These insects often become pests in homes. They usually appear in late fall or early winter and again on warm, sunny days in early spring. They buzz around the home and gather in large numbers at windows, often in rooms that are not regularly used. As we can treat for cluster flies once they have become a pest, the best way to keep them from becoming a pest is to apply a preventative treatment late summer or early fall. If you would like a BC treatment, feel free to get in touch with us!