Start with the pressure regulator and main shutoff valve
Low water pressure usually comes from one of three places: your municipal supply, a faulty pressure regulator, or a blockage in your pipes. The fastest fix is often your pressure regulator—a bell-shaped valve typically mounted on the main water line where it enters your home, usually in the basement, crawl space, or under the kitchen sink.
A pressure regulator reduces incoming pressure to a safe level for your home's pipes. If it fails or is set too low, your pressure drops. Most regulators have an adjustment screw on top. Turn it clockwise to increase pressure, but do not exceed 80 pounds per square inch (psi)—higher pressure damages fixtures and pipes. You can rent or buy a pressure gauge at a hardware store for about $10 to $20 to check your current pressure before and after adjusting.
If you do not have a regulator or cannot locate it, call your water utility first. They can tell you whether low pressure is a problem on their side of the meter. If it is, they will fix it at no cost. If the problem is in your home, you know to look at your own system.
Key Takeaways
- A faulty or incorrectly set pressure regulator is the most common cause of low water pressure and can often be adjusted with a straightforward wrench.
- Check your main shutoff valve to confirm it is fully open—a partially closed valve cuts pressure throughout your entire home.
- Mineral buildup in aerators and showerheads can be cleaned by soaking in vinegar, restoring pressure to individual fixtures without replacing them.
- Corrosion or sediment inside old galvanized pipes may require professional inspection, but a plumber can diagnose this in one visit.
- If only one fixture has low pressure, the problem is local to that fixture; if the whole house is affected, the problem is on the main line.
Check whether your main shutoff valve is fully open
Your main shutoff valve controls water flow into your entire home. If it is partially closed, pressure drops everywhere. The valve is usually located near your water meter, often in a basement, utility room, or outside in a meter box.
There are two common types. A ball valve has a lever handle that should point in line with the pipe when fully open—if it points perpendicular to the pipe, it is closed. A gate valve has a round wheel handle; turn it counterclockwise until it stops to open it fully. If the handle is stiff or will not turn, do not force it—call a plumber, because forcing it can break the valve.
After opening the valve fully, wait a few minutes and check your pressure. This is free and takes five minutes, so it is always worth trying first.
Clean aerators and showerheads clogged with mineral deposits
If only one or two fixtures have low pressure while others work fine, the problem is local to those fixtures. Mineral buildup inside aerators (the screens on faucet spouts) and showerhead holes is the most common cause and is straightforward to fix yourself.
Unscrew the aerator or showerhead by hand or with a wrench. Soak it in a bowl of white vinegar for two to four hours, or overnight for heavy buildup. Use an old toothbrush to scrub away deposits, then rinse thoroughly under running water and screw it back on. If the holes are still clogged, use a thin wire or needle to clear them individually.
This costs nothing if you have vinegar at home and takes about five minutes of hands-on time. If soaking does not work, the aerator or showerhead may be damaged and need replacement—a new one costs $5 to $15.
Look for leaks that signal pipe damage or corrosion
Leaks anywhere in your system reduce pressure because water escapes before reaching your fixtures. Check under sinks, in the basement, and along visible pipes for drips or wet spots. Even a small leak wastes water and lowers pressure.
If you find a leak on a flexible supply line (the hose connecting a fixture to the shutoff valve), you can often replace it yourself—they cost $5 to $20 and take ten minutes to swap out. If the leak is on a rigid copper or galvanized steel pipe, or if you cannot locate the source, call a plumber. They can use a pressure test or water meter reading to confirm a leak exists and locate it.
Corrosion inside old galvanized steel pipes also reduces pressure over time. If your home was built before 1980 and has galvanized pipes, and pressure is low throughout the house, internal corrosion may be the cause. A plumber can confirm this by checking pressure at different points in your system. Fixing it usually means replacing the affected section or the entire main line, which is a larger job.
Install a pressure booster pump if pressure is chronically low
If your municipal supply pressure is genuinely low (below 40 psi) and your regulator, shutoff valve, and pipes are all in good condition, a pressure booster pump can increase flow throughout your home. These pumps sit on your main water line and use an electric motor to push water at higher pressure.
A basic booster pump costs $300 to $800 installed, depending on the model and your plumber's labor rate. They are most useful in rural areas with low municipal pressure or in homes on hilltops where gravity reduces pressure. Before buying one, have a plumber measure your actual pressure and confirm that boosting it will solve your problem—sometimes low pressure is caused by undersized pipes or a failing water heater, which a pump cannot fix.
Booster pumps require electricity and occasional maintenance, so they are not a first choice. But if you have ruled out every other cause and pressure is still too low, they work reliably.
Diagnose whether the problem is in your home or the municipal supply
The fastest way to narrow down the cause is to check pressure at your water meter. Turn on a cold-water tap closest to the meter and let it run for 30 seconds, then attach a pressure gauge to a nearby outdoor faucet or hose bib. If pressure is below 40 psi, the problem is likely on the utility's side. If it is above 60 psi, the problem is in your home.
Call your water utility and report low pressure. They will check their lines and may send someone to test at your meter for free. If they find a problem on their side, they fix it. If they find normal pressure at the meter, the problem is definitely in your home, and you can focus on your regulator, shutoff valve, and pipes.
Keep a record of the date and time you tested, and what pressure you found. This information helps a plumber diagnose the problem faster if you need to hire one.
When to call a plumber
Call a plumber if you have adjusted the pressure regulator and opened the shutoff valve, but pressure is still low throughout your home. They can test your system in about an hour and identify whether the problem is corrosion, a failed regulator, a hidden leak, or undersized pipes.
You should also call a plumber if you find a leak you cannot fix yourself, if your main shutoff valve is stuck or leaking, or if you are uncomfortable working with your water system. A service call typically costs $100 to $200, and a diagnosis takes 30 to 60 minutes. If repair is needed, ask for an estimate before they start work.
Frequently Asked Questions
Can high water pressure damage my pipes?
Yes. Pressure above 80 psi stresses pipes, fittings, and appliances over time, leading to leaks and premature failure. If your pressure regulator is broken or missing, have it repaired or installed. A plumber can add one for $200 to $400 if your home does not have one.
Why is my water pressure low only in the morning?
Morning low pressure often means the utility is drawing heavily from the system during peak hours. It usually returns to normal by mid-morning. If it happens every morning and lasts more than an hour, call your utility to report it. If it happens only in your home, the problem may be a check valve or pressure tank issue, which a plumber can diagnose.
Does a water softener reduce pressure?
A water softener can slightly reduce pressure if it is undersized or clogged with sediment. If you installed one recently and pressure dropped, have the installer check it. If pressure was already low, the softener did not cause it, but a plumber can confirm this.
What pressure should my home have?
Normal household water pressure is between 40 and 80 psi. Below 40 psi, showers and washing machines work poorly. Above 80 psi, you risk leaks and damage. Most homes are set to 50 to 60 psi by the pressure regulator.
Can I increase pressure by replacing my water heater?
No. A water heater does not affect pressure—it only heats water that is already flowing. If pressure is low only for hot water, the problem is in the hot water line or the heater's inlet valve, which a plumber can check.