Another source is dock and pier supplies. I walked on a really cool pier near Monterey that had the decking made of grate-like composite material. It was strong and might be a possible source. I think the composite decking was secured to either wood or some sort of metal. It looked like this:
Patriot Docks Gray Poly 4x4' Deck Section | Wholesale Marine
The Patriot Docks Gray Poly 4' x 4' Deck Section includes 2 aluminum stringers and comes with the assembly hardware needed to install this deck section onto your Patriot Dock. Get yours today at Wholesale Marine for free shipping.
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