window U-factors

[88twin]

table 502.3 06 IECC. we are zone 5.

some one explain..."framing materials"?

is it not refering to window framing materials?

 

[Dr. J]

This is indeed refering to window framing materials. Wood or vinyl windows have a different U factor requirment than aluminum windows.

 

[88twin]

the phrase "framing materials other than metal with or without metal reinforcement or cladding"

was what through someone off, thinking it was refering to building framing rather than window frame.