Whole-house repiping in Costa Mesa

The City's April 2021 Housing Element, using census survey data from 2014 to 2018, breaks down when Costa Mesa's homes were built. Almost one in five went up in the 1950s. About a quarter went up in the 1960s and another quarter in the 1970s. Roughly 73% of the housing stock predates 1980. That is the post-war boom that followed the Santa Ana Army Air Base years, when many people who trained here came back to stay.

The third column is what we see in the field, not a census figure. Every house is different, and many older homes have been partly repiped already. The only way to know what is in your walls is to look at exposed pipe at the water heater, under sinks, at the hose bibs and in the attic.

Galvanized steel in 1950s homes

Galvanized steel is iron pipe coated with zinc. Moen's guide to galvanized plumbing says that if a home was built before 1960, chances are its plumbing is galvanized steel or iron, and that problems start to show up after 30 or 40 years as the zinc layer wears away. Rust then builds inside the pipe, pressure drops, and the water can turn brown. In Costa Mesa, that describes many homes from the 1950s, since about 19% of the city's homes were built in that decade.

A quick test from the same Moen guide: scratch an exposed section of pipe with a coin or screwdriver. If it looks metallic gray and a magnet sticks, it is likely galvanized steel. Copper scratches to a bright penny color. PEX is plastic tubing, usually red, blue or white.

Copper in 1960s and 1970s slab homes

Many of Costa Mesa's 1960s and 1970s homes, which together make up about half the city's housing, sit on concrete slabs. Their copper supply lines often run under or through the slab. When that copper develops pinhole leaks after decades of service, the leaks show up as warm floors, damp carpet or a running water meter. A repipe in a slab home usually abandons the old under-slab lines and runs new pipe through the attic and walls, so the slab stays closed.

The 18 inch rule at the water heater

The City of Costa Mesa's water heater installation standard, on its form dated September 2024, says no PEX or similar plastic tubing may be installed within the first 18 inches of the water heater. In practice, a PEX repipe in Costa Mesa uses metal pipe (usually copper) for the hot and cold connections at the heater, then transitions to PEX beyond that point. If an inspector sees plastic tubing right at the heater, expect a correction. The same standard covers seismic straps, the relief valve drain and where a heater may be located. Our water heater repair and replacement page covers that standard in detail.

How we help you choose

• Budget first. PEX usually lowers material and labor cost, especially in larger homes with long runs.
• Walls and ceilings. If you want the least drywall opened, PEX tends to win because it can be fished through.
• Preference and resale. Some owners simply want copper. That is a valid choice and we price it.
• Mixed systems. Copper at the heater and exposed areas, PEX in the walls, is common and meets the City rule.

We give both prices in writing when you ask, so the choice is yours, not ours.

These are published estimates, not our prices. The things that move a Costa Mesa repipe within that range are:

• Number of bathrooms, kitchens and laundry hookups.
• PEX or copper, and how much copper is used at the heater and in exposed areas.
• Slab or raised floor, and how easy the attic is to work in.
• Whether drywall patching and paint are included.
• Permit and inspection costs, set by the City.
• Whether gas piping or a water heater is being replaced at the same time.

For an exact quote on your home, call (657) 669-4766. The written price comes before any work begins. Our plumbing costs guide collects other published ranges for common Costa Mesa jobs.

When a single slab leak is the trigger, compare the slab repair range above with the repipe range. If the home has had more than one slab leak, a reroute or repipe often makes more sense than paying for repeated repairs to the same aging pipe.