Spray On Foam Roof R Rating

In comparison an inch of blown fiberglass insulation has an r value of 3 1 3 4 and an inch of blown cellulose in an attic has an r value of 3 2 3 7.

Spray on foam roof r rating.

Although spray foam insulation has been in use since the 1940s primarily for aircraft for the past 30 years continual product innovation has seen the increased adoption of spray foam insulation in residential and commercial construction. For 6 inches r 15 or r 19 etc. Amongst all of the popular types of insulation currently used by the industy spray foam insulation features the highest r value per inch. Spray foam insulation r values.

A typical 2 4 stud filled with open cell spray foam will have an r value between 10 5 and 14. The most common problems that occur around the use of icynene is the belief that it can have a negative effect on the roof of the loft. Today we discuss one of the highest performing and most affordable roof systems in commercial roofing spray polyurethane foam. Encapsulating the rafter or top truss chord roof framing members with spray foam will improve the energy efficiency of the attic space.

A spray foam roof can be the last roofing system you ll ever need on a building. But despite the fact that it has been around for 50 years some members of the public have strong. Causing the timbers to rot. However fiberglass generally does not provide as tight a seal as a foam product would since it is unable to achieve as tight of a seal.

This is not an issue specific to spray foam as much as it is a characteristic of peel and stick membranes. The rapid growth of sprayed foam insulation in building construction thanks in part to its immediate and long term. Why spray foam insulation is so effective in meeting code requirements is that it has a higher r value per inch of product used than batts. For example energy star recommends r 30 for a roof in the southern united states r 38 for the middle of the country and r 49 for the northern part of the country.

Due to spray foam insulation being such an upcoming method of insulation there have been quite a few misconceptions about the effectiveness and dangers of its use. Closed cell spray foam r values. Wood has an r value of about one per inch of thickness. Additional r value for a masonry wall constructed using these materials needs to add the insulating value of additional wall components typically included such as 1 solid foam polyisocyanurate r 8 extruded polystyrene r 5 expanded polystyrene r 4 or 1 of perlite r 2 7 and for an exterior air film winter no wind r 0 17 an interior.

For example closed cell spray foam depending on brand can offer an r 6 or r 7 per inch. Since a spray foam system consists of spray foam coating and granules after 10 20 years some of the coating and granules will naturally wear away. The foam never gets touched and never loses r value. This r value is similar to that of r13 fiberglass batting.

At year 10 20 a contractor will add more coating and granules.