Low Water Pressure in Your Home: Common Causes and Fixes

Low water pressure can turn a morning shower into a frustrating trickle and make simple tasks like filling a pot or running the dishwasher take twice as long. The cause could be as simple as a clogged aerator on one faucet — or as serious as a failing main water line. Knowing how to narrow down the source can save you time and help you describe the problem clearly when you call for .

The first step is to determine whether the low pressure affects one fixture — one sink, one shower, one toilet — or the entire home.

The problem is likely local — a clogged aerator, a partially closed shut-off valve, a failing cartridge, or buildup in the fixture itself. Clean the aerator first by unscrewing it from the faucet and rinsing out any debris. If that does not fix it, the cartridge or valve may need replacement.

The problem is likely in the main supply line, the pressure regulator, or the water heater. Whole-house low pressure usually needs professional diagnosis.

### Clogged aerators and shower heads

Mineral deposits from hard water can clog the small openings in faucet aerators and shower heads over time. Unscrew the aerator or shower head and soak it in vinegar for a few hours to dissolve the deposits.

### Partially closed main shut-off valve

If the main shut-off valve was not fully opened after a repair or during a water shut-off, pressure throughout the house will be low. Check that the valve is turned all the way open.

### Failing pressure regulator

Most homes have a pressure regulator where the water line enters the house. If it fails, pressure can drop throughout the home — or spike dangerously high. A plumber can test the pressure and replace the regulator if needed.

### Corroded or narrowed pipes

In older Los Angeles homes with galvanized steel pipes, internal corrosion can narrow the pipe diameter over decades until water barely passes through. This usually affects the whole house and gets worse over time. The fix is repiping — replacing the old pipes with copper or PEX.

### Hidden leak

A leak in the main supply line or inside a wall can drop pressure by letting water escape before it reaches your fixtures. If you also have a high water bill or hear running water, a inspection can confirm whether a leak is the cause.

### Municipal supply issues

Sometimes the problem is not in your home at all. If your neighbors also have low pressure, the municipal supply may be affected by a water main break, maintenance work, or high demand. Call your water utility to check.

Call for when low pressure affects multiple fixtures or the whole house, when cleaning aerators does not fix a single-fixture problem, when you also notice water stains, high bills, or running water sounds, or when the home has original galvanized pipes that may be corroded from the inside.