NRCA has updated their R-value recommendation for polyisocyanurate roof insulation with the publication of the 2011 The NRCA Roofing Manual: Membrane Roof Systems. The new recommendation for R-value ...

Most people don’t devote much time to thinking about roof insulation ... The material used for the rigid insulation board will affect the R-Value as well as the cost; the higher the R-Value ...

The R-value for insulation is ... a number of decisions to make about the insulation including what’s best for the floors, walls, crawlspaces and the roof. However, for the majority of people ...