Where your water pressure comes from and why it drops

Water pressure in your home comes from one of two sources: either the municipal water line that feeds your house, or a well pump if you're on a private well. The pressure naturally decreases as water travels through pipes, especially if those pipes are old, corroded, or undersized. Pressure also drops when multiple fixtures run at once—a shower and a washing machine running together will reduce pressure at both.

Before you try to increase pressure, check whether the problem is everywhere in your house or only at certain fixtures. Low pressure at one sink might mean a clogged aerator (the screen at the faucet tip). Low pressure everywhere suggests either a problem with your main line, a failing pressure regulator, or sediment buildup in your pipes.

Key Takeaways

  • Clean aerators and showerheads first—they clog with mineral deposits and are the easiest fix.
  • Check your pressure regulator (a bell-shaped valve near where the water line enters your house) and adjust it upward if the pressure is below 50 PSI.
  • If you have a well, a failing pressure tank or pump may need professional inspection or replacement.
  • Sediment buildup in old pipes requires either flushing the line or, in severe cases, pipe replacement by a plumber.
  • Municipal water pressure is controlled by your city—you cannot increase it yourself, but you can install a pressure booster pump.

Clean aerators and showerheads first

The quickest fix is often the simplest. Aerators—the small screens at the end of faucets—collect mineral deposits and sediment over time. Unscrew the aerator by hand (turn counterclockwise), soak it in white vinegar for 30 minutes to dissolve mineral buildup, then rinse it under running water and screw it back on. Do the same with showerheads.

If the aerator is too corroded to clean, replace it with a new one from any hardware store for a few dollars. Showerheads are equally cheap and straightforward to swap out. This step alone restores pressure in many homes.

Adjust your pressure regulator if you have one

Most homes on municipal water have a pressure regulator—a bell-shaped or cylindrical valve usually located near the water meter, where the main line enters your house. It reduces incoming pressure to a safe level (typically 40 to 60 PSI). If your pressure is too low, you can adjust it upward.

First, buy an inexpensive water pressure gauge from a hardware store and screw it onto an outdoor faucet or a hose bib. Turn on the faucet fully and read the gauge. If the pressure is below 50 PSI, the regulator may need adjustment. Look for a screw or bolt on top of the regulator. Turn it clockwise (a quarter turn at a time) to increase pressure, then recheck with the gauge. Stop when you reach 60 PSI—higher pressure can damage pipes and appliances. If the regulator will not adjust or pressure remains low, the regulator itself may have failed and needs replacement by a plumber.

Check for leaks and sediment in your pipes

A hidden leak in your main line will reduce pressure throughout the house. Look for wet spots in your yard, unusually high water bills, or the sound of running water when no fixtures are on. If you suspect a leak, call a plumber—they can locate it with specialized equipment.

Sediment buildup inside old pipes also reduces pressure. If your house is more than 40 years old and pressure has dropped gradually, sediment may be the cause. You can try flushing the line by turning off the main water valve, opening all faucets in the house, then turning the main valve back on and letting water run for a few minutes. This sometimes dislodges sediment. If pressure does not improve, a plumber can flush the line with higher pressure or, in severe cases, recommend pipe replacement.

Install a pressure booster pump for low municipal pressure

If your city's water pressure is naturally low (below 40 PSI) and your regulator is already set as high as it will go, a pressure booster pump can increase pressure throughout your house. These pumps are installed on the main water line after the meter and automatically turn on when pressure drops below a set point.

Booster pumps range from a few hundred to over a thousand dollars depending on size and type. A plumber can assess whether your home needs one and install it. This is a permanent solution but requires professional installation and occasional maintenance.

What to do if you have a well

Well systems use a pressure tank and pump to maintain pressure. If pressure is low, the tank may have lost air charge, the pump may be failing, or the tank may be waterlogged. You can check the air pressure in the tank with a tire gauge at the air valve (usually on top of the tank). The pressure should be about 2 PSI below your system's cut-in pressure—typically around 28 to 30 PSI for a 40/60 system.

If the air pressure is too low, you can add air with a compressor. If the tank is waterlogged or the pump is not building pressure, call a well service technician. Pressure tank and pump repairs or replacements require professional work.

When to call a plumber

Call a plumber if pressure remains low after cleaning aerators and checking the regulator, if you suspect a leak, if your pressure regulator is broken, or if you have a well system with low pressure. A plumber can measure pressure at different points in your system, identify the real cause, and recommend the right fix—whether that is a booster pump, pipe flushing, or component replacement.

Do not ignore very low pressure (below 20 PSI) for long. It can strain your water heater and other appliances, and it may indicate a serious problem like a main line break.

Frequently Asked Questions

Can I increase water pressure if I rent?

You can clean aerators and showerheads yourself. For anything else—adjusting a regulator, installing a booster pump, or investigating low pressure—you need permission from your landlord. Contact them and ask them to have a plumber investigate. They are responsible for maintaining the water system.

Is high water pressure bad for my pipes?

Yes. Pressure above 80 PSI can damage pipes, fittings, and appliances like water heaters and washing machines over time. A pressure regulator keeps pressure in the safe range. If your regulator is broken and pressure is very high, have it replaced soon.

Why is pressure low in only one room?

A single room with low pressure usually means a clogged aerator or showerhead, a partially closed shut-off valve under that sink, or a leak in that branch of pipe. Start by cleaning the aerator. If that does not help, check the shut-off valve under the sink—it should be fully open (handle parallel to the pipe). If both are fine, a plumber can check for a leak in that line.

How much does it cost to fix low water pressure?

Cleaning aerators is free. A new aerator or showerhead costs a few dollars. Adjusting a regulator costs nothing if you do it yourself. A plumber visit to diagnose the problem typically costs 75 to 150 dollars. A booster pump installation ranges from 500 to 2000 dollars depending on the system. A pressure tank replacement for a well can cost 800 to 2500 dollars.

Will a water softener increase pressure?

No. A water softener removes minerals but does not increase pressure. In fact, it may slightly reduce pressure because water passes through an extra filter. If you have both low pressure and hard water, address them separately—fix the pressure first, then consider a softener if mineral buildup is a problem.