Quick answers

  • One fixture or the whole house? Low pressure at one sink points to a local clog, aerator, or closed shutoff valve. Low pressure everywhere means the problem is further up the line.
  • Check the shut-off valve first: A partially closed shut-off valve is one of the most common causes and takes thirty seconds to check. Either the main shutoff valve to your home or the shutoff valves at the fixture that have low pressure.
  • PRV failure: A pressure reducing valve that goes bad can drop whole-house pressure overnight. Most homes have one where the main line enters the house.
  • Older home? Galvanized pipes corrode from the inside and slowly choke off water flow. Low pressure that has gotten worse over years usually points here.
  • Could be a leak: A sudden pressure drop with no other explanation can mean a pipe has burst or is leaking somewhere hidden.

Weak trickle of water coming from a kitchen or bathroom faucet. Simple, clear photo that matches the search intent immediately.

Low water pressure that shows up out of nowhere is your plumbing telling you something changed. It might be a simple fix you can handle in a few minutes. It might be a sign of a bigger problem that needs a plumber. The first step is figuring out whether the low pressure is in one spot or everywhere in the house.

Is it one fixture or the whole house?

This is the most important question to answer first. Go check two or three other faucets in the house.

If the pressure is fine everywhere else, the problem is local to that one fixture. A clogged aerator is the most common cause. Unscrew the tip of the faucet, rinse the screen, and screw it back on. For a showerhead, soak it in white vinegar overnight to clear mineral buildup. That fixes most single-fixture pressure problems.

If the pressure is low at every faucet in the house, keep reading. That points to something further up the line.

Check the main shut-off valve

Before calling anyone, find your main water shut-off valve. In most Winston-Salem and Kernersville homes it is in the crawlspace, near the water meter, or where the main line enters the house. Make sure it is fully open. A valve that is even halfway closed can cut pressure significantly. This happens more than you would think, especially after recent plumbing work or if someone bumped it.

If you are not sure where your shut-off valve is or whether it is fully open, our guide on shut-off valves walks through how to find and check it.

PRV failure

Most homes have a pressure reducing valve, or PRV, installed where the main water line comes into the house. Its job is to bring street pressure down to a safe level for your pipes, usually between 45 and 80 PSI. When a PRV starts to fail, it can drop pressure well below that range and affect every faucet and fixture at once.

PRVs typically last 10 to 15 years. If yours is older than that and pressure has dropped suddenly, it is a strong suspect. A plumber can test your pressure at the line and confirm whether the PRV is the problem. Replacing one is a straightforward repair.

PRV (pressure reducing valve) installed on a main water line, with label pointing to it. A real job-site photo or clean diagram both work well here.

Corroded pipes in older homes

If you live in an older home in Winston-Salem, Kernersville, or Greensboro and your pressure has been getting worse slowly over time rather than dropping suddenly, galvanized steel pipes are likely the cause. Galvanized pipes corrode from the inside out. The rust and buildup narrow the inside of the pipe over decades until water can barely get through. Think of it like a clogged artery.

There is no cleaning fix for this. Once galvanized pipes have corroded enough to affect pressure, the only real solution is repiping with modern materials like copper or PEX. It is a bigger job but it solves the problem permanently and removes a serious risk of pipe failure down the road.

Low pressure combined with brown or rust-colored water when you first turn on the tap is a clear sign galvanized pipes are to blame.

A leak somewhere in the house

A sudden drop in water pressure with no obvious cause can mean a pipe is leaking or has burst somewhere hidden in your walls, under your slab, or in your crawlspace. A leak pulls water out of the line before it reaches your fixtures, and pressure drops as a result.

If you suspect a leak, check your water meter with all fixtures turned off. If the meter is still moving, water is going somewhere it should not be. Do not ignore this one. Hidden leaks cause serious damage fast. See our guide to spotting hidden water leaks for the full checklist.

Could be the municipal supply

Sometimes low pressure is not your problem at all. If your neighbors are having the same issue, the city supply line may be the cause. Winston-Salem Utilities and other local water providers occasionally have pressure drops during main breaks, high-demand periods, or repair work. Call your water provider to check before spending time troubleshooting inside the house.

When to call a plumber

Call a plumber if pressure is low throughout the whole house and the shut-off valve is fully open, if you suspect a PRV failure, if you have galvanized pipes and pressure has been getting worse, or if you cannot find the cause and the meter is still moving with everything turned off. Low pressure that comes on suddenly and has no easy explanation usually means something needs to be diagnosed before it gets worse.

We serve Winston-Salem, Kernersville, Greensboro, and the surrounding area. Call us and we will figure out what is going on. 336-203-2348