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Powder coat VS 2- Coat Polyurethane finish

 

I have been given the task of finding out which of the two coating processes are more advantageous to the owner of a 5-story concrete parking garage at an airport. This would encompasses mostly hand rails that are exposed to weather.. The concerns would be mostly longevity, ease of maintenance and repair. I do not currently have a spec for powder coating. Here is the spec for the 2-coat polyurethane system. Primer: Two component polyamide epoxy, zinc rich metal primer applied at spreading rate recommended by the manufacture to achieve a total dry film thickness of not less than 4.0 mils. to 5.0 mils.DFT. Product shall have minimum of 64% volume solids and 85% by weight zinc. First and second coats: Full gloss exterior, high solids polyurethane applied at spreading rate recommended by the manufacture to achieve a total dry film thickness of not less than 3.0 mils. Product shall have minimum 65% volume solids. I had hoped that there would some testing from other than the manufactures.

Eric P [last name deleted for privacy by Editor]
- Spokane, Washington, USA

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Hello Eric,

Powder-coating will give you better durability compared to the polyurethane. The hand rails will need to be dismantled and brought to a powder-coater, the polyurethane could possibly be applied on the job-site (check with the manufacturer, the hand rails might be out of service for a few days while the coating cures).

Hope that helps,

Jake Koch
G. J. Nikolas &Co.,Inc.

Bellwood, Illinois