Minn. R. agency 151, ch. 1323, pt. 1323.0543 - SECTION 5.4.3, AIR LEAKAGE

Subpart 1. ASHRAE 90.1 section 5.4.3.1 Continuous air barrier.

ASHRAE 90.1 section 5.4.3.1 is amended by deleting exception 1.

Subp. 2. ASHRAE 90.1 section 5.4.3.1.1 Whole-building air leakage.

ASHRAE 90.1 section 5.4.3.1.1 is amended by adding exception 4 to read as follows:

4. For buildings or portions of buildings enclosing Group R or Group I occupancies, the measured air leakage shall not exceed 0.30 cfm/ft² (1.5 L/s m²) of the testing unit enclosure area at a pressure differential of 0.2 inch water gauge (50 Pa). Where multiple dwelling units or sleeping units or other occupiable conditioned spaces are contained within one building thermal envelope, each unit shall be considered an individual testing unit, and the building air leakage shall be the weighted average of all testing unit results, weighted by each testing units enclosure area. Units shall be tested separately with an unguarded blower door test as follows:

a. Where buildings have fewer than eight testing units, each testing unit shall be tested.

b. For buildings with eight or more testing units, the greater of seven units or 20 percent of the testing units in the building shall be tested, including a top floor unit, a ground floor unit, and a unit with the largest testing unit enclosure area. For each tested unit that exceeds the maximum air leakage rate, an additional two units shall be tested, including a mixture of testing unit types and locations.

Notes

Minn. R. agency 151, ch. 1323, pt. 1323.0543

39 SR 1605 47 SR 983