The best way is to insulate the attic floor.
Slate roof insulation.
There are different types of roof shingles roof tiles and paneling some more decorative and others more functional.
If 180mm is to be installed then 100mm board might be introduced between the rafters there has to be a minimum 25mm air gap between the insulation and the underside of the tiles or slates with an 80mm board running across the rafters.
Standard thickness roofing slates 3 16 inch to 1 4 inch that have drilled holes without counter sinking are sub standard slates.
Slate roofing 3 8 inch slates.
Slate roofing 1 4 inch slates.
Slate roofing 3 16 inch slates.
Asphalt shingles are a good basic go to with a relatively low initial.
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.
Slate roofs national slate association 1926.
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.
Answered 14th jan 2013 like 2.
Many slate tile manufacturers offer up to 100 year warranty on their products.
After installation the nail heads will rub against the overlying slates and eventually wear holes in them.
Http www spraysealroofinsulation co uk spray foam insulation being applied to the underside of a slate roof.
A slate roof can cost from 12 to 40 per square foot according to websites and roofers i consulted.
A well ventilated roof space is good this stops your timbers rotting.
Roofing felt was introduced primarily to act as a secondary barrier against wind driven snow and rain but its use also causes a reduction in air movement within the roof space particularly if the roofing felt is impervious and this effect is often compounded by the introduction of insulation.
With a warm roof the usual process is to split the insulation into two layers.
For people who do not plan to ever sell their home the incredible longevity of slate is a highly desirable benefit.
Depending on what roof type you choose for your structure you may be using roof tiles ridge caps roofing sheets underlayment and roof insulation.
Your price will be on the lower end if you use recycled slates or reinstall your own.
A slate roof will easily last over 100 years which is at least double of what other roofing materials can offer.
If you want to insulate the sloping roof you definitely don t want to install spray foam against the back side of the slates.