Why is our house blue? This blue rigid foam board is one of the many advanced energy features that Glavin Homes will be presenting in the 2014 NW Natural Parade of Homes. Besides the R21 in the walls this rigid board adds an additional R5 around the entire exterior of the house. Did you know that every 2X6 only has an R5 insulating property? This means that at the exterior walls where there is a stud, beam, corner, or any piece of wood the effective R-value at this point is R5. Most houses have a stud every 16″, plus all the extra wood for other purposes. This means that a standard code house, that is supposed to be R21, has an effective R-value of R11 to R13. By putting R5, around the entire exterior of the house, the effective R value of the walls is increased, approximately, by a whopping 28% to 33%! This is just one of the things that Glavin Homes is doing. Stay tuned for more.