Most ants choose to make their homes in the ground. Certain ants, such as thief ants, pharaoh ants, carpenter ants and odorous black ants are known to build their nests in walls. Carpenter ants, for example, burrow through wood to make their homes, and this burrowing can destroy the structural integrity of your home. Treating wall-dwelling ants quickly and effectively can help save your home from damage. Although you could use a commercial ant treatment, those can be expensive. Killing the ants yourself is less expensive and requires little effort.
Mix together one part honey and one part water in a small bowl. Stir the contents to combine. If the honey is particularly thick and difficult to mix with the water, microwave it for 5 seconds to soften it.
Place a piece of tape in a location where you have noticed high ant traffic. Place the sticky side of the tape down. The purpose of the tape is to give you a location to apply your bait that will stay put and provide easy clean up.
Apply a drop or two of your honey and water mixture onto the tape. The honey will attract the ants. Watch for the ants to come to the honey and carry it back to their nest. Follow the ants until they enter a wall. This place likely is their nest site.
Use a drill equipped with a 1/8-inch drill bit to make holes in the wall at the nest site. Start the first hole where you suspect the nest is located, and drill holes every 6 inches in either direction for up to six feet. This improves your odds of finding the nest location.
Fill a plastic squeeze bottle with boric acid powder. This powder can be found at your local hardware store or grocery store in the cleaning supplies aisle. It is a natural, non-toxic chemical that will kill the ants.
Insert the squeeze bottle into each of the holes and squeeze it to release a puff of boric acid. The ants that come in contact with boric acid will be killed.
Boric acid is safe for use in your home; however, it is dangerous if swallowed, so keep it away from your pets and children.