Rigid Foam Insulation Board R Value

That said the long term r values of this foam board decline over time.

Rigid foam insulation board r value.

Insulfoam rigid foam is a high performance built to spec sheathing insulation that provides superior r value and moisture resistance. It is offered in multiple thicknesses and dimensions in both square edged and tongue and groove joints. Polyisocyanurate foam board 1 inch thick. Rmax r matte plus 3 1 2 in.

Extruded polystyrene foam board 1 inch thick 5. A popular rigid insulation choice xps features an initial r value of r 5 per inch. For example after just 5 years an xps board will see its r value fall by 10 and even more going forward. Rigid insulation is usually made up of fibrous materials or plastic foams.

The fibrous materials such as wood cane or vegetable fibers are mixed with fillers and binders to form insulation boards. Expanded polystyrene insulation is similar to the foam used for packing peanuts and it s typically used for insulated concrete forms also knows as icf s. Expanded polystyrene foam board 1 inch thick 3 8 4 4. Rigid insulation r value by comparison usually ranges from r 4 0 to 6 5 and may get as high as r 8 7 depending on the insulation material.

Our r value guide to rigid insulation includes the doe s recommended insulation by zone chart r value calculator and base building material r values chart. In severe cold xps panels do see an increase to their r values.