During the first winter in our home (New construction) we caught 5 mice in 3 days! We immediately had a pest control company come out to assess the situation. They found 8-9 holes that had not been closed during construction. Small holes behind the washer/dryer, stove, under the sinks, anywhere tubes were coming out of the walls. They said that until the holes were closed we would continue to have problems. The construction company closed the holes and we haven’t had problems since then (Four years ago). The rats/mice need an entry point once the entry point is closed the problem is solved.