illustration of batts attic insulation
Illustration: Zohar Lazar
« »


This flexible insulation material is most often packaged in rolls that come in various thicknesses and standard widths, usually 16 inches and 24 inches, to fit between joists or studs in a house's framing. They come with or without a paper or foil facing that acts as a vapor barrier. You add one or more layers to achieve the desired level of insulation.

They work best for:
• Attics with standard joist spacing, especially those with no insulation
• Attics with few obstructions or penetrations to work around
• Attics with sufficient headroom for maneuvering during installation
• DIYers who don't mind cutting the material to fit around obstructions

Material Options:
R-value per inch: 2.9–4.3
Made of: Recycled glass or sand that's melted and spun into fibers
Bottom line: Commonly used and inexpensive, but fibers can irritate lungs and skin (though less so than in years past, thanks to better manufacturing), and it's less effective at blocking airflow than other materials.

R-value per inch: 3.7–3.8
Made of: Fibers from recycled post-consumer paper that are treated for insect and fire resistance.
Bottom line: Won't irritate lungs or skin, but the product is made by a limited number of manufacturers.

Mineral wool
R-value per inch: 3.0–3.3
Made of: Fibers from rock or recycled slag from blast furnaces
Bottom line: It's naturally fire resistant, but the product is more expensive than others.

R-value per inch: 3.7–3.8
Made of: Fibers from recycled denim cloth
Bottom line: Blocks airflow and sound transmission, but the material is more expensive than others.
Ask TOH users about Insulation

Contribute to This Story Below

    More in Framing & Insulation