Galvanised Pipes in Older Homes: When to Re-pipe

Published 2026-06-01 · Cambridge Plumbers

What goes wrong with galvanised pipe

Galvanised steel pipe was standard in NZ homes for decades, but the internal zinc coating eventually wears away and the steel underneath rusts and scales up. The pipe slowly closes over from the inside — which is why an older home’s water pressure quietly gets worse and worse over the years.

Signs your home needs a re-pipe

• Weak water pressure, especially upstairs or when two taps run at once
• Discoloured or rusty water, particularly first thing in the morning
• Pinhole leaks appearing in walls, under the house or at fittings
• Visible corrosion on exposed pipes in the subfloor or roof space

What a re-pipe involves

We replace the old galvanised lines with modern PEX or copper, usually staged to keep the house liveable. It’s often done alongside a mains-pressure hot water upgrade, because there’s no point pushing good pressure through pipes that are choked. The result is strong, clean, reliable water through the whole house.

Is it worth it?

For a character Cambridge home you plan to keep, almost always — failing pipes only get worse, and a burst inside a wall does expensive damage. We can inspect your pipework, tell you honestly how much life is left in it, and stage a re-pipe to suit your budget.

How we can help

• Mains-pressure hot water upgrades
• Renovation & re-pipe plumbing