Slab Leaks and Pinhole Leaks in Orange County, CA

2/3/2014 (Permalink)

Small unseen leaks can cause big problems

Slab Leaks, the development of a pinhole leak in one of the copper lines below your concrete floor, are an increasing problem to property owners nationwide and our Orange County area in particular. Most homes built in our area since the late 60’s have a soft copper water system installed below the concrete slab on grade foundation. It is in this system that our homes are seeing frequent pinhole leak failures. We are acquainted with one commercial insurance adjuster in South Orange County who handles 6 to 7 slab leak claims per day for home owner associations.

According to a 2008 report published in Water Intelligence Online Pinhole leaks in copper water systems have been confirmed in all states and most major urban areas. Approximately 8.1 percent of homeowners nationally have experienced at least one pinhole leak and between 21-60 percent of homes in certain communities have developed pinhole leaks in their copper pipe water systems. We have found exceptionally high instances of leaks in newer homes in South Orange County including the communities of Laguna Niguel, Mission Viejo, Ladera Ranch, Rancho Santa Margarita and Anaheim Hills.

During our performance of hundreds of leak detection services for slab leaks and pinhole leaks here in Orange County we have seen type K hard and soft copper water lines, correctly installed, develop leaks within 3 years of installation. Two cases in particular come to mind:

• A 3 year old custom home in Shady Canyon, Irvine, had developed 3 active leaks below the slab. The installation of the soft copper type L lines was flawless with both hot and cold lines being fully jacketed with ½” closed cell insulation below grade. The failed lines had no contact with concrete or soil.
• A 6 year old townhouse in Ladera Ranch had developed a pinhole leak in the middle of a 10’ section of type L hard copper. This installation was also as close to perfect as could be with all piping isolated and supported on a hanger system with plastic inserts. When the leaking section was removed the internal pitting corrosion could be clearly seen.

Based on our observations of many pipe sections and repairs the pinhole leaks are a result of the water chemistry reacting with the copper and not external forces on the piping. We have observed internal pitting corrosion within most of the leaking lines we have opened for repair. Dr. Marc Edwards* of Virginia Tech has done extensive research into the copper pipe corrosion problem and his studies point to several factors that accelerate the incidence of internal pitting corrosion in our copper piping systems. Two key conditions he isolated are the reduction in NOM (natural organic minerals) as mandated under EPA clean water guidelines and the use of chloramine gas as a disinfectant.

As of this writing no one entity is accepting responsibility for the early demise of our household water systems. The water departments simply state that they are delivering water that meets the EPA guidelines and the Copper Counsel is virtually silent on the issue, they offer a 50 year warranty on copper piping but exclude corrosion. So we are on our own to repair or replace our failing copper pipe water systems.