Rodents vs RVs: sealing gaps and snap traps have the evidence, peppermint and dryer sheets don't

The scorecard

Why an RV is easy to get into

An RV is a box full of holes. Plumbing and wiring pass through the floor, slide-outs have seals that compress unevenly, and the basement bays, furnace and water heater vents, and generator compartment all open to the outside. CDC's figure is a quarter inch, about the width of a pencil. A stored rig also offers what mice look for: shelter, nesting material in cushions and insulation, and no movement for months. CDC notes that rodents are more likely to nest in vehicles that are used infrequently.

What works, in order

1. Seal the gaps

Exclusion is the only method in our list that keeps mice out instead of dealing with them once they're in. Crawl under the rig with a flashlight and look up for daylight around pipes, cables and the frame. CDC's method is steel wool in small holes, held in place with caulk or spray foam, and metal, hardware cloth or sheeting for larger openings. UC IPM says plastic screening, rubber, vinyl, expanding foam and wood are ineffective on their own because mice gnaw through them, and that steel wool may rust over time.

2. Trap what gets in

Snap traps tell you whether mice are getting in and remove the ones that do. Set them along walls, in cabinets and in the basement bays, close together, since house mice seldom travel more than 30 feet from the nest. CDC advises against glue and live traps. Check them on every visit.

3. Bait stations, with caution

Rodenticide stations kill mice, but UC IPM notes the mice often die inside the structure, and in an RV that can mean a dead mouse inside a wall or duct. CDC reserves poison for infestations that persist. If you use them, keep stations outside the living space, follow the label, and remember pets and wildlife.

4. Pick the right spot

Tall grass and brush give mice cover right up to the tires. CDC's household advice is to keep vegetation trimmed and brush cleared. A paved or gravel lot with mowed edges, or an indoor RV storage building, removes much of that cover. No study we found compared rodent problems by lot surface, so treat this as sensible habitat advice rather than a tested result.

Step-by-step storage checklist

1. Empty every food item, including sealed packages, pet food, spices and toiletries with food scents. Prop the fridge open after cleaning it.
2. Clean crumbs from the floor, under the dinette and inside drawers.
3. Inspect from below with a flashlight for gaps around pipes, cables, the furnace and water heater, and the slide-out seals.
4. Seal gaps of 1/4 inch or more with steel wool or metal mesh and caulk or foam; use hardware cloth or metal for larger openings.
5. Cover exterior vents that can be closed while stored, following the appliance manual, and remove covers before use.
6. Set snap traps inside cabinets, in the basement bays and in the engine compartment if motorized.
7. Remove nesting material such as paper towels, rags and loose bedding, or store them in sealed bins.
8. Park on pavement or gravel away from tall grass, brush and woodpiles where you can; compare outdoor RV storage and covered RV storage lots by surface.
9. Skip mothballs, dryer sheets and ultrasonic boxes. The first is harmful and the others lack evidence.
10. Check every few weeks, reset traps, and look for droppings and gnawed wire insulation.

If you find droppings: CDC hantavirus cleanup steps

CDC says that when fresh urine, droppings or nesting material from an infected rodent are stirred up, hantavirus can get into the air, and people are infected by breathing it. Its cleanup steps are built to avoid that. For vehicles, CDC says to air the vehicle out by opening the hood, doors and trunk for 20 minutes before inspecting. For cabins, sheds and other closed spaces, it says to open doors and windows for 30 minutes and leave during that time.

1. Ventilate first, 20 minutes for a vehicle or 30 minutes for a closed building, and stay out while it airs.
2. Wear rubber or plastic gloves, plus a long-sleeved shirt for a vehicle.
3. Do not sweep or vacuum urine, droppings or nests. CDC says this can put virus particles in the air.
4. Spray until very wet with an EPA-registered disinfectant or a fresh bleach solution of 1.5 cups of bleach per gallon of water (1 part bleach to 9 parts water), and let it soak 5 minutes or as the label says.
5. Wipe up with paper towels, then double-bag droppings, nests and dead mice and put them in a covered trash can.
6. Disconnect the battery before inspecting a motorhome's engine compartment, and reconnect it when the area is dry.
7. Replace the air filter if nesting material is in the air intake.
8. Wash gloved hands, then bare hands, with soap and warm water. For heavy infestations CDC recommends coveralls, goggles and a respirator with a HEPA filter.