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Community and Q&A

Installation of off-size reclaimed foam

Jim Tyler | Posted in Green Building Techniques on

I’m trying to get my hands on recycled foam for a REMOTE wall home build. I have a potential supplier with enough brand new EPS to do my project…but it’s in 8′ x 19.5″ and 8′ x 9.5″ sheets – all 3″ thick. Brand new, so I can count on clean edges.

There are enough of the 9.5″ sheets to do my basement walls.

There are enough of the 19.5″ sheets to do my exterior walls.

My questions:

In the basement, I don’t see a big loss in going with the small sheets. Adhere them to the walls and stick frame inside them just like I would with full sheets. Am I underestimating how much of an R value hit I’ll take with so many seams between panels? Am I underestimating or neglecting any other considerations / expenses?

On the exterior walls…different story. I haven’t done the math yet, but off the top of my head it’s ~ 2x the tape and a lot more screws. What other issues have I not considered? Installation and expense issues, but also – maybe more importantly – is it in any way a performance downgrade to switch to sheets this size?

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  1. GBA Editor
    Martin Holladay | | #1

    I think that you have summarized the issues adequately. There will be higher expenses for canned spray foam and tape -- but if you are conscientious, I think that you can get a high-quality result.

  2. Joe Suhrada | | #2

    This isn't the stuff from the chicken coops again is it?

  3. Jim Tyler | | #3

    The supplier said "brand new," so I think I'm safe. I don't think the line between "brand new" and "used to insulate a chicken barn" is thin enough to get that blurry. You did scare me enough to do a search though...the chicken barn stuff was 1.5" XPS in 4' x 21' sheets.

    Thanks for the input, Martin. I did some quick calculations on tape and spray foam, and I have a couple ideas about ways to get things tacked up without buying more screws. I'll be back with questions if things go sideways...or if my house smells like chickens.

  4. Michael Grundvig | | #4

    Yeah, that used foam has proven to be my biggest mistake on the house build thus far. Leaving it in the sun did nothing for the smell. The weather has been a bit too rough for us to try the other two proposed cleaning options. I'm badly regretting going used foam all around right now.

  5. Joe Suhrada | | #5

    Michael, I know my answer was tongue in cheek on that thread but can't you bury it as exterior basement wall insulation. I am certain that you will never smell it under the soil as the microbes which eat oil, gas, dead bodies and dinosaurs and render them to nothingness will certainly kibosh the stink. The earth is the most powerful of all cleaners. That is a lot of shovel work perhaps but it can all go under grade and you can at least get some use from it. We had poor Jim very concerned. Sorry, Jim. The odd size grabbed my attention.

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