Signs Your Shower Is Leaking Into the Ceiling or the Unit Below

Published 12 November 2026

Why shower leaks are easy to miss

A leaking shower rarely starts as a puddle on the floor. Water slips through a failed silicone joint, a cracked grout line or a gap at the floor-to-wall junction, then travels through the wall cavity or the floor slab. In a house, that often shows up later as a stain on the ceiling of the room below, or as swollen skirting in the hallway. In a unit, it can appear in the apartment underneath, sometimes weeks after the leak began.

That delay is why people in Wollongong, Figtree and along the northern beaches often live with a leak longer than they realise. The shower itself can look almost normal. By the time paint bubbles or a neighbour complains, moisture has already been sitting in the substrate.

Signs inside the shower

Start with the joints, because that is where most showers fail. Run a finger along the silicone at the floor-to-wall junction, around the hob or step, and at the corners. If it has peeled, cracked, gone black and soft, or pulled away from the tile, water can get behind it every time you shower.

Other signs to check:

• •Grout that is dark, soft, crumbling or missing in spots, especially on the floor and at the wall-to-floor junction
• •A hollow or drummy sound when you tap a floor tile, which can mean water has been sitting underneath
• •Loose or rocking tiles, or tiles that have lifted at a corner
• •A persistent musty smell that comes back after you clean
• •Mould that returns in the same corners despite regular wiping
• •Silicone that was clearly added over the top of an older, failed bead

None of these signs proves, on its own, that water is escaping the shower. They do tell you the seals are no longer doing their job, and that a proper check is worthwhile before a small leak becomes ceiling or floor damage.

Signs outside the shower, including the room or unit below

Look just outside the enclosure as well. Skirting boards that have swollen, paint that is bubbling, or a floor that feels soft next to the shower hob are all worth taking seriously. In a two-storey house, inspect the ceiling directly below the bathroom: brown rings, flaking paint or a cold, damp patch after someone has showered are classic signs.

In a strata unit the first warning is often a complaint from the neighbour below, or a damp patch their painter has noticed. If that happens, do not assume it is “just condensation”. A leak from a shower above is a common cause, and the sooner it is found, the less damage there is to make good. Our strata and real estate shower repair page explains how we work with committees and agents on this kind of job.

A musty cupboard beside the bathroom, rusty screw heads on a nearby vanity, or mould on the back of a shower wall that faces a bedroom can also point to water travelling through the wall. If you are unsure, it is better to have the moisture read properly than to keep watching it.

What those signs usually mean — and what they do not

Failed grout and silicone at the perimeter are the usual path for water to leave a shower. That is a sealing problem, and it is the kind of work we do every day: diagnosing the leak, then resealing and, where needed, regrouting without a strip-out.

A leak can also come from a pipe or the waste. That is a different job. It is why a plumbing pressure test is part of our diagnosis. If the test shows a pipe problem, we show you the result so a plumber can deal with the pipe. We do not guess, and we do not start sealing over a plumbing fault.

Condensation can also leave moisture on a cold ceiling, especially in winter with poor ventilation. A moisture meter and thermal camera help tell the difference between surface condensation and a leak that is wetting the structure. That is the point of a proper diagnosis, not a quick look from the doorway.

How we diagnose a leak without removing tiles

Our shower leak detection is non-destructive. We use thermal imaging to see temperature differences that moisture leaves on and behind the surface, a moisture meter to confirm readings, and a plumbing pressure test to check the water supply. We do not need to pull tiles off to find where the water is going.

That diagnosis is included in both of our fixed-price packages: $599 for a standard single shower and $799 for a double or walk-in, all-inclusive, with no travel surcharge across the Illawarra. Most repairs take 3–4 hours, and the shower can usually be used again after 24 hours.

If you already have a damp ceiling or a complaint from the unit below, take a few photos and give us a call. The earlier we can see the path of the leak, the easier it is to stop it and to document what we found for a strata committee or an insurer if you need that.

What to do in the meantime

Until the shower is checked, shorter showers and a bath mat that keeps water on the tray rather than over the hob can reduce how much water escapes. Wipe the joints dry after use so you can see whether they are still failing. If water is dripping into a room below, catch it in a bucket and keep the area ventilated. Do not rely on another layer of silicone over damp, failed sealant — that usually fails again and can hide the real joint.

If you live in a unit, tell the strata committee or managing agent in writing and attach photos. Our guide on who is responsible for a leaking shower in a NSW strata unit covers the usual starting points, and you should still take advice on your own scheme.

Then book a diagnosis. A leaking shower does not improve on its own, and the cost of repairing someone else’s ceiling is almost always higher than dealing with the seals promptly.