Polyiso Insulation R Value Thickness

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 insulation r value thickness.

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. Understanding r value thursday december 13 2018 what does r value mean. 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.

Getting the interim update. 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. Keep in mind that polyiso s r value increases with thickness. The polyisocyanurate insulation manufacturers association.

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. Thickness in nominal thickness mm lttr maximum flute span in maximum flute span mm 1 00 25 4 5 7 2 625 66 70 1 30 31 7 7 4 3 675 93 35. R values for commonly available thicknesses of polyisocyanurate insulation board.