1.1 This specification covers minimum performances and specification criteria for an air retarder (AR) material or system for framed walls of low-rise buildings. The intended users are purchasers of the AR, specifiers of the AR and regulatory groups. The provisions contained in this specification are intended to allow the user to design the wall performance criteria and increase AR specifications to accommodate a particular climate location, function, or design of the intended building. Air retarder performance and specification minimums were selected with the service life of the building wall in mind.

1.2 This specification focuses on ARs for opaque walls. Other areas of the exterior envelope, such as roofs, floors, and interfaces between these areas are not included in this specification.

1.3 This specification does not address air leakage into the wall cavity, that is, windwashing. No standardized test has been developed that adequately identifies all of the influencing factors and measures the impact of this effect on the wall's thermal performance.

1.4 The specifications in this standard are not intended to be utilized for energy load calculations and are not based on an expected level of energy consumption.

1.5 The values stated in inch-pound units are to be regarded as the standard. The values in parentheses are for information only and are closely approximated.

1.6 The following safety hazards caveat pertains only to the test method portion, Annex A1, of this specification. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.