What is the R-Value of Foam-Lok?
R-value is derived from a controlled laboratory test of an insulation's resistance to conductive heat flow. Foam-Lok open cell foam has an R-value of 3.9/inch and Foam-Lok closed cell foam has an R-value of 6.3/inch. The actual performance of Foam-Lok when installed in a building will perform at its lab rated value due to the air-sealing nature of the product, allowing it to stack up favorably when compared to non-air sealing, traditionally installed materials such as fiberglass batts. Fiberglass will perform nowhere near its labeled value once it is packaged, cut up, and stuffed into building cavities. So, an R-13 of foam will perform more efficiently than R-13 of fiberglass. It's confusing, but blame the government.
Are these aged values?
Yes. Most closed cell foams use a blowing agent called 245fa (also called Enovate). This blowing agent allows a 2LB density closed cell foam to maximize R-value per inch. During the curing process the millions of cells that make up the foam are filled with a gas that is much more thermally efficient than the air we breathe. The initial R-value of a 245fa blown closed cell foam will be in the neighborhood of R-7. Over a period of several months (depending on the thickness of the foam and other factors) this gas will diffuse out of the foam and be replaced with atmospheric air that we breathe, thus lowering the R-value to the low R-6 range.
If you see closed cell foam offering an R-value above 6.5 it is an initial value and you should pay no attention to it. There is no known technology that can reach that aged R-value. Open cell foam and some closed cell foams use only water as a blowing agent. The gas in those cells (CO2) is not materially different from atmospheric air from an insulating perspective and thus, they have similar initial and aged R-values. It should be noted here that water blown closed cell foam cannot reach R-values above the low R-5 range. Some manufacturers will advertise water blown closed cell foams with aged R-values above 6. That is not possible or everyone would make their foam with water since water is pretty much free.
Is there a difference between the R-value of foam and fiberglass?
R-values of insulating materials are measured in laboratories and are designated a nominal R-value per inch. In the wall or ceiling of a building, fiberglass and cellulose insulation materials suffer a reduction in performance due to air leakage and infiltration — so their "real" insulating value may be as low as 50% of the nominal R-value of the insulation they contain. Their R-value in the real world is constantly changing based mostly on temperature and wind speed.
By contrast, the insulation of a wall containing Foam-Lok will perform more closely to the laboratory tested R-value of the material and seals the wall cavity from air infiltration as well. Foam-Lok is particularly well suited to steel frame construction. Foam-Lok expands to 100 times its original size as it is installed, adhering to surrounding building components. It completely seals joints, crevices, and voids — including difficult to insulate spaces such as steel stud "U" and "C" sections, double studs, and non-standard stud locations. A continuous air and vapor barrier is formed around the building structure in a single application.