must

firstly be addressed by the introduction

of an air tightness system such as

AirSmart®.

Air Leakage

Effective Air tightness involves securing

air leakage paths and therefore reducing

the risk of condensation through warm

air from the inside of the building coming

into contact with cold surfaces in roofs

and walls. The amount of moisture

created in a typical domestic dwelling

is approximately 15 litres of water per

24 hours. If not ventilated away, the

moist air will enter the building fabric

and take with it heat that will eventually

condense. In winter time this will often

accumulate on the roofing underlay

including roofs designed with vapour

permeable membranes where the

amount of condensation is higher than

the membrane capacity. In severe cold

weather and if a building is newly built or

even up to 12 months after construction,

condensation will be a major concern.

The AirSmart® system controls the

amount of vapour that can escape into

the building fabric making it possible

for vapour permeable membranes to

perform as designed even in winter

conditions.

Given a winter situation where outside

air temperature is 5°C at 90% relative

humidity (RH) then it would take

approximately 10 m3 of air change to

remove 1 m3 of the moist indoor air at

20°C at 50% relative humidity. This is

not always possible as periods of cold

weather often provide very little air

movement resulting in the formation

of condensation. The moment vapour

condensates it will change from being

airborne to becoming liquid and can

therefore no longer pass through the

vapour permeable membrane. This in

turn means that the condensate water

will drip down onto the insulation and

affect the insulation’s U-value and may

subsequently form mould, mildew and

rot within the construction.

Due to these factors there is a much

higher focus on building airtight, and

ensuring a comfortable indoor climate.

Building airtight also means it is essential

to have adequate air changes withiin

the building as stated within Part F of

the Building Regulations. In essence

it is about the combination of building

airtight and ventilating correctly.

The AirSmart® Solution

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The smallest crack in a plasterboard

or unsealed overlap in a vapour control

layer, which is unavoidable using

traditional building techniques, will lead

to what is referred to as ‘convection’.

A small 1mm wide gap over an area of

1m2 in the inner building fabric like the

plaster board will lead to a reduced

U-value. It is important that reliance on

workmanship and cross over trades are

reduced as research shows that in cold

winter conditions the difference between

a perfectly sealed vapour control layer

system and a small 1mm continuous

gap in an area of 1m2 can reduce the

U-value performance by a factor of 4.8.

This means that the U-value cannot

be achieved if the structure is not

airtight and therefore you would require

increased energy to heat the house. It is

important to remember that air tightness

doesn’t increase U-value, however it

does provide the perfect conditions for

the intended calculated U-value to be

achieved.

Common air leakage path

There are a vast number of possible air

leakage paths in a building which need

to be considered for Airtight design

such as:

• Gaps around windows and external

door frames.

• Areas around extractor fans, cooker

hoods and boiler flues.

• Gaps around electrical services,

sockets, light fittings, built-in spot

lights, antenna cables.

• Partition junctions such as ceilings or

external walls.

• Holes through walls such as gaps in

the mortar joints or missing joints on

the inner leaf block work.

• Cracks in plaster board.

• Cuts and holes in the vapour control

layer for service penetrations.

• Gaps around loft hatch frames or the

seal between the hatch and frame.

• Gaps around central heating and soil

pipes, plumbing pipes behind sinks,

baths and toilets.

Air leakage and U-value performance

Air tightness – Building Regulations

The Building Regulations approved

document Part L1A 2010 now

specify that any new dwellings are built

airtight. The regulation is focused upon

conservation of fuel and power usage.

Part L1A states that any new dwellings

are tested for air tightness in accordance

with Table 1 as shown.

The Scottish Building Regulations,

Section 6, states the requirement to

build an airtight building and all new build

domestic dwellings should be should be

tested for air tightness (see Table 2).

Air tightness testing is carried out by

using a method known as a ‘blower door

test’ in accordance with BS EN 13829.

The measurement is taken by blowing

air into the house via a particular door

that is mounted in the main entrance.

By the use of thermographic equipment,

leakage paths can be identified.

The new Part L1A requires an air

tightness of maximum 10 m3/hr/m2 air

loss at a pressure of 50 Pa. Standard

good practice for air tightness testing in

the UK is a maximum of 7 m3/hr/m2 and

best practice is 3 m3/hr/m2 of air loss.

Section 6 of The Scottish Building

Regulation requires a maximum of 7

m3/hr/m2 of air loss at a pressure of 50

Pa. The Scottish regulations will be fully

enforced for all dwellings by 1st October

2011 and this test is mandatory.

Number of instances of the dwelling type

Number of tests to be carried out on the dwelling type

4 or less Two tests of each dwelling type.

Greater than 4, but equal to or less than 40

Three tests of each dwelling type.

More than 40 At least 10% of the dwelling type, unless the first 5 units of the type that are tested achieve the desired air permeability, when the sampling frequency can be subsequently reduced by 2%.

Number of pressure tests for dwellings that have not adopted accredited construction details

Pressure test frequency

Dwelling description

Baseline Testing of completed dwellings to be carried out on 1 in 20 dwellings or part thereof.

