Effective June 1, 2009

1323.0543 SECTION 5.4.3, AIR LEAKAGE

Subpart 1. Building envelope sealing. ASHRAE Standard 90.1, Section 5.4.3.1, is amended and subsections added to read:

5.4.3.1 Building envelope air sealing. The building envelope shall contain an air barrier consisting of a material or combination of materials to resist the passage of air into or out of the conditioned or semiconditioned space. The following areas of the building envelope shall be sealed in a permanent manner to minimize air leakage at all edges, joints, openings, and penetrations:

1. joints around fenestration and door frames;
2. junctions between walls and foundations, between walls at building corners, between walls and structural floors or roofs, and between walls and roof or wall panels;
3. openings at penetrations of utility services through walls, roofs, and floors;
4. site-built fenestration and doors;
5. building assemblies used as ducts or plenums;
6. joints, seams, and penetrations of vapor retarders;
7. across construction, control, and expansion joints;
8. across junctions between different building assemblies; and
9. around all other penetrations through the building envelope.

5.4.3.1.1 The air barrier shall be located between the warm-in-winter surface and the winter design dew point location within the building component or assembly.

Exception: When the building component or assembly is either integrally insulated concrete or integrally insulated concrete masonry.