Copper/Galvanized Corrosion

I'm working on a bathroom remodel and have used copper plated stub-out brackets for the sink supply lines. I had to notch a stud to accommodate the new 1 1/2 inch drain line. I have used a Strong Tie strap to reinforce the stud (non load bearing) and to act as a nail plate. The strap is galvanized. Is this going to cause corrosion problems in the system?

Thanks for your help.

I don't think I would worry too much about the bracket. You could always place a couple wraps of electrical tape between the two surfaces.

Thanks for the response. I guess what I meant to ask was will the reaction between the dissimilar metals of the bracket and the strap cause corrosion to the copper pipes connected to the bracket or the fixtures attached to the pipes?

The strap is already in place and nailed off in every hole and the drywall is back up. I would prefer not to tear it apart, but will if it poses a threat.

Thanks again.

You may want to change it. The galvanic series for galvanized steel and copper indicate a difference of 0.85V. The maximum recommended is 0.5V in a controlled humidity environment. If the pipe sweats at all the corrosion will accelerate even more.

Tyson said:

Thanks for the response. I guess what I meant to ask was will the reaction between the dissimilar metals of the bracket and the strap cause corrosion to the copper pipes connected to the bracket or the fixtures attached to the pipes?

The strap is already in place and nailed off in every hole and the drywall is back up. I would prefer not to tear it apart, but will if it poses a threat.

Thanks again.

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when you have contact between two different materials like galvanized steel and copper it's likely that you'll have some galvanic corrosion. galvanic corrosion is a function of severeal factors and the difference in potential is just one; you'll have also to take into account the type of fluid, or atmospheric exposure and the ratio of the two areas in contact. if you have a large anode area, galvanized steel, and a small cathode area, copper, then the galvanic corrosion will be limited. what you can do is to isolate the two material of paint at least the galvanized steel.

galvanic corrosion documents

Vittorio

IF there is NO moisture at the point of contact there will be NO reaction. Water is the electrolyte that causes electrolysis to occur.