How to Fix a Leaking Sink Faucet in Canton, MA
By Canton 24/7 Plumbing, 2026
Put a dry paper towel under the faucet and a bucket in the cabinet, then run the water. Where the towel gets wet tells you what to replace, and it is rarely the whole faucet. A leaking sink faucet in a Canton, MA kitchen or bathroom is most often a worn cartridge, O-ring, seat or washer that costs little to replace.
This guide sorts leaks by location, walks through a cartridge repair, and covers the under-sink leaks that people mistake for a faucet problem. It also lists the signs that tell you to close the shutoff and hand the job over.
Four places a sink faucet leaks
Dry everything off with a towel, then open and close the faucet while watching each spot in turn.
Out of the spout when off
The cartridge, ceramic disc or washer and seat are not sealing. This is the most common drip.
Around the handle
A worn stem O-ring or a loose packing nut lets water creep up the handle when it is on.
At the base of the faucet
Water pooling around the body points to a failed spout O-ring on a swivel spout or a loose mounting nut underneath.
Under the sink
Supply lines, shutoff valves and compression nuts leak at the connection, not at the faucet itself.
Faucet type decides the repair
Remove the handle and look at what is inside. The parts are different enough that guessing wastes a trip to the store.
| Faucet type | How to recognize it | What wears out |
|---|---|---|
| Compression, two handles | Handles turn several times to seal, separate hot and cold | Rubber washer, brass seat, stem O-ring |
| Cartridge, one or two handles | A cylindrical insert held by a clip or nut | Cartridge body, rubber seals, O-rings |
| Ball, single lever | Rotating ball with a cap and adjusting ring | Rubber seats, springs, ball O-rings |
| Ceramic disc, single lever | A wide cylinder with two ceramic plates | Disc seals, inlet rubber gaskets |
Replace a cartridge in a single-handle faucet
Always close the shutoffs under the sink first and open the faucet to release pressure. Put the stopper in so no screw is lost down the drain.
Take off the handle
Pry off the cap with a small flat screwdriver, remove the set screw with an Allen key or Phillips driver, and lift the handle straight up.
Remove the retaining nut or clip
Some faucets use a dome cap and threaded nut, others use a U-shaped clip. Photograph the arrangement before you pull it apart.
Pull the cartridge
Grip the stem with pliers and pull straight up, rocking slightly. A cartridge puller helps if mineral scale holds it.
Match and install
Take the old cartridge to the store, since small differences in length and notches matter. Grease the new O-rings with plumber's grease and push it home in the same orientation.
Reassemble and test
Tighten the retaining nut, install the handle, then open the shutoffs slowly. Run hot and cold, and check the base and under the sink.
If the leak is under the cabinet instead
Run your fingers along the supply lines and the shutoff valves. A drip that appears on a nut means the compression ferrule is worn or the nut is loose. Snug it a quarter turn at most, because overtightening cracks the ferrule and makes the leak worse.
Braided stainless supply lines are inexpensive and often better than old chrome tubing. Replace both lines together if one has failed, using an adjustable wrench on the valve to keep it from turning.
A shutoff valve that drips from the stem can sometimes be fixed by tightening the packing nut slightly. If the valve will not close fully or the handle breaks off, treat it as a repair for a pro.
Repair the faucet or replace it
A new faucet is often the better choice when the fixture itself is failing, not just its seals.
Repair when
- The body is solid with no cracks
- Replacement cartridges are still sold for it
- The finish is in good condition
- The leak is limited to one seal or O-ring
Replace when
- Parts are discontinued or hard to match
- The body has pitting or hairline cracks
- Several seals have failed together
- Water pressure at the aerator is poor even after cleaning
Low flow or spraying sideways is usually the aerator
Unscrew the aerator at the tip of the spout. Use a rag to protect the finish and turn counterclockwise. Rinse out the screen and check for grit or white flakes. Soak it in vinegar if scale blocks the holes.
