Why have my copper pipes gone green?
Copper pipes that have turned green, or have green or blue crusty build-up on them, are showing corrosion. Sometimes that's just a harmless surface patina, like an old copper roof. Sometimes it's the tell-tale sign of a slow leak at a joint that's been weeping for months. Here's how to tell which one you're looking at, and when to get it checked.
Harmless or a problem?
Even, dull green film
A thin, even green layer over a whole length of pipe, especially outdoors or near the coast, is usually surface patina from moisture and salt air. Generally harmless.
Crusty green at a joint
A lumpy green or blue crust concentrated at a fitting or solder joint usually means water is slowly seeping out and leaving minerals behind. That's a leak.
Green with white deposits
Green and white build-up together, sometimes with a damp patch, also points to a slow leak.
Green stains in basins or showers
Blue-green staining under taps can mean copper is being dissolved from the inside, which is worth checking.
Quick checks
- Wipe the area dry and check it again later. If it's damp, it's leaking.
- Do the water meter test: everything off, note the reading, check again after an hour. See our hidden water leak guide.
- Look for green build-up at joints under sinks, at the hot water system and under the house.
How we fix it
We check the affected joints and pipe, pressure test the system, and repair any leaking fittings or sections. Where copper has thinned or pitted badly, replacing that section is the lasting fix. You get a fixed price before any work starts. See leak detection.
In southern Eastern Suburbs homes
Salt air in Maroubra, Malabar and Little Bay turns exposed copper green quickly, and that's usually cosmetic. Under older homes in Matraville and Botany, crusty green joints are often slow leaks that have been dripping onto the soil for years.
Why locals call us
- Local to Matraville and the southern Eastern Suburbs
- Free on-site quotes, with a fixed price before any work starts
- Lifetime labour warranty on our workmanship
- 100+ five-star Google reviews
- Licensed plumbers and gasfitters (Lic. 398171C)
Common questions
Is green on copper pipes a problem?
An even film is usually harmless patina. Crusty green build-up at a joint usually means a slow leak.
Why are my copper pipe joints green?
Water slowly seeping from the joint leaves copper corrosion and minerals behind. The joint needs repairing.
Can I clean the green off copper pipes?
You can clean surface patina, but if the green is at a joint, check for a leak first.
Why is there blue-green staining in my basin?
It can mean copper is being dissolved from the pipes. It's worth having the water and pipes checked.
Related help: leak detection, hidden water leak guide, pipe types, galvanised pipes guide and I can hear water running. Local pages: Maroubra, Malabar, Matraville and Botany.