What galvanized pipe is
Galvanized pipe is steel coated with zinc to slow rust. It was a standard material for house water lines for much of the twentieth century, and plenty of Fullerton homes from the postwar building boom were plumbed with it. The zinc coating wears away over decades, and once it does, the steel underneath begins to rust.
The rust builds up inside the pipe rather than outside, so the pipe can look fine from the crawlspace while its opening shrinks. Hard water adds mineral deposits to the mix. The result is the slow loss of pressure and the brown morning water that many owners of older homes learn to live with until a leak forces the issue.
How to check whether you have it
You can do this without tools in a few minutes.
- Look at the water heater.Check the pipes coming out of the top of the heater and where they enter the wall. Gray threaded pipe is a strong hint.
- Check under sinks.Look behind the shutoff valves where the pipe comes out of the wall. A gray stub with threads is often galvanized.
- Find the main line.Look where the water line enters the house, often near a front hose bib. Note the color and whether joints are threaded.
- Use a magnet.A magnet sticks to galvanized steel. It will not stick to copper or plastic.
- Scratch lightly.A light scratch with a key shows silver-gray on galvanized and reddish metal on copper.
Galvanized at a glance
- Color
- Dull gray, sometimes painted
- Joints
- Threaded, with fittings screwed together
- Magnet
- Sticks
- Main failure
- Internal rust that narrows the pipe
- Typical symptoms
- Low pressure, rusty water, leaks at threads
Common choices for a galvanized house
- IfGalvanized is throughout the houseA whole-house repipe in copper or PEX is the usual recommendation, since the remaining pipe has the same age and wear.
- IfOnly a few galvanized sections remain after past repairsReplacing those sections may be enough. Ask for a walkthrough of exactly where they are.
- IfThe main line from the meter is galvanizedAsk whether the main will be replaced too. New interior pipe fed by a rusted main still gets rust and low pressure.
Ask about a galvanized replacement
- Is any galvanized pipe staying in the house after this job? Where?
- Will the line from the meter to the house be replaced or only the interior lines?
- Will old pipe be removed or abandoned in the walls?
- Are new shutoff valves included at every fixture?
Common questions
Can galvanized pipe be cleaned out?
The rust is part of the pipe wall, not a removable clog. Flushing may clear loose sediment briefly, but it does not restore the pipe.
Is rusty water from galvanized pipe dangerous?
Discolored water should be investigated. Run cold water until it clears and consider testing. Questions about the city's supply can go to Fullerton's water utility.
Does old galvanized have to be removed from the walls?
Often it is disconnected and left in place to avoid extra demolition. Ask the plumber which approach they plan.
General information for Fullerton, not a quote or professional advice. In an emergency, call 911.