A Rat Came Up the Toilet

Right now

Close the Lid and Weight It

If there is one in the pan as you read this:

• Shut the lid and put something heavy on it. A toolbox, a full washing-up bowl, a couple of paving slabs if they are to hand. Do not stand on it.
• Shut the bathroom door and put a towel along the bottom.
• Do not flush repeatedly. It rarely sends them back and it may drown the animal in the pan, which leaves you with a worse job.
• Do not reach in with anything, and do not try to grab it. A cornered rat bites, and a rat bite needs medical attention.
• Do not pour bleach or anything else in. It does not work and it makes the next step unpleasant for whoever deals with it.

Then ring somebody. With the lid weighted and the door shut, the situation is contained and there is no rush beyond your own comfort.

Why it happens

They Swim, and the Trap Is Not a Barrier

Rats are strong swimmers and can hold their breath for a surprising time — long enough, comfortably, to get through the water seal in a toilet trap, which is only a few inches of standing water in a short bend.

The route is: sewer, into your drainage through a defect or an open connection, up the soil stack or along a branch, and through the pan trap. The toilet is simply the last bit, and it is not doing anything wrong — a trap is designed to block air, not animals.

Ground-floor toilets are the ones this happens to, because the climb is short. A downstairs cloakroom that is rarely used is the classic: the trap may even have partly evaporated, which makes it easier still.

It is worth saying how rare it is. Most drain rat problems never produce a rat in a toilet; they produce noise under the floor.

Afterwards

It Is a Symptom, Not the Problem

A rat in the pan means the drainage is open somewhere between the sewer and your building. The toilet is where it surfaced, not where it got in.

So the useful response is not "how do I stop them coming up the toilet" — it is finding and closing the route. A blocker at the last chamber deals with it at source. Toilet-pan devices exist, and they treat one fixture while leaving the rest of the system open, so they are a poor substitute.

The other thing to do is establish how long the route has been open, because a rat that reaches a toilet has been in the private system for a while and there is usually activity under the floor as well. Look for droppings near pipe entries and listen at night.

Little-used downstairs toilets are worth flushing weekly. A trap that has evaporated is both a smell and an open door.

Short answers

Drain Blocker Questions

Going further

Drain and Rat Guides