Low Water Pressure Through the Whole House?
Whether it is one fixture or every faucet tells you almost everything. Find the likely cause and whether it is a five-minute fix or a plumbing repair.
Treat It as Urgent If You See This
Treat it as urgent if you see:
- A sudden pressure drop with no explanation (possible burst or major leak)
- Wet spots, warm floors, or the sound of running water when everything is off
- Discolored or gritty water alongside the pressure drop
- A water bill that jumped without a change in usage
- No water at all at one or more fixtures
Low pressure is rarely an emergency on its own — but paired with a spinning meter, a warm spot on the floor, or water where it should not be, it points to an active leak. Shut off the main and call a plumber rather than waiting to see if it gets worse.
Quick answer
First figure out the scope: one fixture, hot only, or the entire house. One fixture is usually a clogged aerator. Hot-water-only points to the water heater or its shutoff. Whole-house pressure loss points to the main valve, the pressure regulator, corroded supply piping, or a leak. Check that the main and meter valves are fully open before anything else — it is free and it is often the answer. This page is educational information, not a diagnosis of your plumbing.
Possible causes
Clogged aerators or showerheads
Mineral scale collects in the screens. If only one fixture is weak, start here.
Failing pressure regulator
The PRV near the main shutoff wears out and slowly strangles pressure house-wide.
Partially closed main or meter valve
A valve left half-open after work on the line is a common and free fix.
Corroded galvanized supply pipes
Older galvanized lines narrow with rust until flow drops noticeably.
Hidden leak in the supply line
A slab or yard leak bleeds pressure and often shows up first on the water bill.
Water heater issues
If only hot water is weak, sediment or a failing shutoff at the heater is the usual culprit.
Municipal supply or well pump problems
City work, a pressure tank losing charge, or a weak well pump affects everything at once.
Whole-house filter overdue
A saturated filter cartridge chokes flow gradually until nobody remembers when it changed.
How this project is usually classified
General guidance for this problem type — not a diagnosis of your home.
- Typical urgency
- Soon — within weeks
- Safety risk
- Low safety risk
- DIY suitability
- DIY friendly
- Cost level
- Low cost
- Repair option
- Clean aerators, then test static pressure before replacing the PRV.
- Replacement option
- Repipe when scaling in galvanized lines is the cause.
- Typical timeline
- DIY checks in under an hour; PRV replacement a half day
- Contractor type
- plumbing
What you can safely check yourself
- Test hot and cold separately at several fixtures — the pattern narrows the cause quickly.
- Unscrew and rinse the aerator on a weak faucet.
- Confirm the main shutoff and meter valve are fully open.
- Check the water bill and meter for signs of a hidden leak.
- If you have a whole-house filter, check when the cartridge was last changed.
Before the pro arrives
- • Note whether it is one fixture, one floor, hot only, or the whole house.
- • Know the home age and pipe material if you can.
- • Have a recent water bill handy if you suspect a leak.
- • Record when the drop started and whether it was gradual or sudden.
Questions to ask
- • What is my static pressure reading at the hose bib?
- • Is the pressure regulator functioning, and what is it set to?
- • Did you rule out a supply-side leak before replacing parts?
- • Are my supply pipes at the end of their service life?
- • What is the fix, and what happens if I wait?
Common questions
Why is my water pressure low all of a sudden?
A sudden drop across the whole house usually means a valve, the pressure regulator, or a supply-side problem such as a leak or municipal work. A gradual decline over months points more toward scale buildup or corroded pipes.
Low pressure at only one faucet — what is it?
Almost always the aerator or the fixture supply stop. Unscrew the aerator, rinse the screen, and reinstall it before calling anyone.
What should my home water pressure be?
Most homes run comfortably between 45 and 60 psi. Below about 40 psi showers feel weak; above 80 psi you risk damaging fixtures and appliances, and many codes require a regulator.
Can low water pressure mean a leak?
Yes. A slab or supply-line leak bleeds pressure continuously. If the meter turns with every fixture off, or the bill jumped without a usage change, treat it as a leak until a plumber proves otherwise.
Keep reading
Other common home problems
Start with the symptom and get likely causes, safety guidance, and a next step.
Fixly Guide provides educational guidance only. Nothing here is a professional diagnosis, an inspection, or a guarantee of contractor availability or pricing.