Common Name: Rock Wool loose fill.
Colour: Brown or white
Thermal Resistance: RSI - .019/mm R - 2.7/in. Fair
Cost: Medium plus blower.
Capacity to dry out if wet: Good.
Fire Resistance: Excellent.
Fungus / Vermin Resistance: Good to excellent.
Limitations:
-- Skin irritant: wear long sleeve shirts and cotton masks.
-- Heavy: may compress other insulation or overload weak ceilings.
-- Requires professional blowing equipment and experience to obtain proper density.
-- Fibers prevent good flow in closed spaces; difficult to fill all parts of a wall, although easier than with blown-in Glass Fiber.
-- Can settle
-- Low R value per inch.
Advantages:
-- Very high resistance to fire.
-- Little air current penetration.
Notes:
-- Ensure that it does not plug eave vents at the time of installation and that it does not blow over the vents later with normal attic air currents.
Applications:
--Attics and unobstructed closed cavities, but for limitations search keyword "walls" for the title "CONFLICT: USE OR DON'T USE BLOWN-IN LOOSE FILL INSULATION INSIDE HOLLOW WALLS."