Insulation Slate Roof

Insulation laid so that it covers the eaves significantly reduces ventilation to the roof.

Insulation slate roof.

3 before you start do your homework. Understand headlap read about the common mistakes people make when installing slate roofs. You would first have to create a vent channel under the slates by installing 1x1 sticks at the top of each rafter bay followed by stiff material like rigid foam or plywood. Check the depth between your trusses and the slates then install the correct thickness of kingspan in the gaps allowing for a 25mm air gap between the kingspan and the slates.

Insulation is often laid in contact with the roofing felt. If you want to insulate the sloping roof you definitely don t want to install spray foam against the back side of the slates. It is vapor permeable and air leaky. Ice water shield.

If you create an air space under the roof sheathing boards as dana suggests there is no need to have any soffit vents or ridge vent. Slate is a wonderful forgiving roofing. Read about how to install starter courses take a look at common contractor errors watch some video clips read about drip edges and cant strips if necessary look at some of the nuances that may be pertinent to your installation such as cleats on aprons cleats on. The materials used to insulate under the roof include batts of mineral or glass wool insulation held in place by battens of wood attached to and across the rafters alternatively polystyrene.

Answered 14th jan 2013 like 2.