House flies breed and multiply anywhere they have access to waste products. General locations are garbage disposals and trash receptacles, but they also breed in potted plants and vases of fresh-water flowers. These environments provide the moisture that fly larvae need to thrive.
Improving sanitation and removing breeding sites help to eliminate the presence of house flies. Prevent flies from entering the house by keeping doors closed and replacing damaged screens on windows. Discourage flies from infesting by keeping indoor trash cans closed, keeping trash bags tied, placing outdoor trash receptacles as far from doors as possible, and cleaning trash receptacles frequently. In addition, pesticides are often used for persistent pest control issues.