Fiberglass insulation

How do R-values of glass wool insulation differ?

Glass wool insulation has low thermal conductivity, reducing heat entering the building. It also absorbs sound, such as rain on metal sheet roofs, does not spread fire under ASTM E84 and BS 476, is not damaged by termites or mould, and recovers well after compression. The higher the density and thickness, the higher the R-value.

How do you install glass wool insulation above a ceiling?

• Open the ceiling board in the area to be insulated and carry the insulation rolls up.
• Roll the insulation out along the ceiling to cover the whole area.
• If the foil tears, repair it with aluminium foil tape.
• Leave about 3 inches clear of downlights to prevent heat build-up.

On a new metal sheet roof, lay the insulation across the purlins supported by wire mesh. On a concrete slab roof, fix it with anchors and washers, taking care not to affect the structure.