This house makes use of CBF Ultra radiant barrier insulation almost everywhere:
- under roof shingles
- under floors
- under stucco in exterior walls
- inside walls, just behind drywall
- inside basement walls, just behind finish
Radiant barrier behind stucco has an added benefit: it introduces an air gap between the building structure (sheathing, studs, beams) and the stucco. This air gap reduces heat conduction between the building structure and the outside, effectively increasing the insulation value of the walls. This little bit of insulation makes a big difference in the overall insulation value of the wall because the studs and structure have much lower thermal resistance than a foam-filled stud cavity.
For example, consider a 6 inch wall of R25, whose structure covers 10% of the wall area, and is about R6. The wall has an effective R value of R = 1/(0.9*25 + 0.1*6) = R19. If the bubble adds R3.8 everywhere, then the wall's effective R value becomes R = 1/(0.9*(1/(25+3.8)) + 0.1*(1/(6+3.8))) = R24. So adding 1/4 inch of bubble increased the real R value of the entire wall by 20%!
Radiant barrier was the first insulation installed in the second floor of the house, prior to new roof shingles, in mid-summer. The difference was immediate and noticeable. The temperature in the second story dropped 15F, and it was cooler upstairs than it was outside - with no other insulation in place!
Icycene blown-in insulation
The bulk of the insulation is blown-in Icynene. Blown-in insulation does a great job filling areas between wires and pipes, and has no problems filling odd cavities where standard batts of insulation would need to be crammed in (poor insulation) or leave voids (no insulation). Spray-in practically eliminates drafts through walls and ceilings, and thereby substantially reduces problems associated with vapor permeating walls with its resulting condensation.
Rigid Foam Insulation
Rigid foam insulation is used where few interferences exisit: under floors above crawl spaces, under tiles floors over slab, and as insulation in basement walls. Under wood floors in the joist spaces, 3" thickness Dow Thermax board with radiant barrier is used. Its radiant barrier reflects heat back up to the radiant floors. Thinner 1" thickness Dow Styrofoam blue board in combination with CBF Ultra radiant barrier is used over slab floors and behind basement walls.
Fiberglass batts are used to fill larger dead spaces that don't have wiring or plumbing in them, such as cavities under roof walls.