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Does rebar next to copper pipe cause electrolysis?

2004

Hi

I am having a custom home built in the high desert area. When I was at my new home I had a contract from down the hill come by and asked if he and his wife could look through the house. The house is 45% finished at this time. It is ready for a combo according to my contracter. The contracter from down the hill told me that I will have problems with my plumbing within 3 years because the contracter building my house left the rebar in the concert next to copper pipe. I was informed also that soft copper was used under the foundation. Some of the copper wire above ground is covered in plactic but is tied together with the rebar. In other places the rebar is touching the copper pipe. I was told that this causes electrolysis. Is this true, how long before this happens if so. What should I do?

Cindy Saari
homeowner - Victorville, California,

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In general: two different metals in contact in the presence of a conducting liquid yields electrolysis. That's what batteries are. Is it going to happen? Yes. How long? It starts immediately. How long before the pipe leaks? Who knows, it depends on a *lot* of things. Solution? Make *sure* that the copper pipe does not touch the steel. There are tapes made for wrapping pipe and electrical conduit that are buried. Perhaps they could be used decrease the problem. But remember that water pipes often move a little bit in use ("water hammer", etc), so wrapping with tape may be a long-term solution but not a 'forever' solution.

Good Luck!

Tom Gallant
- Long Beach, California, USA
2004

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The contractor down the hill is right. That is something that must be fixed before they pour. I don't know about the "soft Copper" but if the copper in the slab isn't covered and away from the rebar you will have LARGE problems.

Jeff Watson
- Pearland, Texas
2004