Please compare and contrast the benefits of open cell insulation compared to spray foam insulation in regards to window installa
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Bradley Williamson| Posted inEnergy Efficiency and Durabilityon
I want to learn about the pros and cons of using open cell insulation and closed cell spray foam insulation in regards to window installation.
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Replies
Usually spray foam insulation is not used directly up against windows, either open or closed cell. Exceptions would be a fixed, not moving parts window, where the gap between the rough opening framing and the window frame is large.
A specific foam to seal around doors and windows is a single component foam designed to be low expansion and easily dispensed from a can. I use Hilti door and window foam. Other brands are Dap, Great Stuff, and many others.
Open cell is a form of polyurethane spray foam insulation that is installed at a typical density of 0.5 pcf, and closed cell is another form of polyurethane spray foam insulation that is installed at a typical density of 2.0 pcf. Open cell has a typical R-value of 3.4/inch while closed cell is typically 6.5/inch. Open cell is somewhat vapor open while closed cell is a vapor barrier.
They are used only for insulating large volume areas, not window openings.