Minding the gap

July 6, 2009 8:36 AM

Best way to seal tiny gaps between the hardwood floors and the baseboards?

Ants are coming in through the gaps. What compound should I use to seal off the openings?

posted by Mountain Goatse to Home & Garden (14 answers total)

You can use caulk. They even have painter's caulk if you need to be able to paint whatever you're caulking later.
posted by scarykarrey at 8:38 AM on July 6, 2009

Great Stuff comes in a variety of expansion styles and can be found at any home improvement store. Get the minimally expanding foam, otherwise it'll pop your base boards off.

Knock the excess off with a utility knife or wire brush. You can paint or seal over it if you don't like the color.
posted by wfrgms at 8:38 AM on July 6, 2009 [1 favorite]

Be very careful if using GreatStuff. As the building expands and contracts or different materials adjust to varrying temperatures and humidity you will find the gaps open and close. Therefore, use something such as caulk that allows the materials to flex. Even the low-expanding version of GreatStuff doesn't flex like caulk.

And, with ants, the problem is that when you seal one entry, they often find another if there is something which attracts them on the inside. Consider attacking the insect issue as part of your remedy.
posted by mightshould at 8:48 AM on July 6, 2009

If you have white baseboards, caulk would look okay, but I think it would look pretty odd to have a strip of rubbery caulk between a wood-grained baseboard and a wood floor. Even if it was brown caulk.

I would probably concentrate on sealing up the exterior of your house, as well as spraying the foundation.

If you want to apply caulk inside, you should be able to take a small pry bar and start at one end of the baseboard, pry it off gradually at each point where it's nailed. Once it's off you can really seal up the gap between the drywall and the floor. This would also be a good time to paint or to refinish the baseboards if you are so inclined. Then, just nail the baseboards back up. Countersink the nails and fill in with matching wood putty.

Great Stuff is not easily controlled and it would make a huge mess. You needs something with more precise control for that tiny gap.
posted by Ostara at 9:22 AM on July 6, 2009

As a temporary and easy solution you can use duct tape. It is ugly but it works. I put it down and then took it off a month later after the ants had gone for good--of course, I had exactly the same issue that mightshould mentioned, when I covered the gaps they just came in another way.
posted by phoenixy at 9:31 AM on July 6, 2009

Try blue painter's tape instead of duct tape, it won't pull off paint or leave residue.

Try sprinkling boric acid around the edges of the room, it's said to repel bugs.
posted by mareli at 9:41 AM on July 6, 2009

There is clear caulk if white won't work.

I have had no luck with boric acid and ant traps haven't been terrifically effective. I've just had to become manic about wiping up crumbs/drips in the areas where the ants seem to want to go.
posted by lakeroon at 10:06 AM on July 6, 2009

Do you have a basement or crawlspace that you can get into to see where the ants are coming in? They're pretty good at finding ways around caulk, so you may have more success heading them off before they enter the house.
posted by orme at 10:14 AM on July 6, 2009

Response by poster: Thanks for all the answers, everyone. These are those hell-spawned argentine ants, and they are just sort of wandering around our bedrooms (no food crumbs or water or anything around).

I'm tempted to put out some Terro, but I tried it outside and it wasn't terribly effective. Sure, they swarm it and eat it up, but the horde doesn't seem to let up even after several weeks of application.
posted by Mountain Goatse at 10:20 AM on July 6, 2009

Go with that lite-expanding foam. I used that and it worked like a charm.
posted by heather-b at 10:36 AM on July 6, 2009

A small teacup-saucer holding a mix of 50% Borax and 50% powdered sugar got rid of our ant problem. The ants carry both sugar and soap back to the nest and the soap poisons the colony.

Like you, we considered caulking the baseboards, but this was a much easier and cleaner solution. The ants do all the dirty work.
posted by baltimoretim at 10:51 AM on July 6, 2009

We've tried all the natural stuff - even salt around the perimeter. It may have helped somewhat, but it wasn't all that useful. We also tried using a bait we discovered that was in a syringe. We "caulked" all the gaps, but the ants seemed to fiind another way inside.

It seems that the best luck we had was with the bait traps that have both sweet and savory baits since we couldn't find anything that was an obvious attractant. It took several weeks, but eventually the bait worked, or they just gave up. Oddly enough, we never, ever saw an ant in the bait - maybe it was simply an effective talisman.
posted by mightshould at 11:04 AM on July 6, 2009

Sealing the gap won't really solve the ant problem. As mightshould mentioned, they will find another way in. If you're in a single family dwelling, I'd go to home depot and get the pesticide that you spray around the foundation of your house. I think its meant to be a once or twice a year application. If you have small pets, look at the bottle to determine if this will harm them in anyway.

Caulk is meant to be an aesthetic, finishing process, and not meant to mitigate insect, rodent or moisture issues.
posted by premortem at 11:14 AM on July 6, 2009

The previous owner of my house stuffed all the gaps with either steel wool or aluminum foil. It seems to work pretty well, but you'd obviously need to cover it up for aesthetic reasons. Do you have shoe molding at the bottom of the baseboards or no?
posted by electroboy at 11:23 AM on July 6, 2009