Roofing Code: Insulation and Fenestration Criteria

International Energy Conservation Code

Section 402.1.1   Insulation and fenestration  criteria

The building thermal  envelope will meet the requirements of Table 402.1.1 based on the climate zone specified in Chapter 3 of the IECC.

Code Interpretation

This code implies that there are prescribed thermal R-values for residential ceilings. The R-value is based on the climate zones identified within the International Energy Conservation Code.

Climate Zone  Ceiling R-Value

• 1          30
• 2          30
• 3          30
• 4          38
• 5          38
• 6          49
• 7          49
• 8          49

 Note: 402.1.2 R-value computation indicates that R-value shall be based solely on insulating material and shall not include other building materials or air films.