Coating for structural steel?
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The elevated deck for my cabin is supported by HSS (hollow structural steel) components: mounting brackets bolted into the corners off the building, braces to support the main beams, and beams to support the joists and decking. The braces are 1/4″ x 4″ x 4″ and the beams are 1/4″ x 4″ x 8″. There are four beams approx. 22′ in length and four beams approx. 35′ in length.
I’m in zone 6b and I’m trying to figure out what the best coating is for these steel components so I don’t have a lot of rust stains on my metal siding. I’m not concerned about painting the steel to match the siding but just looking for the most cost-efficient method of coating the steel to reduce rust.
Any suggestions?
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Replies
David, the best coatings are not cheap, but they last a long time. There are epoxy and related coatings; this is a well regarded manufacturer: http://www.tnemec.com/. Or you could have the parts galvanized. For a good but less-durable finish, you could use a direct-to-metal enamel, such as this https://www.benjaminmoore.com/en-us/interior-exterior-paints-stains/product-catalog/ushpdtmae/ultra-spec-hp-dtm-acrylic-enamels. I would talk with a paint rep, as there are many options and situations.
Hopefully someone has already suggested to you that it's a good idea to fill hollow steel with closed cell foam, to avoid condensation and rust stains? For your big beams you might be ok with fully welded end caps, as long as they are airtight; they usually are not.
Thank you for the reply. After looking at costs, I'm leaning towards hauling the beams and braces into town and having them powder-coated.
If that's practically feasible, it's by far the best solution.