PlumbingUpdated October 23, 2026 · 7 min
Low Water Pressure in the House: Causes and Costs
Low pressure can come from a clogged aerator, partly closed valve, failed pressure regulator, supply interruption, or hidden leak. A sudden whole-house drop deserves prompt attention.
URGENCY
Prompt if pressure dropped suddenly
TYPICAL COST
$120–$1,500
Safe checks you can do now
- 1Compare hot and cold flow at several faucets and showers.
- 2Clean a removable faucet aerator after closing the faucet.
- 3Confirm the main shutoff is fully open without forcing a stuck valve.
- 4Check the water meter for movement while all fixtures and appliances are off.
Common causes
Fixture buildup
Mineral deposits can restrict one aerator or showerhead.
Pressure-regulator fault
A failing regulator can lower or fluctuate pressure throughout the home.
Supply leak or restriction
A damaged service line or corroded piping can reduce whole-house flow.
Call a professional when
- Pressure dropped suddenly throughout the house.
- The meter moves when every water-using device is off.
- You notice wet ground, wall stains, or unexplained water bills.
Related home repair guides
FIXAVUE provides general educational information, not a diagnosis or substitute for an on-site inspection. Call 911 for immediate danger.