Large developments

It is advisable to test more than one example of the same dwelling type, completed at different stages in the overall development, to help establish consistency in quality of construction.

Smaller developments

The proportion of dwellings tested may need to increase, dependant on the range or type and form of dwellings present, to ensure a representative sample is taken.

One single dwelling

Air tightness testing should be carried out as it will not be possible to obtain comparative data on the quality of construction from similar dwellings. Alterna-tively, where a default design value of 15 m3/hr/m2 at 50 Pa is stated in demonstrating compliance under standard 6.1, testing need not be carried out.

50 Pa

England/WalesMax. 10m3/hr/m2

ScotlandMax. 7m3/hr/m2

Crack

Part L1A Regulations Scottish Building Regulations

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Tabel 1

Tabel 2

AirSmart® is a high-performing, multi-

purpose air barrier and vapour break

containing a special co-polymer coated,

spun bond, non-woven reinforcement. It

is designed to provide both an effective

air leakage barrier as well as regulating

vapour control properties.

Condensation

Typically, many damages to buildings are

caused by moisture from condensation

and moist building materials used within

a new construction. It is therefore of

vital importance that any moisture that

penetrates into the building envelope

(diffusion) or residual moisture from

the construction phase can dry out

effectively. The AirSmart® membrane

provides this protection due to its

low, but dynamic regulating vapour

resistance and can be used in new build

as well as in refurbishment projects as a

retrofit membrane.

Mechanical performance

The membrane has a reinforced

structure making it extremely durable

during installation and can easily be

shaped without stretching or tearing

around fixing points. The dynamic

performance of the membrane also

means it can be used with ecologically-

friendly insulation such as sheep’s wool,

which is sensitive to moisture build up

and can affect the thermal performance

of the insulation.

Dynamic performance

In the Winter period the dynamic

performance of the AirSmart®

membrane will allow a controlled

amount of vapour through the building

envelope which can be ventilated away

through the permeable roof underlay

without overloading the membrane and

causing unnecessary condensation risk.

In the Summer period the dynamic

performance of the AirSmart®

membrane is reversed as the vapour

drive is from outside to indside. In this

situation the membrane will allow a

AirSmart® vapour control layer

controlled amount of vapour to pass

into the building which is ventilated away

by natural ventilation. The AirSmart®

membrane will provide this protection

whilst remaining completely airtight

once installed using the entire AirSmart®

accessory program to effectively seal

the membrane.

The AirSmart® membrane is installed

on the warm side of the insulation,

where it can block air leakage and

help meet the building regulations and

standards. It thereby improves the

thermal performance of the insulation by

reducing convection flow.

Testing

The AirSmart® membrane is tested and

approved as a vapour barrier under the

European CE marking regulations and

classified as a Type A membrane under

the EN 13984 standard.

Benefits

• Superior strength for secure

installation and detailing.

• Due to the dynamic effect of the

product, any residue moisture can dry

out minimising the risk of unhealthy

mould and mildew.

• Energy and cost effective by reducing

convection flow therefore improving

the thermal performance of insulation.

• Lightweight and easy to cut and

handle.

• When fixed to the underside of

timber rafters provides a solid and

secure support for non rigid insulation

products.

Technical data

Performance Unit Value

Weight g/m2 130

Roll size m 1.5 x 50

MD CD

Tensile strength N/50 mm >400 >400

Nail tear resistance

N >250 >250

Water vapour resistance

MN s/g 5 - 20

Fire retardant class

E

MD: Machine DirectionCD: Cross Direction

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The AirShield membrane is a high

performing vapour control layer

and effective air barrier. Its robust

composition and reflective surface

enhances the overall thermal

performance of walls, ceilings and

floors. AirShield contains a highly

reflective foil with a high strength

polyester reinforcement sandwiched

between polyethylene for strength and

superior water vapour resistance.

Versatile

In addition to the superior vapour

control performance over any standard

800 gauge polyethylene films, the

highly reflective and low emissivity foil

face also contributes to the thermal

enhancement of the structure once

installed with the reflective surface

facing towards a still-air cavity. This

means not only does AirShield help

to maintain the calculated U-value

by limiting convection it can also help

contribute to the structure’s U-value.

Testing

AirShield is approved and tested as a

vapour barrier under the European CE

marking and is classified as a Type A

membrane in the EN 13984 standard.

Benefits

• Superior strength yet enables easier

installation and detailing.

• Improved thermal performance saving

costs and energy.

• Energy and cost effective by improving

the thermal performance of insulation

by reducing convection flow.

• Reflective, corrosion-resistant surface

that increases performance

throughout the lifetime of the product.

• Excellent vapour resistance helps

avoid condensation risk, ensuring a

safe and sound structure.

AirShield vapour control layer

Technical data

Performance Unit Value

Weight g/m2 190

Roll size m 1.5 x 50

MD CD

Tensile strength

N/50 mm >400 >425

Nail tear resistance

N >180 >185

Water vapour resistance

MN s/g >1000

Reflection % >75

MD: Machine DirectionCD: Cross Direction

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The AirSmart® accessory range has

been developed specially for the

AirSmart® membranes helping to

reduce uncontrolled air and vapour

leakage, whilst ensuring durability.

