toddinmn wrote:
I work with a non profit that does several hundred blower door/infa-red test a year.From talking with the personel that does the testing and writes the recommendations ,the windows being the biggest leakers is a myth.It is extremely rare that they would recommend to replace windows.Either way,a blower door test is highly recommended and can be done for cheap through many local utility companies.Also here in Mn alot of the old windows do have storm windows which would seem to help.
Todd,
As I said, normally I would agree with you from the get go. Windows are not, as a general rule, the first item on the priority list when it comes to residential energy efficiency. As Dave mentioned, I am BPI Building Analyst and Envelope Professional certified. Randy out of Houston is also very educated on this stuff as well.
More recently, we have done energy audits on several homes that showed a +26% reduction in building air flow from just the replacement of their windows (installed air tight windows, foam sealed, best practices install, etc).
Those numbers are huge and we normally shoot for 30% with an entire house air sealing and weatherization retrofit. Where we are with this home, there is the risk of overtightening this home. The homeowners are two adults with no children or pets so we can go lower on the BAS scale but we will probably do a partial air sealing and re-test prior to doing the whole home. Where we are now is very close to an "Energy Star" home.
Not the rule but there certainly are some homes out there where the windows are first on the list.