If you are buying a home built before 1970, there is a real chance the water supply pipes are galvanized steel. Here is what that means, why inspectors flag it, and what it means for you as a buyer.
What Is Galvanized Steel Pipe?
Galvanized steel pipe is steel pipe coated with a layer of zinc to resist corrosion. It was the standard material for residential water supply lines in the United States from the early 1900s through the 1960s and into the early 1970s before copper became widely preferred.
The zinc coating was supposed to protect the steel from rusting. In practice, the zinc coating wears away over decades, and then the steel underneath begins to corrode. The corrosion builds up on the inside of the pipe, which restricts water flow, reduces pressure, and eventually leads to leaks and pipe failure.
How Long Does Galvanized Pipe Last?
Galvanized pipe has an average lifespan of 40 to 70 years, though this varies widely based on water chemistry and installation quality. A home built in 1950 with original galvanized pipes is now over 70 years old, which means those pipes are at or beyond typical lifespan.
What Are the Signs of Failing Galvanized Pipe?
Low water pressure throughout the house, especially when multiple fixtures are running at the same time, is the most common symptom. Discolored water, especially at first turn-on after the water sits unused, is another sign. Rust-colored staining at fixtures suggests the pipes are corroding. Visible surface rust on exposed pipe sections is concerning.
What Does Galvanized Pipe Replacement Cost?
Partial repiping of the most affected sections runs $2,000 to $5,000. A full repipe of a typical single-family home replacing all supply lines with copper or PEX runs $5,000 to $15,000 depending on home size and accessibility. Portland homes built on a raised foundation with a crawlspace are generally easier and less expensive to repipe than slab homes, because most of the piping is accessible from below.
Should This Affect Your Buying Decision?
Galvanized plumbing is not a reason to automatically walk away from a home. It is a reason to factor a repiping budget into your purchase planning or to negotiate a price reduction that accounts for the work needed. A home with original galvanized pipes that has been well maintained and still has reasonable pressure is a different situation from one where the pipes are actively failing.
Your inspector will document the pipe material observed, check water pressure, and note any visible signs of corrosion or leaks. Schedule your inspection here.