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What are these ants in my upstairs bathroom?

Question: I live in Leesburg, and have been seeing tons of large black ants in my upstairs bathroom. I don’t see them anywhere else in my house. Where are they coming from? Why are they there?


While it’s impossible to answer your question conclusively without a thorough inspection, it sounds from your description like you have carpenter ants.

It’s not uncommon for people to have your experience – finding these particular ants only in the bathroom, and often upstairs. That’s because carpenter ants love nesting in moist wood. The fact that you’re seeing them in your bathroom could indicate a leak or improper drainage around your sink or bathtub, though the problem could just as easily be a poorly-sealed window frame. Carpenter ants have also been known to nest in the dampened wood around door frames, wooden porches, roofs, and gutters.

Carpenter ants are different than termites in that they don’t eat the wood. Instead, they use their sharp mandibles to hollow out damp wood for nesting. Evidence of their smooth, sandpaper galleries is often seen in the form of wood shavings and dead, half-eaten insects around the nesting area. You may not be seeing any of these signs, however, if they are concealed behind the wall or in another hidden nook of your home.

Luckily for you, carpenter ants also don’t cause nearly as much structural damage as termites, as they only remove as much wood as they need for a nest. However, they do have the potential to weaken studs and other structural timbers. If you’re worried about damage, or simply want to locate the nest and eradicate the colony, it’s usually best to contact a professional. They can also let you know whether your infestation is a sign of a bigger problem.

Carpenter ants are often found upstairs due to tree limbs and branches that are touching your house and acting as a bridge into your home. Consider trimming any such branches away, as well as sealing up cracks and openings, fixing any leaks, and stacking firewood away from your home.

Green Pest Services can help you find the source of your ant problem and take steps to free your bathroom of carpenter ants once and for all. Contact us today for a consultation.