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Deb
Sill Plate - Please Help

I have read and read, and still am not sure how to do this.
1940's clapboard, framed 12" centers, on block, In pennsylvania. The plan is to sheet rock ceiling and interior wall in part of the basement (which is dry, thank God) for teenagers & ping pong. Exterior wall is dry locked, painted, Mostly in closets. Rest of exterior wall & heat will be done when $$ allows. I want to insulate at least the sill plate / rim joists before sheet rock is put on ceiling of basement. Not sure how to do the sill plate, what's the best to use (No P2000 referals please) and do I need a vapor barrier??? PLEASE advise :eek:

JLMCDANIEL
Re: Sill Plate - Please Help

Deb, I would recommend you consider DIY spray foam, one supplier Foam it Green even has a video and a Project Estimator. This is one of the best and easiest ways to handle the sill plate/rim joist areas.

Jack

Re: Sill Plate - Please Help

Use poly foam backer rod-its cleaner than expanding yellow stuff and it will flex, jam it in with a putty knife. and it will stop infiltration.

canuk
Re: Sill Plate - Please Help

Deb ... you can seal the sill plate with caulk , spray foam or the backer rod to prevent air infiltration.

Then you can install insulation to the rim joist.
The trick will be installing the insulation ensuring it is air tight. The reason is to prevent warm moist air from the living space getting in behind the insulation and contacting the cold surface of the rim joist .... that will cause condensation ( moisture issues) .

As for types of insulation you can use batt or rigid foam.

With the batt you will require a vapor barrier. If you use the unfaced batt then use a plastic vapor barrier over this on the room side. It will need to be sealed so air won't get in behind. You can use an acoustical sealant caulk that we use up here all the time for sealing vapor barriers.

If you use the paper faced insulation ensure the paper is facing the room side. this type is more difficult to ensure an air tight seal

With the rigid foam you won't require an additional vapor barrier applied though it is a good idea to completely caulk all the edges of the foam to ensure no air gets in behind.

A couple of examples ... the pix with D. Duck is faced batt insulation
the other is with rigid foam .... hard to see ... it's the white stuff

Hope this helps. :)

Deb
Re: Sill Plate - Please Help

The second picture has me confused. The white is rigid foam board, what is the gray? Spray foam ? what is the "This Side" board? Mine does not look like that, my 1st floor boards sit right on top of joists, there are no spaces. Sorry if I'm being a flake. Here's what mine looks like now, there is an old gray painted trim piece in front of the sill, this I guess I should caulk behind & under.

Attachment: 
Blue RidgeParkway
Re: Sill Plate - Please Help

guessing that gray on the joists is galv joist hangers mabe some sort of thing on either side of bolts from foundation to sill plate? mabe the ridgid foam is the gray between the joists or is that concrete? just above the telephone line and the white above and behind it is spray foam? hard to tell looks wet. looking forward to the reply on that.

canuk
Re: Sill Plate - Please Help
Deb wrote:

The second picture has me confused. The white is rigid foam board, what is the gray? Spray foam ?

The white is the rigid foam.
The gray is just concrete in this case.

Quote:

what is the "This Side" board? Mine does not look like that, my 1st floor boards sit right on top of joists, there are no spaces. Sorry if I'm being a flake.

This is from a a more modern built home using plywood for the subfloor instaed of planks.
That marking is to indicate which side goes down.

canuk
Re: Sill Plate - Please Help
Blue RidgeParkway wrote:

guessing that gray on the joists is galv joist hangers mabe some sort of thing on either side of bolts from foundation to sill plate?

Incorrect.
The grey is concrete.

Quote:

mabe the ridgid foam is the gray between the joists or is that concrete? just above the telephone line and the white above and behind it is spray foam? hard to tell looks wet. looking forward to the reply on that.

Nope.

The grey is concrete.

The white is rigid foam.

canuk
Re: Sill Plate - Please Help
Deb wrote:

Here's what mine looks like now,

The first pix with D. Duck is a similar construction to yours.

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