Windows and Thermal Performance

Are you familiar with the Traco window??  If so, how does it compare with those that you list under the "showcase" catagory???

I would like to know how to determine the R Value of an existing window, in order to perform a cost analysis for either replacement or looking into Film application, such as the 3M clear tint. I cannot recall the exact name of the product right now, I have a building that was built in 1959, single pane glass windows, according to my glass repair vendor its not even tempered. I could use some guideance.

thank you

Michael,

You can have your windows/glazing measured for thermal performance by a testing lab but it may cost more than it's worth.  Thermal imaging can also show energy loss but can't easily quantify it.  Single glazed 1/4" glass in a window will achieve about an R-1 and commercial aluminum curtain walls or windows can achieve an R-3 to R-5 but are expensive.  The highest performing window on the market is a fiberglass window with high performance glazing involving window films and it achieves about an R-11.  Unfortunately glass is not very efficient even with the low-E coatings available.  High performance window films can achieve impressive performance ratings that dramatically outperform the highest performing glass available on the market.  In addition, your building can now be modeled using DOE software with your existing glass with and without window films to show not only a KW reduction but also an ROI, which would be about 1.2 years with the highest performing films.  Unfortunately if you buy by name brand only, you can easily get an underperforming film that can make your solar gain problem worse than before.  I would be glad to discuss this further and I can be reached at phil@clear-wall.com or by calling 619-993-7595.  Best of luck in your research.