Carpenter ants are NOT sugar ants, the controls are different.


The first thing you want to do is to attempt to locate their nest. This isn't often easy, as the main nest can have several satellite nests. If you manage to find the nest, you need to remove as much of it as you can. It's tough if they've made a home in a structural member, but removal is always the best first step. You also have to check for areas in and around your home where water might accumulate, and fix those areas. A common place for them to hide is behind the gutters, where there are wooden eaves as well as moisture.



As far as chemical controls, carpenter ants have appetite for different things at different times of the year, and depending on their reproductive cycle. Sometimes they go for sweet stuff, sometimes for protein. When they are in their "sweet" cycle, I've found the best product to be Terro ant bait, which can be found at HD. If you can get them to feed off of a Terro trap, the nest will die in a couple of days. If they are in a "protein" cycle, you can try Advance carpenter ant bait. This may not be available for homeowner application, depending on what state you are in.



There are specialized carpenter ant sprays as well. Unfortunately, you would need to saturate your home. A carpenter ant spray is typically applied heavily all around the home just above ground level. They are for outdoor use only, and they are fairly persistent chemicals. Unfortunately, this will have no effect if the ants have found a damp spot at the roof level. In that case, you will need to spray the roof and eaves as well. Sprays are generally less effective than bait traps. Personally, I find it's MUCH preferable to use baits.