501w from BioBased Systems Created: October 12, 2011 BioBased Technologies offers its 501w, water-blown, open-cell, 5lb. foam that expands to 100 times its size. It has an R-value of 13 at 3 1/2 in. and is ICC and Class 1 fire rated. Want to know more about this product? Click here to request more information about 501w from BioBased Systems .