Rodents guide
How Mice Enter Homes: Small Gaps That Matter
Find common mouse entry routes around garages, doors, pipes, cabinets, vents, and foundations.
Last updated September 20, 2026.
Start low
Mice often use gaps beneath doors, at garage corners, around pipes, behind cabinets, and where siding or stucco meets another material.
Follow interior evidence
Droppings and gnawing near wall edges can help trace a route back to a utility penetration or void. Sealing random gaps is less useful than following fresh signs back to the route.
Use durable repairs
Foam alone is easily gnawed and may hide an unfinished gap. Materials should fit the surface, allow required ventilation, and be checked after control work.
A small gap can connect several rooms
An opening around a garage corner or utility pipe may lead into a wall void that reaches a kitchen or laundry room. That’s why the place where droppings appear isn’t always the entry point. Following wall edges and plumbing routes can reveal the connection.
Repair materials should match the opening
A door sweep, vent repair, masonry patch, or fitted metal barrier may each be appropriate in different places. Foam by itself is easy to damage and can conceal an unfinished repair. Exclusion should remain inspectable and preserve required drainage and ventilation.
A useful order for checking a home
Begin where fresh evidence appears, follow wall edges toward utilities or doors, then inspect the matching exterior. This inside-to-outside sequence is more efficient than sealing every visible crack and makes it easier to verify whether the repair actually changed the activity.
What to do next
Record what you see before cleaning or applying a product. If the evidence keeps returning, could involve damage, or is difficult to identify, compare it with the mice identification guide. The related mouse control page explains inspection and service considerations.