Rigid Foam Insulation Roof Deck

Rigid foam installation after the roof deck is ready the rigid foam insulation is installed.

Rigid foam insulation roof deck.

Rigid insulation layers exterior to existing roof sheathing must provide sufficient thermal insulation r value to control condensation risk see climate specific guidance. Rigid foam insulation is available in two main types. 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. At r 4 it also has the lowest r value per inch.

Most unvented attics incorporate spray polyurethane foam spf on the underside of the roof deck and attic walls. Eps is the most vapor permeable of the three types. Polystyrene foam and foil faced polyisocyanurate foam. There s a reason polyiso rigid foam insulation is used in more than 70 of commercial roof construction as well as in many residential builds.

They had to look original. Install roofing underlayment flashing and cladding as per best practices. Polyiso is an easy cost effective sustainable and energy efficient construction material. Nailbase must be vented in high snow load areas.

All three types of rigid foam insulation expanded polystyrene eps extruded polystyrene xps and polyisocyanurate are suitable for use on the exterior of walls and roofs though they do not perform equally. The trim the frieze boards the fascia and the overhangs all had to look like they belonged. The products are easy to handle score cut and install and no special tools are needed. Both install in the same manner but the foil faced product offers slightly more r value.

The 6 inches of rigid insulation added to the top of the existing roof deck needed to be done in a manner that was invisible. Owens corning foamular xps insulation is a closed cell moisture resistant rigid foam board ideal for many roofi ng applications including single ply protected roof membrane assemblies prma tapered vegetative roofs plaza decks architectural metal roofi ng and recover roofi ng. The purpose of the requirement that rigid foam installed above roof sheathing meet certain minimum r values is to ensure that the roof sheathing stays warm enough during the winter to avoid moisture accumulation and possible sheathing rot. Depending on the type of insulation you choose and the desired r value you want for your facility you may need to build up a few layers of insulation.