Mansard Roof Insulation Details

If you insulate a roof with cellulose you either need a a ventilation channel between the top of the insulation layer and the underside of the roof sheathing or b an adequately thick layer of rigid foam on the exterior side of the sheathing hard to do with.

Mansard roof insulation details.

Ensure that a clear ventilation path is maintained from eaves to ridge where insulation is positioned between the rafters. A mansard or mansard roof also called a french roof or curb roof is a four sided gambrel style hip roof characterized by two slopes on each of its sides with the lower slope punctured by dormer windows at a steeper angle than the upper. One of the best ways to protect your mansard roof from the problems of ventilation is to use a vapor barrier on the inside. Establish the correct number of courses of mansard tiles to maintain minimum headlap of 65mm.

I ve already lagged the loft but cannot get access to the cavity between the roof and upstairs walls from the loft. I have a house with mansard roof in boston. This barrier may not be fitted to an older home and you should consider getting a contractor. John in my opinion both slopes of a mansard roof the very steep lower roof and the shallow upper roof are roofs not walls.

Lap the roof underlay over the mansard underlay by minmum 150mm. Here s a diagram of the house from the side. Here s the house from the front. To insulate the roof you will need to use a combination of insulation to fully protect the roof.

Mansard roof with mansard tiles. The steep roof with windows creates an additional floor of habitable space a garret and reduces the overall height of the roof for a given number of. Step 1 add a vapor barrier. After having dense pack installed in the building walls the mansard is the next target.

There s a lot of heat loss from where the roof comes down the sides.