Bathroom Floor Wet — Where Is the Leak Coming From?
Check the steps below first — if you're not confident, get it fixed safely today.
Post a job — we'll find you an engineer →If you suspect water is getting into a floor void or ceiling below, switch off the electricity supply to that area and call a plumber promptly — water near electrics is dangerous.
A wet bathroom floor where the source is not obvious is one of the most frustrating plumbing problems. Water can travel significant distances from where it originates. Systematic elimination is the best approach — check shower, bath, basin, toilet and supply pipes in order.
Not sure if this matches your problem?
Use our interactive tool — answer a few questions and get a personalised diagnosis.
Most likely cause & what to check
Dry the floor thoroughly, then watch carefully while each fitting is used in turn. Start with the toilet flush, then the basin taps, then the shower. This will usually reveal the source within 5 minutes.
Check the toilet base seal — flush the toilet and watch at the base. A wax ring or pan connector seal failure allows waste water to seep out at the base. You will often smell this before seeing it. The fix is to re-seat the toilet with a new pan connector seal (£8–20).
Check shower tray or enclosure seals — run the shower and watch the tray edges and door seal closely. Perished silicone seals around the tray or door allow water to track under the tray or behind the wall. Re-sealing with sanitary silicone is a DIY repair (£5–15 in materials).
Check below the basin for drips from the trap, waste pipe, or tap tails. Basin overflows are a common hidden leak source — pour water directly into the overflow hole and watch below.
Check the bath panel — remove it and inspect the bath trap, overflow pipe, and any flexible tap hoses. Drips from a bath tap tail, overflow, or trap can pool under the bath for weeks before appearing on the floor.
If the floor is wet under tiles with no obvious source from above, the waterproof tanking under the tiles may have failed (common after 10–15 years). This is a more significant repair requiring retiling.
If the floor below (e.g. kitchen ceiling) is also wet, you have a slow leak that has built up over time. A plumber may use a moisture meter or thermal imaging camera to trace it without breaking down walls.
Not confident doing this yourself?
Post the job and we'll match you with vetted local engineers. Free, no obligation.
🛠 Tools & materials you may need
Was this guide helpful?