# My Rim Joist Air Sealing Fun...



## collegetry (Feb 7, 2012)

You should seal that hole with something. And it's too bad the builder did not lay down sill plate seal between the sill plate and the foundation wall.


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## HDS (Jun 21, 2014)

Will definitely seal up the hole, thinking some 1/4" ply with caulking all around, followed up with the rigid foam caulked in place for air sealing and insulation value. 

The top of the foundation wall is just plain nasty with dirt and most likely mouse droppings as we have had some issues with them. I sprayed the top down with diluted bleach and was using disinfecting wipes to wipe it all up, but there is so much crap there not sure how to handle it all. 

I know you aren't supposed to use a vacuum, but maybe a shop vac with a hepa filter?


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## Windows on Wash (Aug 30, 2011)

I would tack some plywood in there prior to the rigid foam and sealing.


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## cleveman (Dec 17, 2011)

I use a vac all the time.


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## HDS (Jun 21, 2014)

Got delayed picking up the rigid foam board due to my son coming down with a fever. He's better now but couldn't head out to the insulation supply house.

Used 7/16 osb for the patch, a bead of caulk on the back around the hole, and decking screws to hold it in place. 

Air sealed a few more bays using Alex Fast Dry from DAP.

Will use the PL Premium for the sill plate to foundation sealing. Whatever was used prior is coming off in places so would really like it to stick.

Only 30 more bays to go...


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## Windows on Wash (Aug 30, 2011)

Looking good.

Now insulate with some rigid foam, seal the sill plate to foundation connection, back with batt insulation, and admire your work.


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## TeeRiddle (Oct 21, 2014)

HDS, caulking around the rim joist and sill plate is interesting. Never thought of that.

Could you use spray foam (the Great Stuff kind) to do that, or is caulking better?

Thanks


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## HDS (Jun 21, 2014)

Tee, caulking makes a flatter seal for when I add the rigid foam insulation. The gap between the rim joist and sill plate is pretty small, so it is easier to force cualking into the gap. Plus it is a first line of defense against air infiltration. I'll use great stuff for holding the rigid foam in place as the gaps are much bigger.


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## tbeck3579 (Dec 9, 2014)

Nice job. Can you come to my house when your done? :laughing:


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