I currently have pink fiberglass insulation stuffed into the rim joists in the basement. I want to remove and replace the insulation.

I was thinking of using a DIY spray foam kit like Tiger Foam which would be around $600. Im not sure if the ease of use vs. desired results will be there. It would take multiple passes to gain the required depth to fill the joists.

Replacing with pink fiberglass would be the safest bet and the lowest cost.

Would there be that much of a benefit to using the spray foam?

This message has been edited. Last edited by: gpbst3,

I packed cement / concrete into joist pockets. On some of them I bricked up and cemented the entire bay above the foundation wall.

Spray foam will not stop rodents, I believe. They've even chewed through stainless flex duct.

A few bags of steel wool pads from a restaurant supply would be fast and cheap. Rule of thumb is no hole bigger than a dime although on a recent restoration I sealed to within a 1/4" to pipes.

You need to find where the rodents are getting in at seal it off with metal screening or something else first they cannot penetrate.

There are basically two types of foam to my knowledge, Two Types of Spray Foam Insulation Closed Cell and Open Cell. Closed Cell will repel water while Open Cell will act like a sponge. Most, if not all, of the do-it-yourself stuff it open cell foam. Foam is wonderful stuff if used correctly. Also, look for foam that is fire retardant.

Personally, I'd hire a pro to make sure the foam is properly mixed and with some foams, they are not intended for the do-it-yourselfer. You are not dealing with a can of Great-Stuff.

Updated: there is no current rodent issue. Im more concerned about what insulation to use.

Spray foam is what you want to use if you're looking to completely air seal your house at the rim joist and sill plate. You will want to spray from the subfloor, down the rim joist, across the sill plate, and overlap the foundation wall.

I used a kit from Menards to do mine: https://www.menards.com/main/p...9717732546136&ipos=6


You do not have to use the spray foam to get to your insulation value. You can use it to seal everything, and then add fiberglass over it to achieve your end result. I also used 2" XPS foam on the foundation wall.

quote:

Originally posted by gpbst3:
Updated: there is no current rodent issue. Im more concerned about what insulation to use.

Check local code. Here in Michigan the inside face of rim joist insulation must be fire-retardant/-resistant.

We had a rodent problem due to a gap just big enough for them in one corner. I sealed it up with Great Stuff Pestblock. The rodents never came through there again.

After I assured myself that did the trick for the rodents, I sealed all seams/joints with more Great Stuff, carefully trimmed the excess, then glued-up three courses of rigid foam insulation. The first course had a 1/8 in. or so gap all around, which was then filled with Great Stuff. That formed an air- and moisture-tight barrier. The second course of the same stuff was fit snugly over that. The last course was one inch foil-backed rigid foam, foil facing in, also fit snugly.

Yeah: I didn't fool around

If you are going to use anything like Great Stuff, do yourself a favor and get the contractor’s gun. The foam is cheaper in the contractor cans, and you can start/stop a can.

Rigid foam insulation with great stuff around the perimeter is much better than batt insulation. The foam provides a vapor barrier and stops the air flow you have with batt.

I did buy basement sills with rigid foam board and spray form. Made a template and then cut out with a razor knife. I then sprayed around the edges with spray foam.

You cut a bunch of pieces, they go to town spraying the edges. Worked great.

quote:

Originally posted by Baran:
I did buy basement sills with rigid foam board and spray form. Made a template and then cut out with a razor knife. I then sprayed around the edges with spray foam.

You cut a bunch of pieces, they go to town spraying the edges. Worked great.

Did you do one layer of foam board? I would think I would need multiple layers to equal the pink stuff.

quote:

Originally posted by mark60:
Rigid foam insulation with great stuff around the perimeter is much better than batt insulation. The foam provides a vapor barrier and stops the air flow you have with batt.

This is what I did. I did two layers of rigid.

I paid someone to spray mine. One of the best upgrades to my house I ever did.

My ROI was about 2 years savings in heating cost.

I sprayed my first floor, floor and walls.