insultating rim joists, redux
#11
  Re: (...)
the 1st floor joists in my house are 16" on center. So at both ends, the rim joists are really hard to get to. I'm thinking on the chimney end, the only way I'm going to be able to insulate those cavities is using foam. I doubt someone is going to want to come in and do 8'x16" worth of foam. The boxes of foam scare me a little. I know some people on here have used them. Is spraying blind into a cavity like that going to work? The opening is almost exactly filled with a 2x4 (1.5 high, 3.5 wide)
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#12
  Re: insultating rim joists, redux by EricU (the 1st floor joists...)
They have a wand tip to inject the foam deep into a recess. You have to be aware of foam expansion issues though.
WoodNET... the new safespace
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#13
  Re: insultating rim joists, redux by EricU (the 1st floor joists...)
Foam is combustible. You don't want it touching your chimney. Code says 2" air space. In that air space I stuffed kaowool and then smeared firesafe caulk over it for an air seal.
Matt

If trees could scream, would we be so cavalier about cutting them down? We might, if they screamed all the time, for no good reason.
-Jack Handy

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#14
  Re: Re: insultating rim joists, redux by EatenByLimestone (Foam is combustible....)
thanks, hadn't thought about the chimney
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#15
  Re: Re: insultating rim joists, redux by EricU (thanks, hadn't thoug...)
If the house is ever sold and there is exposed spray foam, the inspector will note it on his report as a possible fire/safety hazard. Just like exposed foam board. There is nothing wrong with it if it is covered with sheetrock, or even plywood.

Some foams claim to be fire retardant and they may be but the inspector won't make that determination.
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#16
  Re: Re: insultating rim joists, redux by Snipe Hunter (If the house is ever...)
Snipe Hunter said:


If the house is ever sold and there is exposed spray foam, the inspector will note it on his report as a possible fire/safety hazard. Just like exposed foam board. There is nothing wrong with it if it is covered with sheetrock, or even plywood.

Some foams claim to be fire retardant and they may be but the inspector won't make that determination.




So I am also doing this with foam board. No chiminy to worry about. I dont have plans to refinish the basement at the moment. Originally it had the fiberglass mats stuffed in there, and I still have those pieces. Do I need to put them back in front of the foam board?
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#17
  Re: Re: insultating rim joists, redux by Snipe Hunter (If the house is ever...)
I'm putting the ceiling back up in this particular area, so no problem with that. I think I've heard of people putting drywall up to hide the rim joist foam insulation. I have one section of the basement with dropped ceiling, so I need to worry about fire in that part. I was thinking about using the fire rated foam board with aluminum facing, but since there will be foam around the edges, drywall will probably be better.
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#18
  Re: insultating rim joists, redux by EricU (the 1st floor joists...)
" insultating rim joists" I talk to mine in a polite manner right up until they give me trouble and then the insults fly
Phydeaux said "Loving your enemy and doing good for those that hurt you does not preclude killing them if they make that necessary."


Phil Thien

women have trouble understanding Trump's MAGA theme because they had so little involvement in making America great the first time around.

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#19
  Re: Re:, redux by Bob10 (" insultating rim jo...)
haha Bob, I didn't even notice that. I just switched to a wireless keyboard, and things ain't going in my favor. I used to use an IBM type M, so everything is a downgrade. I might have to get one of the modern type M keyboards with usb.

I try not to insultate anything like a water heater or a refrigerator that can get back at me. I'm hoping the rim joists can be big about it.
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#20
  Re: Re:, redux by EricU (haha Bob, I didn't e...)
watch your step

Phydeaux said "Loving your enemy and doing good for those that hurt you does not preclude killing them if they make that necessary."


Phil Thien

women have trouble understanding Trump's MAGA theme because they had so little involvement in making America great the first time around.

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