Common Names: Fiberglass, Rock Wool
Colour: Pink, yellow, beige, white or grey
Thermal Resistance: RSI - .022/mm R-3.2/in. Fair
Capacity to dry out if wet: Good to excellent
Fire Resistance: Good to excellent
Fungus / Vermin Resistance: Good to excellent
-- Skin irritant: Wear long-sleeve shirts and cotton masks. Some new brands of both glass fiber and mineral wool are specifically designed to not itch.
-- Does not fit readily into uneven spaces.
-- Most economical insulation for filling exposed cavities.
-- Available in a wide variety of sizes.
-- Excellent quality.
-- Easy to install.
-- Compressed batts lose some of their thermal resistance.
-- Always order batts by both R value and thickness, as they vary greatly.
-- Attached Kraft paper is not a good air barrier and is no longer available in Canada although still standard in the US. If installed in Canada, they require a fire rated covering and an additional air barrier.
-- Batts made for 2x6 stud wall cavities and larger must be installed with great care, as simply pushing into place leaves a vertical triangular channel between the back of the stud and the sheathing for the full height of the wall, creating serious condensation problems. Push it firmly back and then pull the face forward, flush up front. Fill the cavity!
-- Significant difference in R-value has been measured between batts manufactured in the US and those in Canada because they are made to different standards with different tolerances. The Canadian batts often measure closer to advertised R value.
-- Attics, unfinished walls, foundation walls with a stud structure, floors and crawl spaces, generally not in contact with the earth.
-- There are the most widely used insulations in Canada.