Spray Insulation On Underside Of Roof

It really should be called spray foam insulation and air barrier.

Spray insulation on underside of roof.

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. Polyurethane spray foam metal roof insulation in order to add moisture barrier under metal roof you can spray the undersides of the roof by using a thick layer of polyurethane spray foam. In most cases the recommendations are based on mineral wool insulation to a depth of 270mm on the floor of the loft. Spray foam insulation is an incomplete name.

The roofing materials are installed and consist of timberline shingles and full coverage ice and water barrier the entire roof. A properly done spray foam job not only insulates but also greatly reduces the air leakage of a home. Watch this video on youtube. Unlike solid insulation products that require careful measurement cutting and fitting spray foam can cover even the most uneven surface instantly.

But that only works if the installer can get it into the places where most of the air leakage happens. Spraying foam on the underside of your roof is a great way to stop air from flowing out of the top of your house. You can spray foam anywhere you d like to separate the inside from the outside. The spray on foam is a rigid foam that is lightweight normally sprayed on to the underside of the roof approximately 50 to 100 mm thickness.

It s not coming from above the roof and it s not some new moisture source resulting from the spray foam. 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. 1 some manufacturers advise that the spray foam is breathable some of them say nothing at all about this. Yes you can spray foam the underside of your roof.

Lstiburek takes blame for bad language. The attic will be a conditioned space and i m planning to apply spray foam insulation to the underside of the roof sheathing. When it comes to spray foam insulation that is applied to the underside of the roof between the rafters the financial benefits are even more impressive with the initial outlay recouped within just a few years on average. 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.