Leaks & Pipes · plumbing advice
Low Water Pressure in the House: 7 Causes, Ranked by Likelihood
Low water pressure in one tap means something different from low pressure everywhere. Here's how Oklahoma plumbers narrow it down before opening a wall.
The first question to answer is not why the pressure is low. It is whether the pressure is low everywhere or just at one fixture. Those are two entirely different problems and the diagnosis splits immediately.
If it is only one tap
Clogged aerator. The little screen on the end of a faucet catches mineral grit, and in Oklahoma there is plenty of it. Unscrew it, soak it in vinegar overnight, scrub and refit. This fixes more complaints than anything else on this list.
Failing cartridge. If the aerator is clean and flow is still weak, the cartridge inside the faucet body is worn or blocked. That is a faucet repair, not a plumbing-system problem.
Partly closed angle stop. The shutoff valve under the sink may have been knocked or never fully opened after previous work.
If it is the whole house
Pressure regulator failing. Many homes have a pressure reducing valve where the main enters. They last ten to fifteen years and when they go, pressure either drops away or spikes. Replacing one is a straightforward job.
Partly closed main valve. After any plumbing work, the main sometimes gets left three-quarters open. Worth checking before anything else.
Corroded galvanised pipe. If the house still has galvanised steel supply lines, the inside diameter narrows with rust until flow chokes. Pressure that has dropped gradually over years, rather than suddenly, points here. The fix is repiping.
A leak in the main line. If pressure dropped suddenly and there is a damp or unusually green strip in the yard, water is escaping before it reaches the house. That is a water line repair and worth acting on quickly.
A slab leak. Falling pressure with a warm patch on the floor and a rising water bill is the classic combination. See slab leak repair.
The five-minute test that tells you a lot
Turn every fixture in the house off. Go to the meter and watch the dial or leak indicator. If anything is moving, water is going somewhere it should not be, and you have a leak rather than a restriction. That single test separates half the causes above from the other half.
Not sure which side you are on? Call (833) 435-9778 and describe it. Our dispatcher can usually narrow it down on the phone before anyone drives out.
Need this sorted today? Call (833) 435-9778. We answer 24/7 across Oklahoma, quote a flat price before starting, and charge the same rate at night and on weekends.
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