R-value
A measure of the resistance of a glazing material or fenestration assembly to heat flow. It is the inverse of the U-factor (R = 1/U) and is expressed in units of hr-sq ft-ºF/Btu. A high-R-value window has a greater resistance to heat flow and a higher insulating value than one with a low R-value.Not quite sure what the proper home improvement terms are? Let us help. We have put together a glossory for you to learn a little bit more about Home Improvement Glossary and Terms
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