AirSmart® Lap Tape

Single sided green PE film with a strong

reinforcing grid and water based acrylic

adhesive with a release paper backing.

AirSmart® Lap Tape is highly suitable for

laps, butt joints and straight detailing.

Dimensions: 60 mm x 25 m.

AirSmart® Detail Tape

Single sided green PE film with split

release paper and a water based

acrylic adhesive. The tape has a special

diagonal reinforcing grid making it

possible to carry out detailing work

around penetrations without stretching.

AirSmart® Detail Tape is highly suitable

for detailing at windows and door

frames as well as around large pipe

penetrations.

Dimensions: 60 mm x 25 m.

AirSmart® Metalised Tape

Single sided acrylic adhesive with a

reflective foil facing. Should be used as

lap and butt joint tape together with the

AirShield membrane.

Dimensions: 50 mm x 25 m.

Monobond LT

Double sided adhesive butyl tape

based upon light and highly age

resistant rubber. The tape is used for

the sealing of AirSmart® membranes

against penetrations, corners and wall,

ceiling and floor joints as well as

between membrane and building

elements

Dimensions: 30 mm x 10 mm x 30 m.

AccessoriesAirSmart® Sealant

AirSmart® Sealant is water based and

specially developed for the sealing of

joints between AirSmart® membranes

and building materials such as bricks,

wood, plaster and concrete.

The sealant is applied to one surface in

an 8mm thick bead.

Packaging: 300 ml tube.

Coverage: Approx. 7m.

AirSmart® tapes and sealant for the AirSmart® system

AirSmart® Lap Tape

AirSmart® Detail Tape

AirSmart® Metalised Tape

Monobond LT

AirSmart® Sealant

AirSmart® VCL • • • •

AirShield VCL • • • • •

Tape application

Lap sealing • • •

Butt joints • • •

Details, penetrations • • •

Membrane & wall detail • •

AirSmart® Metalised Tape AirSmart® Detail Tape

AirSmart® Sealant

AirSmart® Lap Tape

Monobond LT

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Icopal MonoSleeve is a five-in-one

sized cable and pipe sleeve accessory

consisting of an EPDM rubber plate

measuring 245 x 245mm with a self

adhesive backing, suitable for cable

and pipes up to Ø180mm.

The MonoSleeve ensures that

penetrations in the AirSmart®

membrane can be made completely

air- tight and avoid weak points in the

system created by cutting for service

penetrations.

Pipe size (in Ø mm)

Pipe size (in Ø mm)

Pre-made substrate size (in Ø mm)

From (mm) To (mm)

16 18 32

41 46 68

65 72 93

90 100 129

135 150 180

Installation instructions

1. Select and cut out the pipe

dimension needed, Remembering

to cut through the backing paper

and ensure the dimension chosen is

10-20% smaller than the actual pipe

size.

Icopal MonoSleeve

2. Pull the Icopal MonoSleeve over

the pipe up against the wall before

removing the split backing paper.

3. Press the MonoSleeve firmly into

place on the underlay ensuring that

a small up-stand forms around the

pipe. For security, a single layer of

Icopal AirSmart® Detail Tape can be

used around the pipe.

4. Installed MonoSleeve

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With MonoSleeve you can make airtight penetrations

of ventilation pipes of up to Ø 180mm.

The AirSmart® system is sealed with Monobond LT

or AirSmart® Sealant to the load bearing beam.

A strip of Xtra Load DPC is placed between the wall

and top rim. The AirSmart® system is then sealed to

the Xtra Load DPC using Monobond LT.

The AirSmart® system is sealed to the brick work

with AirSmart® Sealant or Monobond LT.

Detailing principles Roof Window detail

References

• Building regulations, approved document Part L1A 2010.

• BS 5250:2002: Code of practice for control of condensation in buildings.

• BS EN 13829:2001: Thermal performance of buildings. Determination of air permeability of buildings. Fan pressurization method.

• BS 9250:2007: Code of practice for the design of air tightness of ceilings in pitched roofs.

• The Code for Sustainable Homes (England, Wales).

• BRE IP 4/6 Air tightness of ceilings – energy loss and condensation risk.

• The Code for Sustainable Homes (Scotland), Section 7.

• The Scottish Building Regulations, Section 6.

The AirSmart® Detail Tape is used around windows

between the membrane and window frame to ensure

a perfect airtight seal.

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ICO

2230

Icopal, founded in 1876, operates worldwide and has 35 production

facilities and more than 90 offices in Europe, North America and Asia,

Icopal is Europe’s leading manufacturer of products for the protection and

waterproofing of building constructions, particularly roofing materials and

waterproof membranes.

Inspiration

Motivation

Creation

Icopal Limited Barton Dock Road, Stretford, Manchester M32 0YL ■ Tel +44(0)161 865 4444 ■ Fax +44(0)161 864 2616 ■ Email: info.uk@icopal.com www.icopal.co.uk