# spray foam in gap behind baseboards?



## aaronestes

Hello, this is my first post.

My wife and I bought a great little 62 year old craftsmen home about a year ago.  First thing we did when we got in was pull all the carpet and refinish the red oak floors.  Now I'm putting in mdf baseboards and oak shoe molding.

Anyway, my question is this:

As one would expect, there is a gap between the bottom of the wall and the oak floor.  In most areas I can see subfloor (looks like 2x12s running diagonal) in the gaps just past where the oak floor ends.  And in a few spots I can see dirt foundation through the gaps in the subfloor boards.  Hopefully this makes sense.  I was wondering if it would do any harm to spray expanding foam in the wall/floor gaps.  Something like "great stuff".

Thanks
-AE


----------



## Cork-Guy

Personally, I don't see the harm; however, is it possible you can post a picture of this gap? Remember, great stuff is easy to spray on, next to impossible to remove; think about this for future renovations. Why not get some fiberglass insulation?


----------



## budro

cork guy is right. why don't you stash a little insulation in the cracks. spray foam is messy. there also are two kinds. expanding and non-expanding. get the non-expanding kind and be prepared to clean up before you start. best bet on insulation, buy the cheapest roll of insulation you can. use what little you need and roll the rest out in the attic or wherever it could be of help. a house needs to breathe too. i may get an argument here but years ago the veterans administration came to us and wanted us to start wrapping our studs walls with visqueen before we hung the rock. after about ten houses they came back and said "whoa!" it seems we then had them so tight they were sweating at the windows and v.a. had to put dehumidifyers in the houses with visqueen over the studs. your problem probably doesn't need drastic attention but would help some. caulking might do the trick too if your holes are not that big.  budro


----------



## Nestor_Kelebay

Aaronestes:

I agree with the other posters that you'd likely regret putting expanding foam insulation in there because you'd be likely to get it all over everything, including on your refinished hardwood floor.  It's a fight working with that stuff.

What you DO want to do is get something thin and maneuverable, like a hack saw blade, and a strong vaccuum cleaner and vaccuum the dust out of those gaps as well as you can.  The reason why is that dust is 90 percent organic matter, and consists of dead skin cells, cloth and paper fibers, plant pollen and road grit that gets carried into those inaccessible crevices by air currents.  Bugs like silverfish eat that stuff.

It's easy to remove dust from the readily accessible areas of your house, but now that you have access to some inaccessible areas, take the time to remove the dust there so that your house will have less dust in it and therefore can't support as many bugs.  Some bugs feed on other bugs, so the fewer bugs you have, the fewer spider webs you'll have in your house as well.

What you might want to do is buy something called "Foam Backer Rod" which comes in diameters in 1/8 inch increments from 1/4 inch to 1 inch.  You should be able to buy foam backer rod at your local Home Depot or Lowes, but you're paying for the packaging in retail stores.  If you go to any of the places listed in your Yellow Pages phone directory under "Caulking and Caulking Supplies" or "Construction Materials", many of them will likely sell/give you as much foam backer rod as you need if you contribute $5  toward their Staff Christmas Party Fund.  (It's quite inexpensive.)

You use the diameter of foam backer rod that's just a little larger than the gap you want to fill.  So, if the gap under your wall is 1/4 inch, stuff 3/8 inch diameter foam backer rod into it.  Not only will it push in easily, you can remove it easily should you ever need/want to.  







After removing the dust, stuff foam backer rod under your walls.  It'll prevent drafts, insulate a bit and keep the outdoor bugs from consorting with the indoor bugs of your house.

Or, if it wuz me, I'd be more inclined to use foam backer rod than either expanding foam or caulk.


----------



## handyguys

I wouldnt worry about it at all unless its a bit drafty. I like nestors thought of running the shop-vac before proceeding. If I were to do anything I too would just use fiberglass. and stuff it in the space. Use a putty knife to push it in. 

I got an email from someone who got greatstuff on newly refinished floors. Lets just say the fix was not to his liking. Stay away from it for this project.


----------

