Montana Building Codes Council Votes to Adopt 2009 IECC, Require Basement Insulation

On June 25, 2009, the Montana Building Code Council voted to adopt the 2009 IECC with amendments. The Montana Department of Labor and Industry will be accepting comments on the new code when the department holds the public hearing as part of the administrative Rules process, which should take effect in fall of 2009.

The existing Montana amendment allowing residential basement insulation delay until the space was finished for occupany was removed.

The word "into" the building envelope was inserted in the definition of Air barrier in section 202. Table 402.1.1 for Zone 6 was amended to list R-21 for wood framed wall R-value. and Crawlspace wall R-value was amended to; R-10 foam insulation or R-19 fiberglass. The existing log wall - R-value exemption amendment - was not voted on. Section 402.4.2.1 Testing option was amended to list - less than four air changes per hour. Table 502.2(1) Zone 6 - Wood framed and other was amended to list R-13+7.5 or R-21.

Public comments will be taken on the Building Code Council decisions before the administrative rules are authorized.

For more information about the 2009 IECC code or the adoption process, contact Paul Tschida at Montana DEQ at 406-841-5232 or email ptschida@mt.gov.