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Is there a relatively easy way of stopping corrosion on a metal truss plate? I have wood roof trusses in a building on the beach and the salt air has begun corroding the metal plates within just a few years. I could attach plywood gussets over the plates but this would be quite extensive. I’d rather paint them with a zinc rich paint or something of that nature. Can anyone direct me to a manufacturer that could help me out with this?
In the long term, painting will not last. You are protecting the outer surface and even that will require up keep. REPLACE or fail.
For corrosion resistant finishes:
Hot dip galvanized (ASTM A 153) use hot-dip fastener. No galvanic cell between metals.
Stainless Steel (316) use stainless steel fastener. No galvanic cell between metals.
316 SST connector plates should also be used with new treated lumber, coastal zone, indoor swimming pool or corrosive chemical areas.