Roof Insulation Boards Between Rafters

Being lightweight they do not impose significant additional loads on existing structures.

Roof insulation boards between rafters.

Depending on the specifics of the roof it may be possible to fully fill the rafter depth or in most cases leave a 25mm or 50mm air gap between the top face of the insulation and the sarking membrane. Easiest insulation for layperson to install fairly inexpensive r value doesn t fluctuate as with loose fill. Https youtu be w4mkphzmqxw contact us restorat. Check out our how to video at the link below.

For an un ventilated roof construction a vapour open underlay or breather. Once up at roof level the between rafter boards can be cut accurately to fit the rafter spacings. For a ventilated roof fix battens on the inside of the rafters 50mm from the underlay to leave vented air spaces. This means insulating between or below the sloping beams that form the construction and support a sloping roof.

For a new build or if a detached dwelling is being re roofed then there is scope to choose the build up of roof that suits your purposes best however if the roof insulation is being added to an existing roof for example as part of a loft. Install underlay above the rafters. R value for fiberglass or wool batts per inch is between r3 and r3 5. Insulating the rafter space will give you a warm loft.

Having chosen to insulate your rafters and potentially use the loft space as an extension of your living area you need to be aware of some safety features before you read on. Where the insulation does not fill the total rafter depth the low emissivity foil facings can gain additional thermal benefit from the air spaces they face into. Quinn therm qr roof insulation boards are recommended for installing insulation above and between the rafters given the excellent thermal properties combined with the lightweight and easy to cut and install features of these rigid pir insulation boards. Measure the space between the rafters where the insulation.

2 measure and cut the foam boards as. Rolls are usually used for long expanses such as length of floor for entire attic while batts are fit between studs in attic rafters. Rigid polyisocyanurate pir foam insulation boards from celotex are among the most thermally efficient commonly available insulation materials on the market. Select rigid foam insulation boards that are at least 1 2 inch less in thickness than the rafter space is deep if you plan to finish the attic as living space.