Subfloor insulation material?
user-894335
| Posted in Green Products and Materials on
I am building a new house and plan to use Green Fiber cellulose for wall (dense packed) and attic floor (loose) insulation. I was told that cellulose does not work for subfloor insulation. We have raised foundation with 2′ vented crawl space in California.
I don’t mind using fiberglass in closed cavity walls and plan to use it for interior walls for sound barrier. However, I prefer not to use fiberglass for subfloor insulation. Is there any other alternative?
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Replies
Rian,
Some crawl spaces are damp. For that reason, I suggest that you install rigid polyisocyanurate insulation on the underside of your floor joists. Do a good job of air-sealing the polyiso seams, as well as the perimeter of the insulation.
If you feel confident that your crawl space will be dry, you could install dense-packed cellulose in the joist bays above the polyiso. However, since most floor joists include plumbing pipes (with their periodic leaks), there is a certain logic to skipping the cellulose and sticking with polyiso.