How Do Mice Get in Your House?

Mice may be small, but they’re experts at finding ways into warm, sheltered spaces like your home.

They can squeeze through gaps as small as a pencil, making it easy for them to slip inside without being noticed.

Knowing how they get in is the first step to stopping them.

1. Gaps Around Doors and Windows

Even a small gap under a door or around a window frame can be enough for a mouse to squeeze through.

Damaged weather stripping or warped frames are common access points.

2. Holes Around Pipes and Cables

Pipes for plumbing, heating, or air conditioning often leave small gaps in walls.

Mice will exploit these openings to travel between indoors and outdoors — and even between rooms.

3. Cracks in Walls or Brickwork

Over time, brickwork and mortar can deteriorate, leaving tiny holes that mice can enlarge by gnawing.

These are often found around the base of the house or near utility meters.

4. Open Vents and Air Bricks

Vents are essential for airflow, but without proper covers, they provide an easy route inside.

Metal mesh or fine grills can help keep mice out while still allowing ventilation.

5. Gaps in Roofs and Lofts

Missing roof tiles, damaged soffits, or holes in loft eaves can give mice access to your attic space.

From there, they can work their way down into living areas.

6. How to Prevent Mice Getting In

Stopping mice before they enter is far easier than removing them once they’re inside.

Key prevention tips include:

• Seal gaps with steel wool or mouse-proof sealant.

• Install door sweeps on external doors.

• Keep vents covered with fine mesh.

• Repair damaged brickwork promptly.

• Store food in airtight containers to reduce attraction.