Fitting Roof Insulation Board

Hack n stack sealed foam board between the rafters would be better since it s at least an air impermeable insulation but even that would require a vent gap below the roof deck to meet code and you d still be under r38 on that 2x6 rafters unless you fattened it out per holladay s recommendation.
Fitting roof insulation board. Rigid foam insulation also known as insulating boards provide high r values. Here is how we cut and fit our pir insulation to insulate the walls and roof of the house. Rigid roof insulation board. Make sure the insulation is 50mm below the actual roof which can be done using the battens as your measuring gauge for the breathable area between the roof and the insulating material.
It s light weight provides ease of handling. Rigid insulation is one of the best tools to reduce your energy costs. Composed of a closed cell polyisocyanurate foam core bonded in the foaming process to 1 2 thick duraboard an expanded perlite mineral aggregate board on one side and a fiber glass reinforced facer on the other. You can even place it under the foundation slab.
Install it anywhere from the roof to the foundation. They keep your home at a comfortable temperature without the need to crank your heat. With all the insulation board in place start at the top of the roof and fix the vapour barrier. Before fitting any insulation to the sides of a pitched roof space any repairs to the roof should be completed once the insulation is in place it will be harder to spot any leaks inside the roof and any leaks will soak the insulation itself.
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. Depending how deep your rafter is you may be able to fit two layers of 100mm thick wool insulation. Insulation cover boards training and education take advantage of industry leading training and education though care the center for the advancement of roofing excellence. With a warm roof the usual process is to split the insulation into two layers.