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Attaching a copper trellis to a galvanized structure+++
We are building a copper trellis on an existing greenhouse frame. We will be attaching copper tubing to the existing galvanized pipe of the structure, using copper straps. My question is this:Will the intersections of the copper and galvanized pipe corrode from rain,dew, moisture in the air? Also, if we use steel sheet metal screws or zinc coated screws to attach the copper straps, will the screws corrode where they touch the copper? If so, is there a better fastener to use?
Thank you for your help,Leslie L. Rose
designer - Walworth, Wisconsin, U.S.A.
The zinc of the galvanized surface is far more active than copper, so it's corrosion will be accelerated. It's generally a bad idea to make a connection like this; you really should insulate the connection in one way or another. Brass or stainless screws would be better.
Ted Mooney, P.E. RET
Pine Beach, New Jersey