Most shower and bathtub leaks start at a connection: the valve, the drain, a corner, a grout line, the pan, or a window sill in the wet wall. The stain on the ceiling below, the musty smell, or the soft paint next to the tub is often late. Water was already in the wall. Bath Pro SD refers licensed independent remodelers and plumbers. This brand does not open walls and does not diagnose a leak from a photo.
This page is the leak-source map. Drain and sewer surprises covers hidden drain lines that show up mid-remodel. Why shower tile cracks covers a cracked field of tile. Do not mix those jobs.
Signs that are worth taking seriously
Water stains or dark patches on the ceiling under the bath. Bubbling or soft paint beside the tub. A musty smell that returns after cleaning. A puddle at the base after the shower. Tile that looks swollen or sounds hollow. One sign can be a cartridge drip. Several signs together usually mean water is leaving the wet area.
A tub that loses water with the stopper down can be a drain gasket, not a pan. A shower that stains only after a long hot shower can be a valve or a grout path. None of those guesses replace a licensed look.
Where the water is actually leaving
Valve. The mixing valve sits in the wall. A worn cartridge often drips at the head or spout and stays a plumbing parts job. A valve that was never blocked, and that wiggles when you turn it, can stress the connections behind the trim. That leak is hidden. The escutcheon can look dry while the cavity is wet.
Drain. Bathtub drains are often set with plumber’s putty or a gasket that dries out. Overtightening can crush the gasket. The leak sits under the tub. You will not see it until someone pulls the tub or cuts an access panel.
Grout and missing silicone. Cracked grout and a failed tub-to-tile bead let water into the wall. Recaulking a sound wall is maintenance. Recaulking a wall that is already wet is a delay.
Pan. A failed liner, a flat mud bed, or a prefabricated pan that was never sloped will wet the ceiling below. A flood test is the check during a rebuild. Bath Pro SD does not publish a flood-test duration. Ask the installer which test the system manufacturer and the inspector want.
Window in the shower. Many San Diego coastal cottages, including older Del Mar, Solana Beach, and Pacific Beach baths, have a window in the wet wall. That opening needs a sill that drains, flashing, and a detail that keeps water off the framing. A remodel that ignores the window is a leak waiting. See shower windows in San Diego bathrooms.
One-piece surrounds. Cracked fiberglass and a failed gel coat can weep at corners and at the drain. That is a replacement conversation, not a recaulk.
Older San Diego houses still have cast-iron drains that rust and scale. New showers leak too when the membrane, the valve blocking, or the pan was rushed. Age is not the diagnosis.
What you can check without opening the wall
Look at corners, the tub-to-tile joint, and grout after a shower. Press gently on the drywall beside the wet wall. Watch the ceiling below on the next use. A moisture meter on the surrounding drywall can show a pattern. It cannot name the failed part.
Do not keep using a shower that is staining the room below. Cut the water to that bath if you can, and call a licensed plumber or bathroom remodeler.
When the wall has to come open
Surface drips at a shower arm or a cartridge can be a parts swap. Water in the cavity, high meter readings, or a smell that will not leave means someone has to see the framing. You will not know the spread until the wall is open. That is when a shower remodel or a bathtub replacement replaces a failed assembly.
For permits, start with City of San Diego Development Services if the address is in the city, or County Planning & Development Services if it is unincorporated. Other cities have their own departments. Describe the plumbing and the wall, not only the word leak.
Frequently asked questions
Can cracked grout cause a real leak?
Yes. Grout is not waterproofing. A cracked joint or a missing silicone bead at a change of plane can wet the board behind the tile. If the wall is still dry, recaulk or regrout. If the wall is soft or stained, inspect the wet wall.
Why do valves and drains leak so often?
They are holes in a system that is supposed to hold water. A loose valve, a dried gasket, or a pan that was never flooded will show up later, often on the ceiling below. Ask the remodeler how the valve is blocked and how the drain is tested.
Should I call a plumber or a bathroom remodeler?
A dripping cartridge or a loose shower arm is often a plumber. A failed pan, a wet wall, or a surround that has to come out is remodeler work, with a plumber on the same job. Ask who is on the CSLB record for each trade.
Does Bath Pro SD fix leaks?
No. Bath Pro SD is a referral service. Call (858) 400-4896, describe the stain, the smell, and which floor is under the bath, and we match you with a licensed independent pro.