The short answer
Water coming through the ceiling under a bathroom in a Northern Virginia house is almost always one of four things: the seal under the toilet, the shower or tub (the drain, the grout and caulk, or the valve in the wall), the sink drain, or a water supply pipe. When it drips tells you which. Only after showers points to the shower. Only after flushes points to the toilet. Dripping all the time, even overnight, is a supply pipe, and that one gets shut off now.
Is it worth calling? Yes. By the time a ceiling shows a stain, water has been getting into the floor for a while, and the wood under the toilet or tub soaks it up long before it drips. A wet ceiling is the house’s warning light, like the ones in error codes and warning lights at home.
Right now
- Put a bucket under the drip and move anything you care about out of the way.
- If the ceiling is sagging with water, poke a small hole at the lowest point of the bulge with a screwdriver, bucket under it. The water comes out where you choose instead of bringing the ceiling down.
- If water is near a light fixture or a ceiling fan, turn that circuit off at the panel and leave the switch alone.
- Stop using that bathroom. If it drips with nothing in the bathroom running, close the toilet’s valve, then the main valve for the house (finding your shutoff valves).
- Take photos of the ceiling, the bathroom floor and anything wet before anything gets moved.
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When it drips tells you where
Swipe to see all columns →
Swipe to see all columns →
| When it drips | Most likely | What to look at |
|---|---|---|
| Only after showers | The shower drain, cracked grout, failed caulk, or water splashing past the door | Gaps where the tub meets the tile, water on the floor outside the tub |
| Only after a flush | The wax ring that seals the toilet to the floor, or the bolts between tank and bowl | A toilet that rocks, a stain or soft spot around its base |
| After using the sink | The drain under the sink or the supply lines | A wet cabinet floor, drips at the nuts on the drain |
| All the time, even overnight | A water supply pipe in the floor or a wall | The water meter’s leak indicator, with everything off (how to read it) |
| Only when it rains hard | Probably not the bathroom: a window, siding or roof flashing, with the water following a pipe down | Upstairs windows and the flashing around the vent pipe on the roof |
To pin it down, run one thing at a time and give each ten minutes with someone watching the ceiling. Start with the sink. Then fill the tub a few inches and let it drain. Then run the shower aimed only at the floor of the tub, then at the walls. Then flush the toilet a few times. If the ceiling only drips when the shower hits the walls, it’s grout or caulk, not a pipe. If it drips while the tub drains, it’s the drain.
What you can fix yourself
Caulk and grout. If the caulk where the tub meets the tile is cracked, peeling or dark, cut it out, let the joint dry a full day, and run a new bead of silicone caulk made for tubs. Cracked grout in a shower can be patched with grout from any hardware store. Shower doors leak at the sweep along the bottom, and a new sweep is a cheap part. A sink drain that drips at a nut can often be stopped by snugging the nut a quarter turn by hand. Go easy on old metal drains, which crack.
When it’s the toilet
A toilet sits on a wax ring that seals it to the drain in the floor. When the ring fails, a little water gets out with every flush, straight into the floor and the ceiling under it. The signs: the toilet rocks when you sit on it, the caulk at the base is stained, or the floor around it is soft. The fix is pulling the toilet and setting it on a new seal, and if the flange is broken or the floor under it is rotted, those get fixed first.
A toilet repair runs $250 to $900: wax ring, flange, fill valve or a rebuilt tank. Replacing the toilet runs $800 to $1,300 with the toilet supplied, and there’s $100 off replacing one (current deals). If it’s cracked or rocks on a soft floor, replacing it is usually the better money (what replacing a toilet costs).
When it’s a pipe or the shower valve
A leak that drips with nothing running is a supply pipe, and it won’t stop by itself. A shower valve leaking inside the wall only drips while the shower is on. Both get reached from whichever side costs less to put back, usually a square cut in the ceiling under the bathroom, since a drywall patch costs far less than new tile. Finding the exact spot first runs $200 to $500 (how leak detection works).
Drying it out
Once the leak is fixed, get the ceiling dry. Leave the opening open, pull out any wet insulation, and run a fan or a dehumidifier on it for a few days so nothing stays damp and starts to smell. When it’s bone dry, a drywall patch and paint finish it.
SwiftPro’s plumbers find it, fix it, and show you what failed. If you already know something’s leaking, a plumbing visit is $49 in regular hours, and the price of the fix is in writing before we start. Booking a plumbing repair? The whole-house plumbing inspection is included, so the next drip gets caught too. Our Water Test and Plumbing Safety Check is $29: a licensed plumber walks your plumbing with photos, checks the water heater and tests your water’s hardness at the kitchen table.
Get a plumber on it
Book a plumber online, call (703) 997-9757, or book the $29 plumbing safety check. We answer day or night. Rated 5.0 stars across 1,138 reviews on Google, Angi, Yelp, the BBB and Facebook, Virginia Class A license 2705192276.
Questions people ask
Why is water leaking through my ceiling under the bathroom?
Usually a failed wax ring under the toilet, the shower or tub (drain, grout, caulk or the valve), the sink drain, or a supply pipe. When it drips tells you which: after showers, after flushes, after using the sink, or all the time.
What should I do first if my ceiling is leaking?
Put a bucket under it, turn off any light or fan circuit near the water, and stop using the bathroom over it. If it drips with nothing running, shut the main water valve. If the ceiling sags, poke a small hole at the low point so it drains into the bucket.
Can a toilet leak through the ceiling?
Yes. When the wax ring that seals the toilet to the floor fails, water gets out with every flush and soaks into the floor and the ceiling under it. A toilet that rocks or a stain around its base are the signs.
How much does it cost to fix a toilet leaking through the ceiling?
In Northern Virginia, a toilet repair at SwiftPro, including a new wax ring, runs $250 to $900. The ceiling patch is separate.
