Proofing comes after treatment
Sealing every gap while rats are still inside can trap them in walls and floors, where they chew new holes or die out of reach. The order is: deal with the rats, confirm activity has stopped, then close the routes.
The rat-proofing checklist
- Gaps around pipes and cables through outside walls — sealed with materials rats cannot chew through (see proofing pipe gaps)
- Air bricks — broken grilles replaced, never blocked, as floors need ventilation (see air bricks)
- Back doors and garage doors — thresholds repaired and gaps under doors closed
- Joints where extensions meet the house — cracks filled
- Old redundant pipe holes — properly filled, not just covered
- Overhanging branches and climbing plants near the roof — cut back
Why expanding foam alone is not enough
Rats gnaw through soft materials such as expanding foam, silicone and plastic with ease. Gaps need filling with something they cannot chew — cement-based fillers, metal mesh or purpose-made plates — with foam used only as part of that.
Drains and rat blockers
If rats have been coming from the drains, sealing gaps above ground will not stop them. A drainage contractor can survey the drain with a camera, repair the defect and, where appropriate, fit a one-way rat blocker that lets water out but stops rats coming back up. See how rats get into Brent homes for how to tell when the drains are to blame.
What our rodent proofing service covers
Our rodent proofing service is £180 for up to one hour of work on small, accessible holes and gaps — typically around pipes, at air bricks, under doors and behind kitchen units. Larger or structural work is one for a builder, and drain work for a drainage specialist. You can book rodent proofing here.
Proofing the loft and roof
Rats that reached the loft may have climbed inside the walls or come over the roof. Check the eaves for gaps and cut back branches — the approach is covered in rats in the loft.
If rats are still getting in
If you have proofed and rats are still appearing, the route may be one you have not found. Our guide on why rats keep coming back covers the usual suspects, and you can book rat control — £190 for a flat, £240 for a house.
