Polyurethane or polystyrene spray foams can provide thorough coverage to roof rafters and attic walls in much less time than is needed for other materials.
Spray foam insulation under roof deck.
But that only works if the installer can get it into the places where most of the air leakage happens.
Financially speaking this spray is a great option especially when you need to renovate your roof after the application.
Install spray foam insulation along the underside of the roof deck to create an insulated unvented attic which can provide a conditioned space for hvac equipment that is located in the attic.
This construction approach was first used in the 1970s and it has been implemented much more widely since it was first included in the international code council s icc model building code in 2007 irc section 806 4.
It really should be called spray foam insulation and air barrier.
Unlike solid insulation products that require careful measurement cutting and fitting spray foam can cover even the most uneven surface instantly.
Most unvented attics incorporate spray polyurethane foam spf on the underside of the roof deck and attic walls.
A properly done spray foam job not only insulates but also greatly reduces the air leakage of a home.
Open cell spray polyurethane foam ocspf and closed cell spray polyurethane foam ccspf insulation sprayed to the underside of roof sheathing is a popular strategy for increasing roof insulation levels in all climate zones.
The standard means of disposal of spray foam scraps is to dispose in normal construction waste to a landfill.
It s not coming from above the roof and it s not some new moisture source resulting from the spray foam.
Moisture generated indoors or that infiltrates into the home is responsible for the bulk of the moisture in an attic insulated with spray foam on the underside of the roof sheathing.
Lstiburek takes blame for bad language.
Spray foam insulation is an incomplete name.
The spray foam can also serve as the thermal and vapor control layers in both new and retrofit construction.
Compared to the fiberglass batts this insulation is much better.