Mich. Admin. Code R. 408.30533 - [Effective until 8/29/2025] Frost closure
Rule 533. Section P3103.2 of the code is amended to read as follows:
P3103.2. Frost closure. To
prevent frost closure, every vent extension through a roof shall be not less
than 3 inches (76 mm) in diameter. Any increase in the size of the vent shall
be made inside the building with a minimum of 1 foot (305 mm) below the roof or
inside the wall.
Notes
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Rule 533. Section P3103.2 of the
P3103.2. Frost closure. To prevent frost closure, every vent extension through a roof shall be not less than 3 inches (76 mm) in diameter. Any increase in the size of the vent shall be made inside the building with a minimum of 1 foot (305 mm) below the roof or inside the wall.