I like Patrick’s comment above about providing a complete bibliography of the studies. I think the summaries are a very helpful tool to have within the Standards.
Sort of related to the various energy studies, last April I attended a workshop sponsored by the U.S. Dept. of Energy regarding its High Performance Windows Volume Purchase (WVP) Program. New window manufacturers for the program are chosen through a bidding process. For consumers/homeowners, the WVP program provides a website (www.windowsvolumepurchase.org
) that allows purchasers to compare manufacturers and high performance windows in an apple-to-apples scenario. These new replacement windows have a higher energy rating than Energy Star.
Most important for historic windows, the WVP program determined that low-E storm windows are a cost effective option for increased window efficiency. As stated in the workshop: the storms can reduce heat loss by over 50%, reduce overall home heating loads by 20%, and exceed Energy Star ratings, so would qualify for applicable energy tax credits. There seemed to be some acknowledgement during the workshop that storms are most often the more appropriate choice for historic windows, but not many of the manufacturers seem to be making them. There are some low-E storm window studies posted here - http://www1.eere.energy.gov/buildings/w ... torms.html