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SESK: Stuff Everyone Should Know · sesk.info/home-r-value

What does an insulation's R-value measure?

How well it resists heat flow. Higher is better.

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  1. How well it resists heat flow ✔
  2. How much it weighs
  3. How well it blocks sound

Why: R-value is a measure of insulation's ability to resist heat traveling through it. The higher the R-value, the better the thermal performance.

Huh, didn't know that: Common fiberglass, cellulose and mineral wool insulation gives roughly R-3 to R-3.5 per inch.

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Why would a father freeze himself? To lower his heating bill.
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References

Answer: How well it resists heat flow. R-value is a measure of insulation's ability to resist heat traveling through it. The higher the R-value, the better the thermal performance.

  1. ENERGY STAR: Recommended R-values www.energystar.gov/saveathome/seal_insulate/identify-problems-you-want-fix/diy-checks-inspections/insulation-r-values
    R-Value is a measure of insulation's ability to resist heat traveling through it. The higher the R-Value the better the thermal performance of the insulation.
    Checked 2026-10-10.
  2. ENERGY STAR: Check your attic insulation www.energystar.gov/products/ask-the-experts/how-to-check-your-homes-attic-insulation-level
    Just take the depth in inches x 3 to get an estimated value.
    Checked 2026-10-10.

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