Check your water pressure with a straightforward gauge
You can measure your home's water pressure in about five minutes using a water pressure gauge, which costs $10 to $25 at any hardware store. Screw the gauge onto an outdoor faucet or a laundry room spigot—the same way you would attach a garden hose. Turn the faucet on fully and read the number on the dial. That number, measured in pounds per square inch (psi), is your water pressure.
Most homes run between 40 and 80 psi. Anything below 40 psi will feel like a weak shower; anything above 80 psi can damage appliances and cause pipes to leak. If your reading falls outside this range, you have a real problem to solve, but at least you now know what you are dealing with.
The gauge itself is not fancy. Buy one with a dial face you can read easily—avoid tiny digital ones unless you have good eyesight. Keep it in a drawer after you use it; you may need to check again if your pressure changes.
Key Takeaways
- A water pressure gauge screws onto any outdoor faucet and gives you a reading in psi within seconds.
- Normal household water pressure ranges from 40 to 80 psi; readings outside this range signal a problem worth investigating.
- Pressure that is too low affects shower flow and washing machine fill time; pressure that is too high damages pipes and appliances.
- You can buy a gauge for under $25 and reuse it whenever you need to check your pressure again.
Where to attach the gauge for the most accurate reading
Use an outdoor faucet or a laundry room spigot rather than a kitchen or bathroom sink. Outdoor faucets are usually connected directly to the main water line with fewer twists and turns, so they give you the true pressure coming into your house. Kitchen and bathroom faucets often have aerators (the screen at the tip) that reduce flow and can give you a false low reading.
If you have a basement or crawl space, a hose bib down there is even better—it is closer to where the water enters your home. Turn off all other water use in the house before you measure. Running a washing machine or flushing a toilet while you check will lower the reading and confuse your results.
What happens if your pressure is too low
Low pressure—below 40 psi—makes showers feel weak and washing machines fill slowly. You may notice that you cannot run the dishwasher and shower at the same time without one of them dropping to a trickle. Low pressure can also mean sediment is clogging your pipes or that you have a slow leak somewhere in your system.
Start by checking whether the problem is only at one faucet or throughout the house. If it is only one faucet, the aerator is probably clogged. Unscrew the screen at the tip, rinse it under running water, and screw it back on. If the whole house has low pressure, the issue is either in your meter, your main shutoff valve, or your pipes themselves—all things a plumber can diagnose.
What happens if your pressure is too high
High pressure—above 80 psi—is harder on your plumbing than most people realize. It stresses pipe joints, causes water heater relief valves to open and leak, and shortens the life of washing machine hoses and dishwashers. You may hear banging in the pipes when you turn off a faucet quickly; that sound is the shock wave from high-pressure water slamming to a stop.
If your pressure is consistently above 80 psi, ask your water company whether the pressure on the street is high or whether something in your home is causing it. If the street pressure is high, you may need a pressure regulator—a device that screws onto your main water line and reduces pressure to a safe level. A plumber can install one for a few hundred dollars. If the problem is in your home, a plumber can find and fix it.
Pressure that changes throughout the day
Water pressure naturally rises and falls depending on how much water your neighborhood is using. Early morning and evening—when people shower and cook—pressure tends to be lower. Middle of the day is usually higher. This is normal and not something you need to fix.
If your pressure swings wildly—from 30 psi to 90 psi in the same day—that is not normal. Extreme swings suggest a problem with your pressure regulator (if you have one), a failing water heater, or a leak that is opening and closing. Write down the times when pressure is highest and lowest, and share that information with a plumber or your water company.
Testing pressure at different points in your home
If you suspect a leak or a blockage, you can test pressure at multiple faucets. Attach your gauge to the outdoor faucet, note the reading, then move to a kitchen sink, a bathroom sink, and a laundry room spigot. All readings should be within 5 psi of each other. A big drop at one location suggests a clog or leak in the pipe leading to that faucet.
Test each one with the same faucet fully open and no other water running in the house. If one faucet reads much lower than the others, that faucet's aerator is probably clogged. If a whole section of your home reads lower—say, the upstairs bathroom and the upstairs shower both read 10 psi lower than downstairs—you may have a leak in the wall or a blockage in the line serving that area.
When to call a plumber about your pressure reading
Call a plumber if your pressure is below 40 psi and cleaning aerators does not fix it, or if it is above 80 psi and stays there. Also call if pressure drops suddenly without any change in your water use, or if you see water pooling in your yard or basement—both signs of a leak. A plumber can run a pressure test on your whole system and pinpoint where the problem is.
If your water company is your water source (not a well), you can also call them to ask whether the street pressure is normal. They may send someone to check the meter or the main line at no cost. If you have a well, a well contractor can test the pressure tank and pump.
Frequently Asked Questions
Do I need a special gauge or will any pressure gauge work?
Buy a gauge labeled for water pressure, not air pressure or gas pressure. Water pressure gauges are inexpensive and widely available. Look for one with a dial that goes up to at least 100 psi so you can see the full range of your home's pressure.
Can low water pressure mean I have a leak?
Yes, a slow leak can lower your pressure over time. If your pressure dropped suddenly and cleaning aerators did not help, you may have a leak in a hidden pipe. A plumber can use a pressure test to confirm whether a leak is present and where it might be.
Is 100 psi too high for a home?
Yes. Anything above 80 psi puts stress on pipes and appliances. At 100 psi, you risk damage to your water heater, washing machine, and pipe joints. If your gauge reads that high, a pressure regulator is a good investment.
What if my pressure is perfect but my shower still feels weak?
The problem is probably a clogged aerator or showerhead, not your water pressure. Unscrew the showerhead, soak it in white vinegar for an hour to dissolve mineral buildup, and rinse it thoroughly. If that does not work, replace it with a new one.
How often should I check my water pressure?
Check it once a year or whenever you notice a change in water flow. If you have had plumbing work done, check it afterward to make sure nothing shifted. If your pressure has been stable for years, you do not need to check often.