Why gaps keep reopening.
A hole filled with foam, caulk or a wad of steel wool looks fixed for a week. Then a mouse or rat chews through it, and the hole is back. Lasting repairs use materials that teeth cannot beat.
Rodents never quit. A mouse squeezes through a hole as wide as a pencil, and a rat can gnaw a small hole larger. Every night they test edges, so any weak spot eventually fails.
Where entries hide.
The usual spots are less dramatic than most people expect. Many are found only by looking from the attic outward or from the foundation upward.
- Roofline: gaps where roof meets wall, torn soffit screens and loose ridge or gable vents.
- Penetrations: pipes, cables and AC lines that pass through siding or roof.
- Garage: the door corners, bottom seal and gaps beside the frame.
- Foundation: slab cracks, torn skirting, open vents and gaps around crawl doors.
- Vegetation: limbs and fronds that touch the roof.
Materials and where they go.
| Gap. | Material. | Why it works. |
|---|---|---|
| Small crack or pipe gap. | Steel mesh plus hard sealant. | Teeth cannot pull the mesh out. |
| Soffit or vent opening. | Metal screen cut to fit. | Holds its shape against chewing. |
| Roofline joint. | Metal flashing. | Covers a long, narrow gap. |
| Garage door corner. | Heavy-duty seal or metal plate. | Closes the gap rodents squeeze under. |
| Large foundation opening. | Hardware cloth and cement or sealant. | Bars burrowing animals. |
Foam can still serve as a backing, but it never works alone. Anything that stays on the surface for rodents to reach should be metal.
Order of work.
The sequence is simple. Inspect and list the openings. Trap and clear the building. Seal the openings. Then recheck. Reversing the order risks trapping an animal in a wall. The trapping page explains the clearing stage.
Some jobs are staged over several days, with the largest openings sealed first and the smaller ones after the traps stop catching.
Reducing pressure outside.
Sealing works best when fewer animals are pushing on the building. Trim palm fronds and limbs back from the roof. Keep woodpiles away from the walls. Fix dripping spigots. Store pet food and seed in tight tubs. The yard page covers these habits.
Prefer talking to reading? Dial the number and a person picks up at any hour.
Dial (888) 686-4821After the work.
A return visit looks for chew marks at the new repairs, fresh droppings and any new gaps from storms or settling. After heavy weather, walk the building yourself and report new holes. A small repair done early is cheaper than a second infestation.
If damage is found, rodent damage repair handles insulation, ducts and wiring.
Before you call, put the broom down
Thinking about tidying up before a technician comes? Follow the sequence shown, and stop wherever a step feels unclear.
- Leave the broom in the closet. Bristles and vacuum exhaust both fling dry droppings into the air you breathe.
- Fresh air first, cleanup second: thirty minutes with the windows open is the CDC's starting point for closed spaces.
- Protect your hands from start to finish, and finish with a proper soap-and-water wash.
- Wet it thoroughly, wait a few minutes, then lift the mess with paper towels.
- Seal the bag, then drop it in the regular garbage.
- If something feels wrong later, see a doctor and mention the cleanup so they can decide what matters.
Go to the original guidance
If you want the full text, the titles and links are listed below.
- Centers for Disease Control, hantavirus prevention: Where this page's sealing and tidying advice comes from.
- Centers for Disease Control, rodent cleanup guide: Ventilate, soak and bag, in the order the CDC describes.