Attic Insulation

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Attic Insulation

What is Attic Insulation?

Attic Insulation, A thermal barrier installed in attic floors or rafters to reduce heat loss and improve energy efficiency.

Description

Attic Insulation slows conductive and convective heat transfer between the conditioned space and the attic, lowering heating and cooling loads. Common types include blown cellulose, fiberglass batts, mineral wool, and spray foam. Recommended R‑values range from R‑38 to R‑60, depending onthe climate zone. Proper air sealing, ventilation, and baffle installation prevent moisture and ice dams while maximizing insulation performance.

FAQs

  • How much insulation is needed?

    Codes call for R-38 in mild climates up to R-60 in cold regions.

  • What is the best type of attic insulation?

    Blown cellulose and fiberglass are cost-effective; spray foam adds air sealing.

  • Can insulation come into contact with the roof sheathing?

    Baffles maintain a 1-in ventilation gap at the eaves.

  • Who installs attic insulation?

    Insulation contractors using blowers or batt placement.

  • Does insulation settle over time?

    Cellulose may settle 10%, so installers over-blow the initial thickness.

  • Is a vapor barrier required?

    In cold climates, kraft-faced batts or vapor retarder paint limit moisture.

  • Can you add new insulation over old?

    Yes, if existing material is dry and free of mold.

Fun Fact

Fun Fact: The Oak Ridge National Laboratory found that attic insulation returns its cost within 3–5 years through energy savings.

CSI Code

07 22 00

NAHB Code

720