Mich. Admin. Code R. 408.30522a - [Rescinded effective 8/29/2025] Vapor retarders
Rule 522a.
Section R601.3 of the code is amended to read as follows:
R601.3. Vapor retarders. Class I or II
vapor retarders shall be provided on the interior side of frame walls in zones
5, 6, 7, 8, and marine 4.
Exceptions:
1.
As permitted in table R702.7.1.
2.
Class III or no vapor retarder shall be permitted on the interior side of below
grade wall assemblies. Class I or II vapor retarders shall be permitted on the
interior side of the wall assembly when no air permeable insulation is
installed in the below grade wall assemblies.
3. Construction where moisture or its
freezing will not damage the materials.
Notes
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Rule 522a.
Section R601.3 of the
R601.3. Vapor retarders. Class I or II vapor retarders shall be provided on the interior side of frame walls in zones 5, 6, 7, 8, and marine 4.
Exceptions:
1. As permitted in table R702.7.1.
2. Class III or no vapor retarder shall be permitted on the interior side of below grade wall assemblies. Class I or II vapor retarders shall be permitted on the interior side of the wall assembly when no air permeable insulation is installed in the below grade wall assemblies.
3. Construction where moisture or its freezing will not damage the materials.