I'm running a new electrical run along the rafters in my house and I had a few questions I wanted to check on before I started. Are there any general rules and or best practices when running flexible aluminum MC around and near copper water pipes and any plumbing for that matter? Are there any good standoffs to keep the aluminum from touching the copper water lines and is there any concern for galvanic corrosion or something of the sorts? Thank you for any help.

Royce M

Hi, I work on commercial refrigeration in which we run flex all over the place in proximity to copper piping. As far as residential is concerned I couldn't comment on those details but I do know that general code will allow it, there's just a couple of things to think about when doing it though. I wouldn't run the flex in a manner where it comes in contact with the pipe but if its unavoidable you can wrap either, the pipe in insulation, or the flex. However, if it is HOT water piping you'll want to make sure that whatever you end up insulating with is resistant to high temps.

In general, there is no requirement to keep aluminum cable away from copper piping. We keep our wiring away from other systems as standard practice, however, for example, in partitions, cables often run next to or cross other systems, without any apparent problems.

Thank you