Storm window to increase efficiency
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I currently have Anderson wood double pane windows. I have been kicking around the idea of removing the screen and putting clear vinyl in its place to help with efficiency. Do you think this will help or hurt efficiency?
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Hi Scott,
Storm windows do improve performance (check out the links below). However, I don't know how well your approach will work. I guess if you can get the reinstalled screen frame to not leak air around the perimeter there will be some gain, but I'd consider taking the project a step further and getting some legitimate storm windows.
https://www.greenbuildingadvisor.com/article/save-energy-with-storm-windows
https://www.greenbuildingadvisor.com/article/low-e-storm-windows-are-big-energy-savers
I planned on using felt to seal the screen frame in. My problem with typical storm window is my wife does not like the look and happy wife happy wife. lol
I've seen lots of attractive wooden storm windows that don't look like the typical metal ones. Worth researching those if you end up deciding not to go the DIY route. And if you do DIY, there's probably some ideas to be had by looking at other wooden storm windows!
LBL has a new software tool that can calculate the benefit of several common window attachments, including storms:
https://windows.lbl.gov/software/aercalc
The only way that a storm window can "hurt" is if it is more airtight than the assembly to the interior; this can mean condensation on the interior of the storm (of course, this depends on climate).
Peter
>"The only way that a storm window can "hurt" is if it is more airtight than the assembly to the interior; this can mean condensation on the interior of the storm..."
Condensation is far from the worst case scenario.
An exterior storm window that gets high sun exposure can sometimes trap enough heat to blow the seals on the insulated glass unit the main window. The higher performance the window (particularly high performance heat-rejecting low solar gain coefficient windows) the higher the risk.
Rather than clear vinyl (which has a very high solar gain coefficient), a hard coat low-E glass storm window will cut the solar gain of the storm window by about 25% limiting the peak temperature at the insulated glass unit, while improving the overall U-factor by even more than a clear glass (or clear vinyl) storm.
My windows are older and do not have the butyl sealant between the panes. They have glass panes with gap between but the glass touches at the edge.