Low Water Pressure in the Whole House? Here's What's Causing It

Weak showers, a washing machine that takes forever to fill, a kitchen faucet that trickles — low water pressure in the house is frustrating, and it often points to a problem that is getting worse. Here is how our plumbers diagnose it across Pennsylvania.

First: Is It One Fixture or the Whole House?

If only one faucet or shower is weak, the fix is usually local — a clogged aerator, a failing cartridge or a partially closed shut-off valve under the sink. Our faucet repair & installation and shower & tub repair services handle those quickly. If every fixture is weak, keep reading.

Whole-House Low Pressure: The Usual Suspects

1. Failed pressure reducing valve (PRV). Many homes have a bell-shaped regulator where the main line enters. When it fails, pressure can drop (or spike). Replacement is a straightforward job.
2. Main shut-off valve partially closed. Old gate valves can fail internally and restrict flow even when they look open.
3. Corroded galvanized pipes. Homes built before the 1970s often still have galvanized steel supply lines. Rust builds up inside until the pipe is nearly closed. The only permanent fix is whole house repiping.
4. Leaking water service line. A leak between the street and the house steals pressure and wastes water. Look for a soggy spot in the yard. See water line repair.
5. Clogged water softener or whole-house filter. A filter that has not been changed, or a softener with fouled resin, can choke flow.
6. Municipal supply issues. Occasionally the problem is at the main. We can measure incoming static pressure to tell the difference.

How We Diagnose It

We attach a gauge to an outdoor spigot to measure static pressure (ideal range is 45–65 PSI), then check flow under load. From there we inspect the PRV, main valve, visible piping and the water meter for movement that indicates a hidden leak. Our leak detection team can pinpoint underground leaks without digging.

Low water pressure help is available in Wilkes-Barre, Lebanon, Bethel Park and every other city we serve. Call (888) 809-6756.