OT - Options for waterproof and fireproof deck?

[jackaustin]

I'm about to replace two small deck surfaces over living areas, and perhaps convert another large deck to waterproof construction to allow storage underneath.

What's common here (and the one that needs replacing) is fabric layers embedded in acrylic latex, followed by a topcoat. Relatively easy to do, moderate cost, but only seems to last 15-20 years. Less if there are any roof penetrations for rails or any movement of the ply underneath.

Are there better alternatives to waterproof deck Utah?

For the large deck, I see interlocking vinyl deck planks. But, they're not fireproof. Cement-based coatings (plywood, galvanized lath, then elastic cement) seem a possibility (like "Desert Crete"), but what little information I have suggests they cost 2x and don't last any longer. I suppose an elastomeric roof with some sort of protective surface is another option.

Does anyone have a handle on this -- or experience with something that has performed well?

 

[BridgeSmith]

The (highway) Bridge Engineering forum is probably not the best place to post this question. We deal with primarily concrete and steel structures that don't require fireproofing, and not the kind waterproofing that would be used for your application.

Rod Smith, P.E., The artist formerly known as HotRod10