On new build or replacement pitched roofs the ideal build up would be insulation fitted over and then between the rafters giving a big boost for airtightness image credit.
How to insulate over t111 roof.
Talking about metal roof insulation this thing is one of the most challenging things people work in this field is facing it demands and requires excellent skill and expertise which you may only get from a reputable roofing contractor.
Ice water and cause insulation breakdown.
Msquared48 structural 11 nov 11 20 31.
They also provide another layer to seal air leaks but still let the moisture out.
I have not found any problems behind the t1 11 that i have removed.
How to install insulation board over an existing roof membrane.
So if you do an inside vapor retarder layer 3mil be careful to seal things well.
In this article we are going to explore both financial and technical aspects when it comes to looking for the best method to insulate the metal roofing.
Things like tyvek on the outside under the t1 11 do help by providing a drainage plain and keeping water leaks away from the fiberglass.
The current house has thermo ply over the studs then rigid insulation then t1 11.
It is an acceptable practice to install a new roof over an existing roof membrane system provided that the roof deck is.
The current trend is for a warm roof where insulation is installed between the rafters thereby keeping the roof timbers warm.
It is 20 years old and so far has fared pretty well.