What are some alternatives to stop the thermal bridging around the windows and doors?

Asked by Doug Keaty
Albuquerque, NM

I am applying 2" of foam over my osb. Do I need to build 2X2 wood frames for my windows to be anchored to? 


Edward Wright

Answered by Edward Wright

Cincinnati, OH

Wright Design, LLC

August 22, 2012


Yes - your windows need to be secured to solid wood.  The loss of R-value at that blocking is minor - when averaged with the improvements you are making to whole wall assembly. 

Diverting water and resisting air infiltration will make a durable and energy saving assembly.

  • It is important with both windows and doors to install flashing at the head, jambs and sills, as well as
  • air sealing around the exterior perimeter and spraying minimal-expanding foam around the gap between the rough opening and the window/door.

A leaky (water + air) installation will cost much more long-term than would be saved by the additional insulation.

Good luck with your project,


Tagged In: energy efficient window, windows

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