Foam board insulation: EPS, XPS and polyiso compared, where to use them and how to install
Rigid foam board insulation explained: EPS, XPS and polyiso, R-value per inch and moisture, where each works best, sealing seams and fire safety.
Solar & Energy Efficiency
Compare solar panels, heat pumps and insulation, and see what they could save on your energy bills.
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How much attic insulation do I need? Recommended R-values by climate zone
ENERGY STAR's recommended attic, floor and wall insulation R-values by climate zone, how to check what you have, and how to turn an R-value into a thickness.
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- Insulation calculator (U-value)New U-value, thickness needed and yearly heating saving.