Mansard Roof Insulation

The illustration to the right shows the proper insulation of this style of roof.

Mansard roof insulation. Originally i was toying with the idea of closed cell spray foam for the whole mansard floor but i do not want to tear down historic plaster. One strategy would be to incorporate the attic into the conditioned space and then use a sandwich of barriers and insulation under a furred vented. To insulate the roof you will need to use a combination of insulation to fully protect the roof. But what materials should be used to save energy on this type of house.

I have a house with mansard roof in boston. If the attic space remains uninhabited the air in the under roof space serves as a good thermal insulation along with the insulation of the floor. After having dense pack installed in the building walls the mansard is the next target. 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.

I recently purchased a home with a mansard roof i had some roofers come to give quotes to replace the top it is finished and they all recommend adding ventilation known issue with mansard s. Step 1 add a vapor barrier. 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. Mansard and gambrel style roofs have always been hard to insulate.

This barrier may not be fitted to an older home and you should consider getting a contractor. Here the insulation is very close to the roofing material and the task is not.