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Pest Control

Seal Entry Points Against Mice and Rodents

MODERATE45 minPest ControlPart of Fall Maintenance

Why It Matters

Mice can squeeze through a hole the size of a dime. Sealing entry points before fall prevents winter infestations.

Quick Guide

  1. 1

    Gather your tools and materials

    You'll need: Caulk gun, Flashlight. Materials required: Steel wool, Expanding foam, Exterior caulk.

  2. 2

    Perform the seal entry points against mice and rodents

    Walk around your home's exterior and seal any gaps, cracks, or holes larger than 1/4 inch with steel wool and caulk. Safety note: Wear gloves when handling steel wool.

  3. 3

    Verify and clean up

    Check that the work was completed correctly and clean up your workspace. If extensive gaps around utilities or foundation, consider calling a professional.

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Tools & Materials

Tools

  • Caulk gun
  • Flashlight

Materials

  • Steel wool
  • Expanding foam
  • Exterior caulk

Community Tips

TipKasa Team

Steel wool remains the most effective first barrier because rodents cannot chew through it, unlike foam or caulk alone—pack it firmly into holes, then seal over it with expanding foam like Great Stuff Pro ($12-16) for a permanent, tamper-proof seal that hardens in 24 hours.

WarningKasa Team

Expanding foam alone creates a false sense of security since mice can chew through it within weeks; always use steel wool as the core barrier, as rodents instinctively avoid the sharp texture and will seek easier entry points elsewhere.

Cost InfoKasa Team

Sealing a typical home's foundation and wall penetrations costs $40-80 in materials (steel wool, expanding foam, and exterior caulk like Sikaflex 11FC at $8-12 per tube), versus $300-800 for professional pest control visits or $1,500+ for structural damage repair from established infestations. ---