Air Barriers

Air Barriers are an essential component of the building enclosure. An air barrier system is a system of building assemblies within the building enclosure—designed, installed and integrated in a way that stops the uncontrolled flow of air into and out of the building enclosure.

They reduce moisture problems and heating and cooling costs, improve indoor air quality, isolate the indoor environment, and result in durable buildings.

floor barrier 2

Canteliever floors should have blocking sealed without gaps or holes. 

Blocking must be sealed without any gaps.

insulation barrier 2

knee walls 2

Blocking should be placed between any non-conditioned and conditioned space. 

Knee walls require an air barrier between the attic space and the conditioned space.

Fireplaces that adjoin an exterior wall should have insulation enclosed by a rigid air barrier.

Stairs that adjoin an exterior wall or garage should be backed with a rigid material and sealed at the seams.  

House wrap air barrier

Porch backer

Housewrap may be used (although a rigid air barrier works best) behind tubs, showers, and stairs on exterior walls.

Some covered porch to house connections require an air barrier. While not required by code best practice is to always block out bulk air that may enter into attic spaces unless required for ventilation.

Mechanical Backerdropped soffit

A rigid air barrier is required behind HVAC components and water heaters. It should be installed before the equipment is set.

Chases and dropped soffits should be capped with a rigid air barrier and air sealed.

Some covered porch to house connections require an air barrier. While not required by code best practice is to always block out bulk air that may enter into attic spaces unless required for ventilation