Can rats come up the toilet?

How rats get from the sewer to a house

The brown rat, the common rat in the UK, lives in sewers as well as around buildings, rivers and waste ground. Sewers give it shelter, water and food washed down from kitchens. It is a strong swimmer and climber.

Sheffield City Council lists the usual ways out: broken drains, missing drain covers and outside toilets that have dried out. From a broken pipe under a floor or behind a wall, a rat can get into the boxing around a toilet or under a kitchen sink without going near the bowl. Swimming up through the bend of a toilet that is in use is possible, but it is a far less usual route than a broken pipe.

Signs rats are using your drains

• Rats seen near a manhole cover, gully or outside drain.
• Scratching under the bathroom or kitchen floor, or behind the boxing around pipes.
• Droppings or gnawing under the sink or behind the toilet, with no gap to the outside you can find.
• Rats in the house even after the walls, doors and air bricks have been proofed.
• Slow drains, gurgling or a sewer smell, which can mean a broken pipe.

Mice rarely use drains. If the droppings are small and pointed, look at gaps in walls and around pipes instead.

If a rat appears in the toilet

Close the lid and weigh it down with something heavy. Keep children and pets out of the room and shut the door. Do not try to catch it. Call a pest controller or your council the same day, and do not use the toilet until it has been checked.

Once it has gone, clean the bowl, seat and floor wearing rubber gloves, and wash your hands well afterwards.

Who is responsible for which pipe

On 1 October 2011 the ownership of shared private sewers, and of private drains outside a householder's boundary, transferred to the water and sewerage companies in England and Wales. That leaves most homeowners responsible only for the pipe inside their own boundary that serves their home alone.

Report a broken shared sewer to your sewerage company. A broken drain on your own land is yours to repair.

Rat blockers and drain repairs

A rat blocker is a one-way flap fitted inside a drain. It lets waste flow out but stops rats swimming back in. It is usually fitted in an inspection chamber, after a camera survey of the drain has found the route the rats are using.

A blocker stops rats getting in that way, but the lasting fix is repairing the broken pipe. Redbridge Council also advises replacing broken manhole covers and, after building work, making sure redundant drains are properly sealed so they give rats nowhere to hide.

Keep the drains less inviting: do not pour fat or food scraps down the sink, and do not flush wipes.

Getting help

Drain rats need a professional, because the bait has to go where the rats are, and the route in has to be found. See rat control for what a course of visits involves and what it costs; drain work is usually priced separately. Many councils treat rats, some free, so ask your council first.

If you rent, a broken drain is a repair. Shelter's advice is that a landlord must deal with pests that come in because of a repair they are responsible for. Tell them in writing.