402.2 Specific insulation requirements (Prescriptive).
- 402.2.1 Ceilings with attic spaces.
When
Section 402.1.1 would require R-38 in the ceiling, R-30 shall be deemed to satisfy the requirement for R-38 wherever the full height of uncompressed R-30 insulation extends over the wall top plate at the eaves. Similarly, R-38 shall be deemed to satisfy the requirement for R-49 wherever the full height of uncompressed R-38 insulation extends over the wall top plate at the eaves. This reduction shall not apply to the
U-factor alternative approach in
Section 402.1.3 and the total UA alternative in
Section 402.1.4.
