Polyiso Insulation R Value Thickness

The r value of your insulation can optimize your energy savings in any zone.

Polyiso insulation r value thickness.

The polyisocyanurate insulation manufacturers association. R values for commonly available thicknesses of polyisocyanurate insulation board. An insulation material s resistance to heat flow is rated in terms of r value a higher r value means greater insulating effectiveness i e higher resistance to heat flow. By blocking thermal bridging a polyiso continuous insulation system increases the overall thermal performance of a wall assembly and a building.

Polyiso insulation thickness r value chart. Getting the interim update. In addition to nrca s design in service r value recommenda tions for polyisocyanurate insulation nrca recommends design ers specify polyisocyanurate insulation by its desired thickness and not lttr or r value to avoid possible confusion. 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.

Keep in mind that polyiso s r value increases with thickness. 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. Likewise for jobs that will be permitted in 2014 the design professional should specify insulation thickness based on the 5 7 r inch design guideline associated with the new lttr test method.