Code Change Proposal Tightens Window Efficiency; Allows Flexibility if Combined with Other Efficient Features
October 27, 2009

The International Code Council's Code Development Hearings are currently underway in Baltimore. A number of code change proposals for the International Residential Code (IRC), building/energy, were presented before the IRC committee earlier today.

The National Association of Home Builders EC16 (part 2) was one proposal that was approved. This will reformat the prescriptive table to include various alternative prescriptive "packages" with different combination of envelope values, home air leakage, duct leakage, and equipment efficiency. It tightens the efficiency of window requirements across the board, but also provides flexibility to use different window values if a homeowner has efficient HVAC equipment, home air leakage, etc.

In addition, proposal EC36 was also approved. This will add a new column with separate and higher solar heat gain coefficient requirements for skylights, as they are different from [vertical] windows.

Proposal EC74 was also approved, which allows a trade-off for SHGC in zones 1-3 based on the amount of shading provided by overhangs.

Some of the disapproved proposals included attempts to remove the allowance footnote for hurricane products (EC35), and limitations on overall glazing area to less than 20 percent (EC31).

Stay tuned to USGNN.com™ for more code hearing updates as they are made available.

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