Reinstall it with its washer in place. A missing washer leaks at the threads, which people sometimes blame on the faucet body.
When to stop and shut things down
Close the shutoffs and leave the work if a valve will not turn, the faucet body is corroded to the cabinet, or you find a spreading stain on the cabinet floor. Water in a sink base can run along pipes into the floor and the ceiling below.
If a supply line bursts or a valve will not shut off, close the main water shutoff where the line enters the house and call (617) 752-0573. Do not use a faucet repair as an excuse to ignore damp wood, because a slow leak that stays hidden is what causes mold and rot. A plumber using a moisture meter and thermal camera can tell whether the damp is the faucet or something in the wall.
Do not mix electricity and water. If the leak is near a disposal, dishwasher or outlet in the cabinet, switch the breaker off before working.
Canton, MA: cold snaps, grit and permits
Canton has freezing winters and nor'easters. A sink on an exterior wall can freeze when the cabinet has no heat, and a split supply line looks like a faucet leak once it thaws. Open the cabinet doors on very cold nights, and if the leak began after a cold snap, stop and look for a frozen section before you replace parts.
The town's 2023 letter says Canton treats its well water to remove iron and manganese and adjusts pH to reduce lead and copper. If you find grit in the aerator at only one tap, clean that aerator. If several taps show it on the same day, ask the Canton Water/Sewer Division, because the source is outside your fixture.
Under 248 CMR 3.05, repairing a leak in a faucet, valve or other working part of a fixture does not need a permit, but installing a new fixture or moving supply lines can. Ask the Canton Building Department about your specific job.
Sources: Canton Water/Sewer Division 2023 water quality letter via MWRA (town utility report), 248 CMR 3.05 as published by Cornell LII (state regulation), General regional climate note (no figures used)
Canton, MA questions on this topic
My faucet started leaking after a Canton cold snap. Where do I look first?
Check the pipes on the exterior wall under the sink for a split or a bulge, because ice can crack a supply line that only leaks once it thaws. Warm it gently with a hair dryer, never a flame. If you find a split, close the main shutoff and call a plumber.
What if the cabinet floor under the sink is soft?
Soft or swollen wood means the leak has been going on a while. Fix the leak, dry the cabinet with a fan and then check the floor and ceiling below. If you suspect more than one wet spot, leak detection with moisture meters finds hidden water without opening walls.
Do I need a Canton permit to replace the whole faucet instead of repairing it?
The 248 CMR 3.05 exemption covers repairing a leak in a working part. A full fixture swap on existing supply lines is a gray area for homeowners, and new or moved piping is clearly plumbing work. Call the Canton Building Department with the details of your job.
How tight should I make the compression nuts?
Hand tight, then one quarter to one half turn with a wrench. Overtightening crushes the ferrule. If it still weeps, back off, wipe it dry, check the ferrule seat for debris, and retry.
Why does it still drip after I changed the cartridge?
The usual causes are a cartridge turned the wrong way, a scratched or pitted brass seat, or a bit of debris under a rubber seal. Pull it, rinse the valve cavity, check the seat for scoring, and reinstall it with the handle in its off position.
Related services and nearby towns
Stoughton's 2023 water report advises flushing a tap for 30 seconds to two minutes after water has sat for hours, a good habit before you test a repaired faucet in Stoughton. Randolph's water was reported as soft at 39.6 ppm in 2024, so neighbors in Randolph see scale less often. For a failed valve or a faucet that cannot be rebuilt, see our faucet repair service.
Sources and standards
These are the primary sources this page relies on. Anything not listed here is general plumbing practice, and local rules should be confirmed with the town.
- 248 CMR 3.05, the Massachusetts plumbing and gas fitting regulation, as published by Cornell LII
- Town of Canton Building Department, online permitting page (plumbing and gas permits)
- Canton Water/Sewer Division 2023 water quality letter, distributed through the MWRA community page
Plumbing problem in Canton right now?
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