Turn down water pressure at the main shutoff valve or pressure regulator

The fastest way to reduce water pressure is to adjust the pressure regulator, a bell-shaped or cylindrical device usually mounted on the main water line where it enters your home. If you have one, you can lower pressure by turning the adjustment screw on top counterclockwise. If you do not have a regulator, you can partially close the main shutoff valve — the lever or knob near where the water line enters the house — to restrict flow and drop pressure throughout the home.

Before you adjust anything, check your current pressure with a pressure gauge, which costs $10 to $20 at any hardware store and screws onto an outdoor faucet or washing machine outlet. Normal household pressure is 40 to 60 pounds per square inch (psi). Anything above 80 psi can damage pipes, fixtures, and appliances over time. Write down your starting pressure so you know how much you have changed.

If you have a pressure regulator, the adjustment is straightforward: locate the screw on top, turn it left (counterclockwise) a quarter turn, then recheck the gauge at an outdoor faucet. Make small adjustments — quarter turns — and wait a minute between each one so the system stabilizes. If you do not have a regulator and must use the main shutoff valve instead, turn it clockwise only slightly; closing it too far will reduce pressure everywhere and make showers weak.

Key Takeaways

  • A pressure regulator is the proper tool for lowering water pressure; it sits on the main water line and has an adjustment screw on top.
  • Normal household water pressure is 40 to 60 psi, and pressure above 80 psi can crack pipes and damage appliances.
  • Use a pressure gauge screwed onto an outdoor faucet to measure your current pressure before and after adjustment.
  • Make adjustments in quarter-turn increments and wait a minute between each one so the system can settle.
  • If you do not have a regulator, a plumber can install one for $300 to $500 and is the safer long-term solution than using the main shutoff valve.

Why high water pressure damages your home

Water pressure above 80 psi puts constant stress on pipes, joints, and seals. Over months or years, this pressure causes small cracks in copper or PVC lines, leading to slow leaks inside walls or under the foundation — damage you may not notice until water stains appear or your water bill spikes. Washing machine inlet valves, toilet fill valves, and water heater dip tubes all wear out faster under high pressure.

Fixtures also suffer. Faucet cartridges fail sooner, showerheads drip persistently, and dishwasher and refrigerator water lines can rupture without warning. Lowering pressure to the 50 to 60 psi range extends the life of every water-using appliance and reduces the risk of costly leaks.

Installing a pressure regulator if you do not have one

If your home has no regulator and you have been using the main shutoff valve to control pressure, a plumber should install one. The job takes one to two hours and costs between $300 and $500, depending on your location and the complexity of your plumbing setup. A regulator is a one-time investment that protects your entire system and gives you precise, stable control.

The regulator screws onto the main water line when ready after the shutoff valve and before any branch lines split off to different parts of the house. Once installed, you adjust it once and forget it — no daily fiddling with the main valve. If you are handy and comfortable with basic plumbing, some regulators can be installed as a DIY project, but most homeowners benefit from having a professional do it to may support proper placement and no leaks at the connection.

Adjusting pressure at individual fixtures

If you want to lower pressure only at one faucet or fixture rather than the whole house, you can install a flow restrictor or adjust the shutoff valve under that specific sink. Aerators — the screens at the tip of faucet spouts — can be unscrewed and cleaned or replaced with a lower-flow model. These changes do not affect pressure elsewhere in the home.

For a shower, you can replace the showerhead with a low-flow model rated at 2 gallons per minute (gpm) instead of the standard 2.5 gpm. Toilet fill valves often have a small adjustment screw or clip that limits how fast the tank refills; turning this down reduces noise and wear without affecting flush power. These fixture-level adjustments are useful if high pressure is a problem in only one area of your home.

When to call a plumber

Call a plumber if your pressure gauge reads consistently above 80 psi and you do not have a regulator. A professional can install one correctly and confirm that high pressure is not a sign of a deeper problem — occasionally, high pressure comes from a failing check valve or a blockage in the main line, not just the water company's supply pressure.

Also call a plumber if adjusting the regulator does not lower pressure, or if pressure drops suddenly and unevenly across the house. Sudden drops can mean a leak or a failing regulator, both of which need professional diagnosis. If you hear banging or hammering in the pipes when you turn off a faucet quickly, that is water hammer — a pressure spike that a regulator alone may not solve, and a plumber can install a water hammer arrestor to dampen it.

Checking pressure after adjustment

After you adjust the regulator or main valve, wait at least five minutes before rechecking pressure. The system needs time to stabilize, and a reading taken when ready after adjustment may be inaccurate. Screw the pressure gauge onto the same outdoor faucet you used for the first reading, turn the faucet on fully, and note the new psi.

If pressure is still too high, make another quarter-turn adjustment and wait again. If you have lowered it too far and pressure is now below 40 psi, turn the screw clockwise slightly to bring it back up. The goal is a steady 50 to 60 psi. Once you reach the right pressure, you can remove the gauge and store it for future checks — most homeowners only need to adjust pressure once unless they move or the regulator fails.

Frequently Asked Questions

What pressure should I set my regulator to?

Aim for 50 to 60 psi for most homes. This range protects pipes and appliances while providing adequate flow for showers and faucets. If you have a multi-story home or live at high elevation, you may need slightly higher pressure — a plumber can recommend the best setting for your situation.

Can I adjust the main shutoff valve instead of installing a regulator?

You can, but it is not ideal. Closing the main valve reduces pressure everywhere and can make showers weak or slow down dishwashers. A regulator maintains consistent pressure while limiting the maximum, so it is a better long-term solution. If you must use the main valve temporarily, turn it only slightly and monitor your pressure.

Will lowering water pressure reduce my water bill?

Slightly. Lower pressure means less water flows out of faucets and showerheads per minute, so you use less water over time. The savings are modest — usually $5 to $15 per month — but they add up, and the real benefit is protecting your pipes and appliances from damage.

What if I cannot find my pressure regulator?

Not all homes have one. Check the main water line where it enters the house, near the shutoff valve. If you see no bell or cylinder-shaped device, you do not have a regulator. A plumber can install one, or you can temporarily manage pressure by slightly closing the main shutoff valve until a regulator is installed.

Does lowering water pressure affect hot water?

No. Pressure adjustment happens on the main line before water splits into hot and cold branches. Lowering pressure affects both equally, so your hot water will flow at the same reduced rate as your cold water.