Rats in drains: how they get in and how to stop them

Rats are strong swimmers and good climbers, and they move easily through sewer pipes. In a sound drain, they have nowhere to go except back the way they came. Defects give them an exit.

Scratching or scurrying in walls, ceilings or under floors, especially at night, is often the first clue. Outside, look for droppings or burrows near inspection chambers, gnaw marks on pipes or skirting, and holes appearing in the ground along the line of the drain. An unpleasant smell from a wall or floor void can come from a damaged pipe or from a rat that has died there.

If rats keep returning to the same area despite treatment, or appear in a part of the house with no obvious way in, a drain is a likely route.

Pest control deals with the rats that are already inside. But if the drain is still damaged, more will follow from the sewer. That is why some properties see the same problem month after month. The lasting answer is to find the defect and close it.

We work on the drain, not the rats. We do not lay poison or traps; that is for a pest control specialist, and the two jobs work best side by side.

It is worth remembering that a drain defect can let rats into one property and its neighbours at the same time. If people nearby are seeing the same signs, a shared pipe may be the route, which is another reason a camera survey is worth having before any work is planned.

A CCTV drain survey is the most reliable way to find where rats are getting out. The camera shows cracks, open joints and abandoned connections, along with signs such as nesting material or soil washed into the pipe. Its position is measured so the repair can be targeted.

The repair depends on what the camera finds. A single crack or open joint can often be sealed with a patch from inside. Where damage runs along the pipe, relining seals the whole length. A broken or collapsed section is dug out and replaced. Disused connections are capped off, and missing or damaged chamber covers are replaced so they sit securely. Our drain repairs page covers these options, and the drain repair costs guide explains what affects each.

Check that chamber covers outside are intact and sitting flat. Keep food waste, bird feed and bins secure so rats are not drawn to the garden. Avoid blocking holes you find without knowing where they lead, as rats may simply dig another. If you are working with a pest controller, tell them you suspect the drains; they may suggest a survey.

Safety note: wear gloves when dealing with droppings or nesting material, and do not lift chamber covers with bare hands.

If you think rats are using your drains, get in touch and tell us where you have seen signs. A smell alongside the problem? Our guide to why drains smell may also help.