Home › Low Water Pressure at One Tap Only
Low water pressure · diagnosed first
Low Water Pressure at One Tap Only
If the rest of the house is fine, you almost certainly do not need a plumber. Four things cause this, and three of them cost nothing to fix.
Free to homeowners in Low Water Pressure at One Tap Only — the contractor pays us for the introduction, you never do.
The short answer
One weak tap with the rest of the house normal almost never needs a plumber, because the supply into the property is fine by definition and the restriction is at that fixture. Four things cause it, in order of likelihood, and three of them cost nothing to put right.
What this site is
PressureTrace is a referral service, not a plumbing contractor. We connect homeowners with independent contractors. Contractors are required to hold whatever credential their state or municipality demands. Every state page sets out who licenses plumbers there and where to check, so you can confirm before work begins. We do not perform plumbing work, we do not set prices, and we never charge homeowners anything — the contractors in our network pay us when we route them a call.We would rather tell you this plainly than route you a call you did not need. When one fixture is weak and everything else is normal, the supply into the property is fine by definition — the restriction is at that fixture.
In order of likelihood
The aerator
The small screen in the end of the spout catches grit and scale. It is the single most common cause and it is free to fix. Unscrew it, soak it, refit it.
The fixture shut-off
Under the sink, or behind the toilet, there is a small valve for that fixture alone. If someone has worked on it recently it may not be fully open. Turn it counter-clockwise until it stops.
The cartridge or the supply hose
On a mixer tap a worn cartridge restricts flow, often on one temperature only. Braided supply hoses can also kink behind a vanity where you cannot see them.
Only the hot side
If cold is strong and hot is weak at every fixture, that is not a fixture problem at all — it points at the water heater or its shut-off. That has its own page.
When it is worth calling after all
If you have cleaned the aerator, opened the valve fully and the fixture is still weak, the restriction is in the branch pipe feeding it. That is inside the wall, and it is a contractor's job.
Still not sure whether it is the whole house or one fixture?That distinction decides who you need and what it costs, and it takes one conversation. We route you to a contractor who covers your ZIP code, you are never charged, and if the answer turns out to be an aerator we will say so. And it need not be pressure — this number takes any plumbing problem.
Call (866) 838-2750