Openings: close it or cover it.
Close the openings that don’t need to be open, and cover the ones that do with removable metal mesh.
First, sort each opening
The mouse-proof standard. Every RV and motorhome can be made mouse-proof. Seal for the smallest invader, the mouse, and you’ve closed the gaps the bigger ones use too. What the standard means →
Many openings on an RV are there for a reason: air for the fridge, furnace or water heater, or access for service. Sealing those shut can cause problems later. So for each one, ask: does it need to stay open?
It doesn’t need to be open: close it
Back the gap with metal, like 1/4-inch hardware cloth or a sheet-metal patch, and seal it in with a sealant made for RVs and outdoor use. Fasten it so it can’t shake loose on the road.
It does need to be open: cover it
Use removable stainless or galvanized mesh, cut to fit and held on with screws or clips, so it comes off for service and goes back on after.
The common mistake: stuffing a gap with steel wool or foam. Mice chew through foam, and steel wool rusts and pulls apart, so the gap opens again. Neither one is a lasting seal.
Where to look first
- Vents and fans
Roof vents, fan housings and the outside vents for the fridge, furnace and water heater need air, so they stay open. Cover them with removable stainless or galvanized mesh. On an appliance vent, use only a screen made for that vent and follow the appliance maker’s guidance. Never block one.
- Storage bay gaps
Shut each storage bay door and look for daylight at the edges and corners. Close gaps in the bay walls and floor with metal and sealant, and replace worn door seals.
- Where wiring and plumbing come in
Look under the sinks, behind access panels, around the water heater, and wherever cables and pipes come through the floor or walls into the living space. CDC notes rodents can get into a vehicle’s passenger compartment through ducting, rusted areas and cable conduit (CDC).
- The underside
Look for torn or loose underbelly covering and damaged floor insulation. Close holes with metal, fastened so it can’t shake loose on the road.
The rest of the RV
Already have mice inside? Catch the ones inside once, and clean up safely →
- Ground connectionsEvery one is a ladderPower cords, water and sewer hoses, tires and stabilizer jacks all touch the ground. Guard each one, or lift it.Read the guide
- Parking and checksBefore it sits, and before you goWhere to park, what to look at, how to tell if something got in, and what to do if it did.Read the guide
Sources
- Centers for Disease Control and Prevention (CDC), How to Clean Up After Rodents (including How to Inspect and Disinfect a Vehicle)
Facts on this page were checked against each source on October 30, 2026.
Find the gaps. Seal them for good. Catch the ones inside once. No poison, ever.