Spray Foam Underside Of Roof In Attic

The insulation reduces wildly high temperature spikes and so the attic becomes a conditioned part of the home like any other room.

Spray foam underside of roof in 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. Attic ceiling to stop airborne moisture from reaching a cold surface and condensing inside the building envelope. Lstiburek takes blame for bad language. Unlike solid insulation products that require careful measurement cutting and fitting spray foam can cover even the most uneven surface instantly.

Spray foam insulation in an unvented attic assembly has been one of the most researched and widely implemented innovations of recent years. Insulating and providing airtightness with spray foam at the underside of the roof as part of an unvented attic assembly will elevate such concerns. Unvented attics rely on an air impermeable insulation installed to the roof deck s underside i e. In this design insulation effectively separates the interior and exterior spaces while slowing down moisture flow so the dewpoint is not achieved within the building envelope.

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. Most unvented attics incorporate spray polyurethane foam spf on the underside of the roof deck and attic walls.