I’m getting ready to gut and insulate a room in my 110yr house on Long Island NY. I want to go with a DIY spray foam kit like Tigerfoam. I don’t want to glue my sheathing together making repairs later impossible, and I’ve heard it is good to leave an airspace behind the sheathing on an old house (siding is cedar clapboard) So I was thinking of leaving a 3/4″ airspace with some 1.5″ Tuff-R polyiso boards cut to fit into the stud bay, then spraying it with the foam the rest of the way. Going to cover it with 5/8″ rock. good/bad Idea? Thanks Mike
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I don't like spray foam. I
I don't like spray foam. I will advise you that you don't need a space.
If you saw the retro foam from the 70's you will understand my scepticism. I just have a hard time believing that site foam is as carefully controlled as the foam in a factory.
My preference is cellulose.
I was considering wet spray cellulose, but there doesn't seem to be any rental possibilities for the sprayer.
Mike
Just run strips of tar paper on the back of the siding stapled out an inch or so onto the studs and tuck it down over the bottom plate and sill to the bottom of the siding (generally requires removing the siding at the rim joist only) then make sure your foam guy picture frames the foam to glue the tar paper to the studs before he sprays the middle of the paper to fill the wall.
And get a few prices from your local Demelec and Icenene guys on installing the foam from the big expensive truck to see if it's more or less expensive than buying the tiger foam and doing it yourself. I'd bet it's cheaper to let someone else do it for you.
Sort of a belt-and-suspenders partial felt retrofit?
I don't know about the tar
I don't know about the tar paper, If I was going to use a flexible barrier I'd staple in some R-Foil and spray against it. I stll like the idea of the Tuff-R board.
The room is small, I've got 134sf of wall area, together with the ceiling a 600bd ft kit ($600.00) should be enough. The Icenene guy with his 100k truck, insurance, overhead etc is going to want at least that just to show up.