Air Barrier Assemblies

An air barrier assembly is a collection of air barrier materials (ie. self-adhered sheet air barriers, liquid applied membranes, medium density sprayed polyurethane foam, mechanically fastened commercial building wraps and boardstock air barriers) and air barrier accessories (ie. sealants, tapes and transition membranes) assembled together to form a continuous barrier to air infiltration into the environmental separator. The performance of an air barrier assembly is of far greater importance that the air permeance of the material. When materials and accessories are installed proficiently, the benefits of the assembly have positive benefits for the entire life cycle of the building.

Testing of Air Barrier Assemblies

The testing of an air barrier assembly for air leakage is completed in accordance with ASTM E2357 Standard Test Method for Determining Air Leakage of Air Barrier Assemblies. ABAA defines an air barrier assembly as one that has a air leakage rate less than 0.2 L/(s•m²) @ 75 Pa (0.04 cfm/ft² @ 1.56 lb/ft²). Specimen one of the test is a 8' x 8' wall with exterior panel-type material. The joints are sealed and the air barrier is applied to form a continuous assembly. The second specimen is a 8' x 8' wall with exterior panel-type material, a 24" x 48" window rough opening, masonry ties, junction boxes, galvanized duct and a PVC pipe. The panel joints and penetration joints are sealed and the air barrier material then applied. The cumulative results of this test specimen will include the air permeance of the material, accessories, air barrier components (window and services elements) and the air leakage that results from joining those three parts together. See the image below for the specimens tested as per ASTM E2357.

Specimen 1 - Opaque Wall

Specimen 2 - Continuity at Penetrations

Foundation Interface and Opaque Wall (with Modifications)

Air Barrier Assembly Test Requirements for ABAA Listing

For an assembly to be listed on the ABAA website, manufacturers must provide a E2357 test report, information (ie. master spec and/or installation instructions) on what materials (thickness installed – if applicable), accessories and their sequencing around the components and other sources of potential air leakage were used. This testing method is a major benefit to the design professional as issues such as air sealing and installation methods are dealt with by the manufacturer and proven in a controlled environment rather than the design professional using a trial and error method in the field.

The issue of installation is also dealt with in that the manufacturer must declare the level of skill required to assembly the various materials. When the assembly is put together for testing, the installers will have the skill level required and declared by the manufacturer. If there are no requirements – “anyone can do this”, then that is the type of person used to assemble the specimen for testing purposes. If the manufacturer sends his most qualified engineers to assemble the test specimen, then they are declaring that they must use people of this caliber to install their material in the field. Most manufacturers declare that their installers have to be trained in their installation instructions and prove that they have the knowledge to install the materials properly by being certified.

ABAA Evaluated Air Barrier Assemblies