Fiber, foam, and air January 19, 2007

Our office is currently investigating building systems and assemblies as part of a larger initiative to evaluate our role in making "green" buildings. One recent presentation focused on insulation materials: fibers, foams, and air.

Two of the most interesting findings:
1. Still air has an R-value per inch of 5.5. Most manufactured products struggle to be that high; in fact most are just trying to make the air in a cavity stop moving. (This is how a down jacket keeps you warm.)
2. R-values are roughly the same across a single insulation type. For instance, fiber-based insulation, including fiber-glass, blown cellulose, and cotton and wool batts all have roughly the same R-value per inch of material; about 3.5. (R3.5 x 5.5" cavity = R19.25)

One of the most promising resources we discovered was a company promoting bio-based insulation materials, including a soy-enriched, water-blown, closed cell foam.

And, for your inner chemist, check out this product, available from BASF in Germany: phase-changing powder.