A sewage smell in the flat: where it usually comes from

A dried-out floor drain trap is the most common cause

Most Estonian bathrooms and many kitchens have a floor drain (põrandatrapp) with a water seal underneath that blocks sewer gas from rising back up the pipe. If that drain is rarely used — in a guest bathroom, a summer house, or a flat where the shower drain does most of the work — the water in the trap slowly evaporates, and once it is gone there is nothing to stop the smell coming through.

This is especially common after a holiday or in rooms used only occasionally. The fix, if this is indeed the cause, is almost embarrassingly simple: pour half a litre of water down the drain to refill the trap, then check back after a day or two to see whether the smell has gone.

A loose or dried-out toilet seal

The toilet is bolted to the floor with a seal between the base of the pan and the waste pipe, similar in purpose to a wax ring, though most fittings in Estonia use a rubber or plastic seal instead. Over time this seal can dry out, shrink, or shift slightly if the toilet has ever rocked on its base, and once it no longer sits tight, gas escapes at floor level around the pan rather than up through the water in the bowl.

A telltale sign is a smell that gets stronger near the base of the toilet rather than throughout the room, or a toilet that wobbles slightly when you push against it. If the pan moves at all when you press down on the rim, the seal is very likely compromised and needs replacing rather than just re-sealing around the edge with sealant.

The vent stack is not doing its job

Every waste system needs a vent stack (kanalisatsiooni stäkk) running up through the building to let sewer gas escape above roof level and to let air into the pipes so that water traps are not siphoned dry when you flush. In older panel blocks and wooden houses this stack can crack, come loose at a joint, or get blocked by a bird's nest or debris at the roof outlet.

When the vent is not working properly, traps throughout the flat can lose their seal even with normal use, because flushing pulls air — and water — through in the wrong direction. This is harder to diagnose from inside a single flat, since the fault can sit in a shared stack serving several flats, which usually means involving the building's apartment association (korteriühistu) rather than fixing it alone.

What you can check yourself before calling anyone

Before booking a plumber, spend ten minutes working through the drains and fittings in the flat one at a time. Most sewage smells trace back to one specific spot rather than the whole flat, and finding that spot narrows down what needs fixing considerably.

Go room by room and note where the smell is strongest, since that alone often points to the culprit.

• Pour water down every floor drain in the flat, including ones you never use, and see if the smell fades over the next day
• Check whether the toilet rocks or moves when you push on it, and smell around its base specifically
• Run water in every sink and shower for a minute to refill their traps too, in case more than one has dried out
• Open a window and see whether the smell is stronger near a particular wall or fixture rather than even throughout the room
• Ask a neighbour above or below whether they notice the same smell, which points towards a shared vent stack fault

When the smell is a sign of a dangerous situation

A sewage smell on its own is unpleasant but rarely an emergency — sewer gas is unpleasant to breathe in quantity but the low levels from a dry trap are not usually harmful. It becomes more serious if the smell is accompanied by gurgling drains, water backing up, or a smell that is getting noticeably stronger by the hour rather than staying constant.

If you ever smell something closer to rotten eggs that seems to be getting stronger and is accompanied by any hint of gas rather than sewage, leave the flat and contact the gas emergency service rather than a plumber — we do not do gas work and this is not something to investigate yourself.

A genuine sewage backup that brings waste water up through a drain rather than just a smell is also not a wait-and-see situation, since it can mean a blockage further down the shared stack affecting other flats too.

When it is worth calling a plumber

If refilling the traps does not solve it, or the smell is clearly coming from around the toilet base, the next step is worth having looked at properly rather than masking with air freshener. Our plumbing work starts from 45 € per hour, and a straightforward trap or seal check is often resolved within the first hour once we can see the fitting.

If the toilet itself needs the seal replaced, that is toilet repair and fitting work priced from 60 € per job, and it is worth doing properly rather than temporarily, since a loose pan will usually work its way loose again. If the cause turns out to be the shared vent stack, we can tell you what the fault looks like so you can raise it with the apartment association, since work on shared building systems is usually their responsibility to commission.