Polyisocyanurate Insulation R Value

Polyiso has a high r value per inch compared to other insulation products.

Polyisocyanurate insulation r value.

A higher r value means that the insulation will do a better job of holding in conditioned air whether that s heat in the winter or cool air in the summer. As part of that standard the products must meet r value requirements presented as long term thermal resistance lttr. As foam ages over time air and blowing agents diffuse in and out of the foam structure resulting in reduced r value. Polyisocyanurate polyiso is a closed cell rigid foam board insulation that is bonded to facers on both sides which are composed of various organic and inorganic materials.

And nrca s r value recommendations associated with the use of polyisocyanurate insulation used in roof systems. 1 2014 industry issue update polyiso s r value provided an overview of the theory of foam aging. Rigid polyisocyanurate thermal insulation board. Fm approved subject to the conditions of approval as a roof insulation when installed as shown in the current edition of the factory mutual research approvals guide.

Polyiso insulation thickness r value chart. Polyiso is used in roof wall ceiling and specialty applications within commercial and residential buildings of all types. Polyiso is unique in that the r value increases with the thickness of the foam so three inches of polyiso has a higher r value per inch than two inches. The r value test method and the long term thermal resistance lttr methodol ogy.