Plumbing in 1970s Mission Viejo Homes: What Was Installed, How It Has Aged and What to Plan For Now
Thousands of Mission Viejo homes were built in the 1970s and still run on their original water lines. What builders used then, the problems that show up after 50…
A large share of Mission Viejo's homes went up during the 1970s, when the city was growing fast around the lake and the hills. Many of those houses still have the water lines the builder installed. After roughly 50 years, it helps to know what is behind your walls and what tends to go wrong with it.
What builders installed in the 1970s
Most homes from this era in south Orange County were plumbed with copper supply lines, typically thin-wall Type M copper inside the house. Joints were soldered, and before the late 1980s that solder often contained lead. Many homes were built on slabs, and some lines were run under the concrete. Shutoffs were often gate valves with round handles.
How it has aged
- Pinhole leaks in copper, especially on hot lines and near elbows
- Slab leaks where copper under the floor has worn or rubbed against concrete
- Stuck or leaking valves at the main, the water heater and under sinks
- Lower pressure as scale builds up inside small lines
- Past patch repairs that mix copper with other materials
What to check now
- Look at exposed copper in the garage, under sinks and at the water heater for green crust or white mineral buildup.
- Try your main shutoff and fixture valves to see if they close.
- Note how many leaks the house has had and where.
- Check your water pressure at an outside spigot.
Planning instead of reacting
The most expensive way to deal with 50-year-old pipe is one emergency at a time, with drywall, flooring and insurance claims each time. Planning a repipe on your schedule lets you choose the timing, combine it with a kitchen or bath remodel, and route new lines overhead rather than under the slab.
Mission Viejo homes from this era
Mission Viejo was built mostly from the late 1960s through the 1980s. Many 1970s homes are in the neighborhoods around Lake Mission Viejo, the older Deane-built tracts and the Casta del Sol 55+ community, along with areas near Marguerite Parkway and La Paz Road. Water is supplied by Santa Margarita Water District or Moulton Niguel Water District. HOAs in many neighborhoods set rules for contractor hours and parking.
How a repipe works here
We replace the old copper with PEX-A routed through the attic and walls, add new quarter-turn shutoffs, and leave the old under-slab lines out of service. The work is permitted and inspected through the City of Mission Viejo, and most families stay home during the job.
Related reading
Learn how to check for a water leak or read about hard water buildup in pipes. Neighbors can visit Laguna Hills, Rancho Santa Margarita and Ladera Ranch, or see every city we serve at repipeinc.com.
Living in a 1970s home?
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Repipe OC, 23821 Hillhurst Drive, Laguna Niguel, CA 92677, (949) 524-2362, CSLB #1087885 C-36.
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Written by Repipe OC · CSLB #1087885 C-36 · 23821 Hillhurst Drive, Laguna Niguel, CA 92677 · (949) 524-2362