Insulating a Crawlspace with Rubber Mats
handymanjohnny
| Posted in General Questions on
dear reader do you think it would be a good ideal if i insulated my concrete craw space with 6 mil vapor barrier and then 3/4 inch 4f by 3f recycled rubber mat on top of vapor to cut down the moister or humidity
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There isn't a lot of insulation value to rubber matts. You're probably looking at R1.5 best case, not more.
That said, installing it on the crawlspace floor or walls doesn't do any harm. Putting real insulation on the crawlspace walls and the rubber mats on the floor makes it more comfortable to work in there when any plumbing or electrical in that space needs servicing. Putting it on the floor over a vapor barrier also protects the vapor barrier from damage.
What IECC climate zone are you located in?
my ideal was to use the 3/4 inch rubber mat on the concrete floor rather then the Subfloor Membrane Panel 3/4 in. x 2 ft. x 2 ft. Oriented Strand Board that they sell at home depot which really is a dip plastic or pvc glued to a osb plywood which i think would be even less r value then the 3/4 rubber also if i ever got water in the basement the rubber wood withstand it i would think. and 2 inch Styrofoam ins on the walls. i live in watertown NY
I would expect those rubber mats to be pretty impervious to moisture and even bulk water. If you're OK with those as a flooring material, I'd expect them to last a pretty long time in your application. You won't get a lot of R value as Dana mentioned, but you'll have something durable that won't care about water and that's important too.
I would use regular rigid foam on the walls. Sounds like you're thinking of using EPS ("Styrofoam"). I'd try to get type-II EPS which is easy to work with since it's less crumbly. If you're thinking of Styrofoam BRAND XPS, I'd reconsider as XPS is less green than EPS and doesn't really have much in the way of advantages over EPS in your application. Since you're concerned about water, I'm thinking you may have had issues in the past so polyiso might not be as a good of an option for you. Polyiso would gain you a bit more R per inch, but it has issues if it gets exposed to water (like a flooded basement).
Bill
Polystyrene foam (XPS or EPS) on the walls needs to be covered for fire protection. One advantage of polyiso is that it doesn't need to be covered.
the reason i thought 3/4 inch rubber would be my best choice is because a friend of myn had used for his basement floor, the Subfloor Membrane Panel 3/4 in. x 2 ft. x 2 ft. Board that they sell at home depot which is only a obs plywood glued to a thin piece of dipped pvc and he put a vinyl laminate on top of that and i find it to be cool so i thought i should do my basement a little different by maybe putting down a vapor plastic then 3/4 inch rubber mat on top and then a vinyl floor what do you think about that ideal