Great stuff spray sealant between tile floor and wall moulding

[Clarence Martin]

Need to seal up some gaps in the wall between the tile floor in the bathroom and where the wall mounding meets the floor. The floor is not level, it dips a bit in one spot, so there is a gap in the middle of the floor under the molding. Last night , while in the bath tub, I noticed a HUGE!!! black spider crawl out from the wall. Will that spray foam sealant keep those things out ??????

[Mike Schuch]

When I replaced every floor throughout my house I used great stuff in all the voids between the flooring and the studs under the sheet rock. The best part is that the foam is easily compressible so it won't cause a floating floor to buckle. I think it is particularly good for bathrooms because it contains and water spills.

[Jerry Miner]

That stuff expands like crazy and will make a huge mess. I would use a good latex acrylic caulk. Anything that seals the gap will keep the critters from crawling through.

[Mike Schuch]

That stuff expands like crazy and will make a huge mess. I would use a good latex acrylic caulk. Anything that seals the gap will keep the critters from crawling through.

Just spray it sparingly then trim is with a Japanese flush cut saw before putting on the molding. But since the molding is already up in your bathroom latex or silicone caulk would probably give a much nicer finish.

[Jason Roehl]

Just spray it sparingly then trim is with a Japanese flush cut saw before putting on the molding. But since the molding is already up in your bathroom latex or silicone caulk would probably give a much nicer finish.


Silicone caulk has no business anywhere near trim carpentry.

As a (former) painter of 19 years, I encountered this way too much--too often I wanted to take the caulk gun from carpenters and beat them about the head and shoulders with it.

Make sure whatever caulk you use is labeled "Paintable"--typically a good acrylic latex (some will say "siliconized", and that's typically okay, as it's a marketing term and has nothing to do with silicone).

[Peter Quinn]

If the gaps are too large caulk may sag and fail, you might try using backer rod before the caulk, or use backer rod then add a shoe molding. I'd use the spray foam only if you absolutely don't care how it looks when finished. Expanding foam is not a precision instrument, if you feel you must use perhaps stick to the lower expanding door and window foam instead of the 3x high expanding foam.

[Jim Dwight]

I like "Duo-sil" urethane caulk. It's paintable but doesn't need paint over it to maintain it's color and not fall apart from UV. You have to find a builders supply place that handles it but if you do, it is not terribly expensive. The last I bought was about $3/tube. It's about as flexibile as silicone but without the paintability issues.

If you need to do a lot of expanding foam sealing or if you just want to do it with less mess, the $50 gun works a lot nicer than the $5 cans. You can use a can over and over again with the good gun. You can also control the bead a lot better. I have to cut the residue off the tip and then I can just spray a little or a lot. When you release the trigger it seals up and you can put it away for next time. My house has a lot of leaks so I seal them up as I have access. I've used spray foam as a backer for Duo-sil before too. Works fine.