Fill a clean, plastic condiment container 1/3 full with a dust insecticide recommended for the type of bug you have.An old ketchup container with a tip works well. Dust insecticides such as deltamethrin, pyrethin, carbaryl and cyfluthrin are useful in killing carpenter ants, bees, wasps and many other bugs inside your home.
Insert the tip of the bottle into the hole created by the bug. If the hole is not big enough, enlarge it with an electric drill and drill bit.
Squeeze the plastic container briskly to squirt the insecticide into the hole in the wall. Do this five or six times to ensure that it spreads throughout the wall void. Repeat this in all the holes in the wall.
Squirt the dust insecticide into any cracks or crevices in the wall as well. Do this in rooms where you have spotted bugs.
Wipe up any insecticide dust on the wall or floor near the hole with a damp paper towel. This prevents pets or small children from ingesting the product.
Discard the empty container to keep anyone from using it for food.