CB

CodeBook

Building Code Research

MA Beta

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Quick Reference

Basement Insulation

IRC R402.1.2

Zone 5A — R-15 continuous or R-19 cavity

780 CMR · Stretch Code

Attic Air Sealing

IRC R402.4.1

Air barrier required at ceiling plane

780 CMR · BPI Envelope Std

Window U-Factor

IECC Table R402.1.2

Zone 5A — U-0.30 max

780 CMR · Stretch Code

Vapor Retarder

IRC R702.7

Class I or II on warm side — Zone 5A

780 CMR · BPI 3.2.1

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