If the material that you are considering using offers resistance to airflow and is strong and durable, consider the following installation factors:

• Is it easy to install without help?
• If installed in a concealed location, will it last the life of the building or will it be accessible and easily repairable?
• Is it compatible with other materials in the system? Can it be successfully sealed to adjacent materials?
• Is the choice of material appropriate for any other work being done?
• Does it serve other functions such as acting as insulation, a vapour barrier or part of a drainage plane?

Sheet materials

i) House wrap (typically made from a spun polyolefin plastic)

• is generally used to wrap the exterior of a house
• acts as a wind barrier when installed on the exterior; prevents wind from reducing the nominal RSI value of insulation
• acts solely as an air barrier; does not function as a vapour barrier
• can function as a drainage plane surface when the upper sheet overlaps the lower sheet and the flashings and all edges and penetrations are sealed with acoustical sealant or sheathing tape
• application in wide sheets minimizes the number of seams required
• should be protected from extended exposure to sunlight
• when installed with stucco or embedded in stone veneers, requires an additional 5-mm (3/8-in.) gap for a drainage plane (use a drainage mat) to prevent the stucco from bonding to the house wrap
• should not come in direct contact with cedar because the oils in the wood can cause deterioration in the product

ii) Polyethylene sheeting

• is commonly installed as a vapour barrier in the thickness of 0.15 mm (6 mil) because it is more durable on the construction site
• should be labelled showing that it conforms to the Canadian General Standards Board (CGSB) standard for polyethylene
• application in wide sheets minimizes the number of seams required
• should have the seams and edges supported on both sides to maintain the seal
• requires an appropriate sealant and overlapped joints
• functions as a vapour barrier. Should always be used on the interior or follow the 1/3 - 2/3 rule (see Health and safety considerations). Follow local building codes for placement of a polyethylene vapour barrier.

TECHNICAL NOTE:

If the sheeting will be exposed to sunlight over an extended period during renovations, use a UV-stabilized polyethylene.

iii) Polyamide sheeting

• is also known as Nylon-6 vapour retarder film or smart barrier
• adapts its permeability to the conditions. In cold temperatures, it offers high resistance to vapour pressure; in warmer conditions, it becomes more permeable, allowing the structure to dry out.
• can be installed as a vapour barrier or an air barrier
• should not be used in indoor areas that have high humidity such as an indoor spa or pool or a bathroom

iv) Rigid materials

Most solid building components including drywall, plaster, plywood, glass, wood, rigid foam insulation and poured concrete (not concrete blocks) will act as air barriers. Seal all seams between these materials with the appropriate caulking, weatherstripping, tape or gasket. For example, caulking can be used between the baseboard and a wall as well as between the baseboard and the floor, linking the air sealing qualities of three building components.