How to get rid of mice and rats at home

Step 1: Find how they get in

• Mice fit through tiny gaps. IDPH says a mouse can slip through a crack that a pencil will fit into, slightly larger than 1/4 inch (IDPH). Rats can get in through any opening larger than 1/2 inch (IDPH).
• Check where pipes and wires enter, plus gaps around windows, entry doors and garage doors (IDPH).
• Use the right materials. Steel wool mixed with caulking compound makes a good plug. Use metal or concrete for foundation cracks and openings for pipes, vents and utilities. Plastic, wood and rubber can be chewed through (IDPH).
• Renting? Report cracks and holes to your landlord. Local laws may require landlords to address pest problems (University of Illinois Extension).

Step 2: Take away food and shelter

• Store human and pet food in tightly closed containers, and don’t leave pet food out (IDPH).
• Keep garbage in rodent-proof metal or thick plastic containers with tight lids, and fix leaky faucets (IDPH).
• Keep the lawn mowed, and keep wood piles off the ground, at least 12 inches up (IDPH).
• In Chicago, keep your garbage cart lid closed. The city says exposed garbage is the primary reason rodents multiply (City of Chicago).

Step 3: Trap the right way

• Bait: IDPH suggests peanut butter, chocolate candy, dried fruit or a small piece of bacon tied securely to the trigger (IDPH).
• Placement: set traps close to walls, behind objects and in dark corners where you’ve seen signs of mice, so they pass right over the trigger (IDPH).
• Use enough traps. Using too few is a common mistake. Place them no more than 10 feet apart where mice are active (IDPH).
• Live traps work too, but EPA says released rodents may find their way back unless you’ve sealed the entry points (EPA).
• Skip ultrasonic gadgets. IDPH says ultrasonic sound has very limited use in rodent control and there’s little evidence any sound drives established mice or rats out (IDPH).

If you use poison bait

EPA says to protect children, pets and wildlife by using only tamper-resistant bait stations and following all label directions (EPA). Place baits only where children and pets can’t reach them, store pesticides away from food, and remove dead rodents promptly so pets and wildlife don’t eat them (EPA).

Clean up without getting sick

• Wear rubber or plastic gloves when removing dead rodents or cleaning droppings (IDPH).
• Spray the area with diluted household bleach, at least 3 tablespoons per gallon of water, or another disinfectant, and let it soak 5 to 10 minutes (IDPH).
• Bag dead rodents in a plastic bag, then a second bag, and seal it tightly (IDPH).
• Don’t vacuum or sweep before you disinfect (IDPH).

When to call a professional

If a building is heavily infested, IDPH says to consult your local or state health department before you try to control rodents yourself (IDPH). If you hire help, EPA says to choose a pest control company carefully and ask to see its license (EPA). In Illinois, commercial structural pest control businesses are licensed by IDPH (IDPH). EPA also lists the National Pesticide Information Center at 1-800-858-7378 for help finding a professional (EPA).

Rats outside in Chicago? Call 311 or request rodent baiting online. The city’s Bureau of Rodent Control investigates every reported rat sighting (City of Chicago).