Can Mice Climb Walls? (Yes — Here's How They Get In)

Yes — mice are superb climbers. They can run up rough vertical surfaces like brick, render and timber, climb cables, pipes and wires, and even scale the inside of cavity walls. Combined with their ability to squeeze through a gap of just 6mm — about the width of a pen — that's how they end up in lofts, upstairs rooms and kitchen units.

Just how good are they?

• Climbing: they grip rough surfaces easily and climb brick walls, fences and cables.
• Squeezing: an adult mouse fits through about 6mm — if a biro fits, a mouse can too.
• Jumping: roughly 25cm vertically from a standing start.
• Balance: they run along wires, pipes and the tops of walls.

How mice get into a house

• Gaps around pipes, cables and vents.
• Under doors and around poorly sealed frames.
• Air bricks and vents without fine mesh.
• Gaps at the roofline and along pipework into lofts.
• Cracks in brickwork and around windows.

How to stop them

Proofing is about sealing gaps, high and low. Fill holes with wire wool and sealant or metal mesh (mice gnaw through foam and plastic), fit bristle strips to doors, mesh over air bricks, and seal where pipes and cables enter. Keep food sealed and clear crumbs.

When to call a professional

If you hear scratching in walls or the loft, find droppings in more than one room, or still catch mice after blocking the obvious gaps, get a professional in — they'll find the entry points you've missed and proof the property properly.