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Sealing the house against ants

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May 14, 2013, 11:35 AM
Sealing the house against ants
Carpenter ants in my home have finally taken up residence elsewhere, after a year long battle.

In an interesting twist, it was the advent of the spring rains that caused them to find better quarters. I've also found that a boric acid, sugar and water solution worked better and quicker than commercial pesticides, which I resorted to only in desperation. Perhaps it was the 20 Mules in the borax that stomped the ants to death that caused their demise.

Articles I've read on ants have advised to seal all openings of the house to prevent them from sneaking in. My house is aluminum sided, so I assume that would mean sealing at the base of the siding as well as around any cable and other openings.

When my garage was sided in 2007 the sider told me never to caulk siding. So how can I seal the siding at its base against ants? If I shouldn't caulk it, is there some kind of permeable membrane that I could use? any other advice?

Thanks for any suggestions.
May 14, 2013, 12:00 PM
there may be a place under the lip of the siding where you have access to the foundation and sheathing layers of the wall. caulk that area.

there whould be weeping allowed under the siding itself so water doesn't trap there and eventually work its way through the tarpaper or housewrap. this is what you were told to preserve. the rest is fair game for sealing up.

sig: if this is a new economy, how come they still want my old-fashioned money?
May 14, 2013, 12:09 PM
I'm going to take a look to see what's there. Back later, probably with more questions Smile. Thanks for the reply.
May 14, 2013, 02:59 PM
Carpenter ants like wet wood, if you caulk the bottom of your aluminum siding you run the risk of holding water in behind the siding.

Are you sure these are carpenter ants which are quite large and munch on the wood structure of the house.

General Disclaimer

Any advice given here is general in nature and is not necessarily valid for your given area. If in doubt check with your local codes enforcement department for what is required when doing electrical, plumbing or structural work on your house. Permits may or may not be required in your area and home owners may not be able to DIY some tasks. I have no way of knowing if you have the skills needed to complete the tasks you are asking about, when in doubt seek professional assistance.

My advice may be worth exactly what you pay me for it. :-) For the record I did not stay in a Holiday Inn Express last night.
May 14, 2013, 04:24 PM
I would seal the open areas with bronze or stainless steel wool . this would allow moisture to escape but keep other critters as well as ants out. google bronze wool for sources
May 14, 2013, 05:32 PM
Sparky, I'm pretty sure they're carpenter ants. I've been watching and swatting them for 13 months now! But there could also be a mixture of carpenter and some other kind of ants.

There are different sizes: Smallest ones are about 1/4" long, so they could be some other kind of ants, but I believe they're the smaller size (minor) workers. Most of the ants are about 1/2" long and well rounded and well nourished, kind of plump. These two sizes are typically energetic except for the first few days after new bait is set out.

The winged (reproductive) ants are about 5/8" to 3/4" long. Their behavior is slightly different. Most frequently they're slower and sometimes sluggish, but on a few occasions they're quite energetic.

In this photo, I have ants like the queen, the major, intermediate and sometimes smaller workers. I've never seen winged male ants. The ants in the photo are just a fraction larger than mine; I think the photo is a little larger than the actual ants.

From what I've found, the two larger sizes are characteristic of carpenter ants.

They've also been in the doors, initially two doors. I discovered them when I heard strange noises in the bedroom door and subsequently found they were in the bedroom closet door as well. When I then checked other doors, I found them in the study closet door.

Using a stethoscope against the door, I coud hear activity inside. I've also found them in the overflow hole of the bathroom sink and the bathtub. They're not in the kitchen though. The tiny, tiny ants have been there but I got rid of them very quickly with a borax solution. Best thing I ever used on ants.

I've tried a few different methods of luring the bedroom ants to locations where I could more easily dispose of them. If there's a little bit of water around the drain of the bathroom sink, or on the sink, I'll find about a dozen of the 1/2" ones about 6 am the next morning. It's clear they're attracted to the bathroom.

There's a pattern to their response to chemical bait. First the smaller ones and/or or the 3/8" ones appear. Anywhere from a few days to a week or so later the winged ones appear. After several weeks, the number of ants decreases and the cycle starts over again when I put out fresh bait.

The side of the house in which I've found the most ants has a 4' setback, and right next to the 4' border is a big pile of brush which for some reason the neighbor has been accumulating. I've asked them to clear out the pile and gradually it's decreasing.

There is some wet wood in the house, and I'm working on resolving that, but in the meantime would like to seal them out in the event we have a drought and they decide to return.

Nona, I googled bronze wool and it sounds better than steel wool as it doesn't rust. I'm searching now to find locations.

Thanks to each of you who responded.
May 14, 2013, 06:40 PM
A good 100% identification of carpenter ants is to see if they have those itty-bity leather tool belts on. A sure sign of a carpenter ant.

I think the best approach is the aggressive poison use - especially the type that they can carry back to the nest and feed to others. As a builder, I do not believe that it is possible to seal a house against insects (for that matter, mice too). Houses will move, expand and contract and have way too many hidden areas that critters will be able to find and you will never locate.

When I built my house, I decided to make it critter proof. I sealed under all bottom wall plates, sealed the entire house - walls and ceilings with plastic and made sure that everything was tight. I actually had to undo some stuff later on, as the house was so airtight that if I quickly closed the front door it would suck the upstairs French doors in the master bedroom open.

But back to the critters. Even before we moved in we got mice. Lots of them. Pretty sure they found some remote place around plumbing or ductwork.

May 14, 2013, 10:02 PM
Originally posted by Jaybee:

A good 100% identification of carpenter ants is to see if they have those itty-bity leather tool belts on. A sure sign of a carpenter ant.

Well, I tried to pick one up sometime ago to check it out and it bit me. Felt like a yellow jacket sting. Nasty tempered little thing.

Guess I better find a stable for the 20 mules; they do the best job of wiping out the ants. Not crazy about all the braying though.