Rats are typically seen or heard in the attic, garage, basement, or wall voids. Signs of a rat infestation include droppings, tracks, and loosely constructed nests made of rags, paper, and other scraps. Pipes, beams, and wiring may be gnawed. Books, fabrics, furniture, and other objects may be chewed or shredded, and packages of food may be gnawed open and the contents eaten.
Place traps or baits in areas that you see rat activity. Seal all openings larger than 1/4 inch leading into your home. Remove any food sources that could attract rats by covering your trash, storing pet food in sealed containers, and elevating any compost piles. Eliminate sources of water that rats would have access to as well.