What should I use to fill mouse holes? - briefly
Use steel wool or copper mesh to block the entry, then apply an exterior‑grade caulk or expanding foam to seal the gap. For long‑term protection, cover the patch with a durable sealant or plaster.
What should I use to fill mouse holes? - in detail
When sealing gaps created by rodents, select a material that resists chewing, conforms to irregular shapes, and adheres securely to the surrounding structure.
Steel wool or copper mesh can be packed tightly into the opening. Their fibrous composition deters gnawing, and they can be covered with a sealant for additional strength. Apply a generous amount of silicone caulk over the packed material to create an airtight barrier.
Expanding polyurethane foam works well for larger voids. Inject the foam until it fills the cavity, then trim excess after it cures. Reinforce the cured foam with a thin layer of acrylic or latex caulk to prevent future penetration.
For permanent repairs in concrete or masonry, use a mortar mix or epoxy filler. Clean the hole of debris, dampen the surface, then press the mortar or epoxy into the gap, smoothing the surface to match the surrounding area.
A practical checklist for filling rodent entry points:
- Identify all openings, including those behind appliances, along baseboards, and in exterior walls.
- Choose a primary filler based on size and material:
- Small gaps (≤¼ in): steel wool or copper mesh + caulk.
- Medium gaps (¼–½ in): expanding foam + caulk.
- Large openings (>½ in): mortar or epoxy.
- Apply the filler, ensuring complete coverage of the void.
- Seal the outer surface with a durable caulk or sealant.
- Inspect the repair after 24 hours for any remaining cracks or signs of chewing.
Regular maintenance, such as trimming vegetation near the foundation and checking for new openings after seasonal changes, enhances the effectiveness of the repairs. Using the appropriate filler and a proper sealing technique eliminates the risk of re‑entry and protects the structure from further damage.