The key is to find the main nest. The nest is usually found through inspections and following the ant trails back to their nest. If you see more than 10-12 ants in your house, it is worth investigating whether there is a nest in the house. It is important to identify if is indeed a carpenter ant. Carpenter ants are attracted to sweet food in the early Spring and you may be able to attract the ant and follow its trail back to the nest. Remember, they are mostly active at night. Inspect crawl spaces, and attics as well as under porches. Look for mounds of loose shavings or sawdust beneath a crack in the wall or eave space. Carpenter ants particularly like to nest in wall cavities, under sidings, between floors and where wood is in contact with soil.
It is important to identify the ant and locate the colony. Outdoor colonies and indoor ants can be treated with baits or drenching the nest with a properly labeled pesticide and a compressed air tank sprayer.
Make physical changes necessary to repel the infestation (Seal cracks and crevices where the insect swarms enough).