Low water pressure at one faucet

A single weak faucet is usually a small, local clog — most often just mineral gunk in the little screen at the tip — not a problem with your whole plumbing system. This one is often free to fix in a few minutes.

tuneWhat are you noticing?

Select anything that matches and the checklist below reorders to fit. Not sure? Skip it.

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In Canada, when one faucet runs weak the clogged aerator is the first thing to rule out — and the easiest. Unscrew the screen at the tip of the spout by hand (or wrap it in a cloth and use pliers), and look inside: white scale, sand, or grit means you've likely found it. Rinse the parts, or drop in a cheap replacement, and flow usually jumps right back. Costs nothing to check.

Ranked from real-world failure data. The order updates as you select what you’re noticing above.

Likely causes, in the order to check them

Showing the typical order

Beginner-friendly Doable, with care Safety-critical Call a pro

visibilityHow to check

Unscrew the aerator from the tip of the spout — usually finger-tight, so try by hand first. If it's stuck, wrap it in a cloth to protect the finish and use pliers, turning clockwise as you face up at it (it loosens the "wrong" way because you're looking at it upside down).
Run the faucet with the aerator off. If the flow is now strong, the aerator was the restriction — confirmed. If it's still weak with the aerator removed, the clog is further in (cartridge, inlet screens, shutoff, or supply line).
Separate the aerator parts and look: white or chalky scale, sand, and grit in the screen confirm it. Rinse everything, poke debris out of the screen, and soak in vinegar if it's heavily scaled.

buildclothbuildpliers schedule10 min

handymanHow to fix it

Unscrew the aerator, rinse and clear the screen (soak in vinegar to dissolve heavy scale), or drop in an inexpensive matching replacement. Reinstall finger-tight and test the flow.

Plug the drain so no small parts fall in, then unscrew the aerator (by hand, or with cloth-wrapped pliers). Note the order the parts come out.
Rinse the screen and washer under running water and pick out grit. For chalky mineral scale, soak the parts in white vinegar for 10–15 minutes, then brush the screen clean.
If the screen is torn or too scaled to clear, replace the whole aerator — match the thread size (male vs female) and, if you like, the spray style. They cost only a few dollars.
Reassemble in the same order and thread the aerator back on finger-tight (a light snug with the cloth if it weeps). Run the faucet and confirm the flow is back to full.

schedule15 min savings$0–12

Replacement faucet aeratorMatch the thread size and gender (male vs female) to your spout — bring the old one or measure across the threads

gavel Check your province first AB: homeowner may do this · BC: homeowner may do this · ON: homeowner may do this · PE: homeowner may do this · QC: homeowner may do this
Owner cleaning or replacement of a faucet aerator is permitted across Canada; no permit for this like-for-like fixture repair.

handymanHow to fix it

With the water shut off, remove the handle and cartridge, flush the cartridge and the faucet's inlet screens clear of debris, or replace the cartridge with a brand-matched one, reassemble, and open the shutoffs slowly to test.

Close both under-sink shutoffs and open the faucet to relieve pressure and confirm the water is off. Note the faucet brand and model — cartridges are brand-specific.
Remove the handle and the retaining nut or clip, note the cartridge orientation (many have a keyed tab), and pull the cartridge straight up and out.
Flush the cartridge under running water and clear any grit; check the small inlet screens where the supply lines enter the faucet body and rinse those too. If the cartridge is scaled or worn, fit a brand-matched replacement in the same orientation.
Reassemble, open the shutoffs slowly, and run both hot and cold to confirm full flow and no drips.

schedule35 min savings$0–60

Replacement faucet cartridge (low-flow repair)Match the faucet brand and model — cartridges are not interchangeable between makers

gavel Check your province first AB: homeowner may do this · BC: homeowner may do this · ON: homeowner may do this · PE: homeowner may do this · QC: homeowner may do this
Owner cleaning or replacement of a faucet cartridge is permitted across Canada; whole-home pressure-regulator work is separate licensed plumbing work.

verifiedWhy this one goes to a pro

If the whole house is weak — not just this faucet — the fix is on the home's water main, not on any faucet. Diagnosing and adjusting or replacing a pressure-reducing valve, or clearing a restricted main, means cutting into the main supply and setting it correctly so every fixture is protected. Confirm the pattern yourself for free (run other taps and see if they're weak too), but have a licensed plumber do the work on the main.

Your notes travel with the request — what you saw, what you ruled out, when it started — so the pro arrives with a head start instead of a mystery.

handymanHow to fix it

With the shutoff closed, ease a kink out of the braided supply line, or replace it with a new one of the right length and connector size. Open the shutoff slowly and check the connections for weeping.

Close the shutoff for that line and open the faucet to relieve pressure. Have a small towel and bowl ready for the drips.
Inspect the braided hose behind the cabinet for a sharp kink and gently reshape it into a smooth loop. Turn the water back on and test — if flow returns, you're done.
If straightening it doesn't help, the inner liner may be collapsed or corroded. Unthread both ends and fit a new braided line of the same length and connector size (finger-tight, then a light snug with a wrench).
Open the shutoff slowly and watch both connections for weeping over a minute or two before leaving it.

schedule25 min savings$8–25

Braided faucet supply lineMatch the length and both connector sizes (commonly 3/8" compression at the valve, faucet-specific at the top)

gavel Check your province first AB: homeowner may do this · BC: homeowner may do this · ON: homeowner may do this · PE: homeowner may do this · QC: homeowner may do this
Owner replacement of a faucet supply line is permitted across Canada as a like-for-like fixture repair; no permit required.

sort

Why the list is in this order

We don’t sort by likelihood alone. We sort the way a good, honest tradesperson thinks: rule out the free, safe, common causes first. That’s why the cheap checks outrank the expensive repairs — and why anything dangerous gets a hard stop instead of a pep talk. The order exists to save you money, not to sell you anything.