A leaking toilet usually means one of two things: water keeps running from the cistern into the bowl, or water appears on the floor. The first wastes water all the time; the second can soak into the floor and cause water damage. This guide explains how to tell them apart, what you can safely fix yourself, and when replacing the toilet makes more sense than repairing it.
Most toilets in Finnish homes are either floor-standing, with the cistern on the back of the bowl, or wall-hung, with the cistern hidden in the wall. In both, a fill valve (täyttöventtiili) with a float refills the cistern, and a flush valve (huuhteluventtiili) releases the water into the bowl when you press the dual-flush button.
First, close the toilet's own valve
If there is water on the floor, stop the supply before you start investigating. Behind or beside the toilet there is usually a small angle valve (kulmaventtiili) with a hose running up to the cistern. Turn it clockwise until it stops; some older valves need a flat screwdriver.
If the valve doesn't hold or is leaking itself, close the apartment shut-off valve if your home has one, or contact the maintenance company (huoltoyhtiö). Then dry the floor and the outside of the cistern so you can see where fresh water appears.
Running into the bowl or onto the floor?
Before you fix anything, work out which problem you have:
- Water keeps running into the bowl. You hear a faint trickle or hiss, a thin stream runs down the back of the bowl, or the cistern refills now and then although nobody has flushed. A limescale or rust streak may form where the water runs. The fault is inside the cistern.
- Water on the floor. Something is leaking at a connection, a hose, a seal or the porcelain. This is more urgent, because water can get into the floor structure.
Also note when the water appears. The hose, the angle valve and the fill valve connection are under constant water pressure, so they drip all the time. The seal between the cistern and the bowl and the drain connection usually leak only when you flush.
A toilet that keeps running
A running toilet won't flood your bathroom, but it uses water day and night, which shows on the bill if your flat has its own water meter. Lift the cistern lid, or on a wall-hung toilet remove the flush plate, and look at the water level.
Water flowing into the overflow: the fill valve
In the middle of the cistern is the flush valve, with an overflow tube that sends excess water into the bowl. If water is running over the top of the tube, the fill valve isn't shutting off in time. The float may be set too high or stuck, or the valve may be clogged with limescale or have a worn seal.
The water level should settle clearly below the top of the overflow tube, and many cisterns have a mark for the correct level. The float is usually adjusted with a screw or a sliding clip. Lower it a little, flush, and see where the level stops. If that doesn't help, the fill valve needs replacing.
Level below the overflow, but water still trickling: the flush valve
If the level stays below the overflow and water still runs into the bowl, the seal at the bottom of the flush valve is usually leaking. Limescale and dirt build up on it, or the rubber hardens. A sticking flush button can also hold the valve slightly open.
Confirm it with a dye test: add a few drops of food colouring to the cistern, don't flush, and check the bowl after half an hour. If the colour has reached the bowl, water is getting past the flush valve. Often it is enough to clean the seal and the surface it sits on. On many cisterns the flush valve comes out with a twist or a lift once you have closed the angle valve and flushed the cistern empty. A worn or cracked seal should be replaced.
Water on the floor: where it usually comes from
Dry everything and put a piece of kitchen paper under each joint. The paper that gets wet first shows where the water comes from. The usual suspects are:
- The connection hose. Hoses age, braided ones can rust or kink, and the nuts can work loose. A cracked or rusty hose should always be replaced.
- The angle valve. An old valve often starts dripping from the spindle when it is turned after years of not being touched. Gently tightening the small nut around the spindle may stop it, but often the valve has to be replaced, which means shutting off the water to the whole apartment or the riser.
- The fill valve connection. The joint under the cistern can seep if the nut has loosened or the washer is worn.
- The seal between the cistern and the bowl. On a floor-standing toilet the cistern is bolted to the bowl over a seal. A leak here shows at the back of the toilet, usually after flushing.
- The drain connection. If the rubber connector (liitäntämansetti) between the toilet and the drain is worn or the toilet rocks, water comes out when you flush, and you may notice a sewer smell. With a floor outlet, the water can run into the floor structure without showing.
- Cracked porcelain. A hairline crack can't be reliably repaired, so a cracked toilet or cistern needs to be replaced.
Condensation: a sweating cistern isn't leaking
In summer, moisture from warm, humid air condenses on the outside of the cold cistern, and the drops run down to the floor like a leak. With condensation (kondenssi) the whole cistern is evenly damp, whereas a leak starts from one spot. Ventilate the bathroom and make sure the toilet isn't running, as cold water constantly flowing into the cistern makes the sweating worse.
What you can safely fix yourself
These running-toilet fixes are usually fine to do yourself:
- adjusting the float and the water level
- cleaning or replacing the flush valve seal
- checking a sticking flush button
- carefully tightening a loose hose nut (plastic threads crack easily if overtightened)
Leave the rest to a professional: replacing an angle valve, repairing the cistern-to-bowl seal or the drain connection, and anything beyond simple adjustments on a concealed in-wall cistern. These jobs mean removing the toilet or the cistern, or shutting off more of the water supply. It is also worth checking the safety requirements (suojeluohjeet) in your home insurance policy, which may set conditions on how water fittings are installed. We replace fill valves, hoses and angle valves as small plumbing jobs.
When to replace the whole toilet
A small repair usually costs less than a new toilet, but replacement makes more sense when:
- the porcelain is cracked
- the toilet is old and spare parts are no longer available
- there are several faults or leaks at once
- the drain connection of an old toilet leaks: the toilet has to come off anyway, so fitting a new one at the same time is often the sensible choice
Replacing a standard floor-standing toilet costs a fixed €235.31, and you buy the toilet yourself. Our article on toilet replacement cost explains what the price includes and how to choose a toilet that fits your drain.
In an apartment building: report floor leaks
If water has reached the floor, tell the maintenance company or the property manager (isännöitsijä), even if the leak has already stopped. Water can soak into the structure and down to the flat below without showing on your side. If you rent, tell your landlord as well.
Responsibility for toilet repairs varies between housing companies (taloyhtiö), so check the maintenance responsibility table (vastuunjakotaulukko) or ask the property manager before ordering a repair. Replacing a part inside the cistern usually needs no notice, but many housing companies require a written renovation notice before the toilet itself is replaced.
Summary
- A running toilet is usually caused by the fill valve, the float or the flush valve seal, and is often easy to fix.
- Water on the floor is more urgent: close the angle valve, find the leak and, in an apartment building, tell the maintenance company.
- A cracked or very old toilet is usually worth replacing rather than repairing.
See our toilet installation and replacement page, or contact us and send a photo of the leak to arrange a repair or a replacement.