Why Is My Water Pressure Too High or Too Low?

If your faucets barely trickle or your pipes seem to shake under pressure, you may be dealing with a water pressure problem. Both high and low water pressure can damage plumbing fixtures, waste water, or make everyday tasks frustrating. The first step is figuring out whether the issue is pressure, flow, or both.

TL;DR

• Normal residential water pressure is between 50 and 70 psi.
• High pressure can damage plumbing fixtures and appliances.
• Low pressure may be caused by supply issues, pipe corrosion, or blockages.
• Static pressure and water flow are different problems.
• A professional plumber can diagnose and fix pressure issues safely.

How to check your water pressure

Improper water pressure is a common plumbing problem. You can measure your home’s static water pressure using a simple pressure gauge, available at most hardware stores.

The gauge attaches to an exterior hose bib or a washing machine water line. Once connected, open the valve and read the pressure. Keep in mind that second-floor fixtures typically read about 8 psi lower than first-floor fixtures.

What is the correct water pressure?

For most homes, water pressure should fall between 50 and 70 psi. Plumbing fixtures are designed to handle up to 80 psi. Pressure above that level can shorten the life of faucets, valves, and appliances.

If pressure drops well below 50 psi, you may experience weak water flow, especially when multiple fixtures are in use.

What to do if water pressure is too high

If your water pressure is too high, the solution is usually a pressure reducing valve. This valve is typically located near the main water shutoff and keeps household pressure at a safe, consistent level.

If your home does not have a pressure reducing valve, one should be installed by a professional plumber. This is not a DIY repair.

What to do if water pressure is too low

If pressure is low, start by contacting your local water supplier to confirm whether the pressure is normal for your area. If it is, the next option may be installing a water pressure booster pump.

Booster pumps come in several designs and price ranges, but proper installation is critical. This work should always be handled by a professional plumber.

Water pressure vs. water flow

Sometimes the issue is not pressure at all, but water flow. If pressure readings are normal but water output is weak at certain fixtures, the problem is usually inside the plumbing system.

Common causes include clogged faucet aerators or shower heads. These can often be cleaned by soaking them overnight in a mixture of white vinegar and water.

When poor water flow means bigger problems

If all fixtures have poor flow, the issue may be corroded galvanized steel pipes. These pipes were common in older homes but typically last only about 40 years. As corrosion builds up inside the pipe, water flow is restricted.

The only permanent solution is replacing galvanized pipes with modern materials such as copper or PEX.

How pipe size affects water flow

Larger diameter pipes help maintain dynamic water pressure, which is the pressure available when fixtures are in use. While pipe diameter does not affect static pressure, it does reduce pressure drops when water is flowing.

In some cases, increasing pipe diameter in key sections of the system can noticeably improve overall water flow.