This one needs a licensed pro
Likely cause: clogged or corroded pipes
Pressure that fades over years with the mains open often means old pipes narrowing inside, or a hidden leak. That is a plumber's call.
Why this happens
Mr. Rooter lists clogged or corroded pipes and leaks among the causes of low water pressure, and says whole-house low pressure that keeps returning means calling a plumber. Mr. Rooter's quick check is to scratch a pipe with a nickel: copper looks penny-colored and galvanized steel looks steel-gray.
What to do right now
- Find a section of exposed supply pipe near the main or water heater and scratch it with a coin to see the material.
- Check for signs of a leak: damp spots, a running sound with everything off, or a meter that moves when no water is in use.
- Note which fixtures are weakest and whether it is worse upstairs.
- Call a licensed plumber.
What to tell the plumber
- Whole-house pressure has faded slowly over time with the mains fully open.
- The pipe material from your scratch test.
- Any signs of a leak, and which fixtures are weakest.
- The age of the home.
Build the full list: what to tell the plumber.
Start this troubleshooter over
References (every fact above comes from one of these pages)
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