The first order of business to to strip the roof.
Roof insulation on outside.
Install roofing underlayment flashing and cladding as per best practices.
At that point what you are doing is building a r e m o t e wall read more about that here.
Install nailbase for cladding.
Nailbase must be vented in high snow load areas.
Install two layers of insulation to the roof staggering the seams offsetting the joints and taping outer layer.
R 3 graphite radiant barrier wall insulation kit 9 sheets kit model sbgxs062502pkit 51 98 51.
Buy 24 or more 22 38.
Next cut off the rafter tails so that the connection between roof and walls can be sealed with peel and stick membrane.
Installing insulation that acts as a vapour barrier on the outside will not serve you well except if you add enough of it to the point where about 2 3rds of the total insulation is on the outside.
However insulation should not block eave vents in attics because if the flow of air is blocked moisture may build up in the attic and water vapor may condense on the underside of the roof.
Ceiling insulation should extend far enough to the outside walls to cover the bottom chord of the truss.
Dry in the roof with peel and stick membrane.
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.
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.