I've built a few 100% non-combustible decks, in fact we are working on one right now. The simplest ones are steel frame, aluminum decking, and steel railings. Nothing to burn there. The one we are currently doing is steel frame with paver stones and steel railings
The first one wouldn't work with the house. The second sounds interesting, but not exactly what we want. One really big consideration is access. I, or hired goons, am going to have to carry everything down a steep hill and then up to where it is used. No cranes, no lifts or hoists, no backing up to the site and unloading. Steel seems awfully heavy for my creaking old body. Am I wrong? Can you build a steel framed deck without machinery to lift the pieces into place?
Here's what I am planning:
Structure holding upper deck is a series of three arches on the front and one on each end. Inside of each arch is the diagonal which will be required to meet codes. Arches are stronger, but most people do not understand them, so I will have both. I was planning to frame them in PT and cover with stucco. They will go nicely with the house. The arches will enclose a lower deck which will be kind of a "loggia". At the end will be room for a pool, though we will never be able to afford one without winning the lottery.
Upper deck with be framed with 2x8 PT joists on 16" centers (just a five foot span plus one foot cantilever) decked with 3/4" PT plywood, sealed with copious amounts of Red Guard and covered with tile. Stucco siding on the house will be flashed onto the tile and the tile will be epoxy grouted. Underside of the deck will be covered with some sort of cement board - Hardi or something - and stuccoed, leaving no exposed wood.
Deck rails are to be cable railings because the only good think about this weird-assed house is the view. (The house is built like a whole bunch of boxes all piled haphazardly - I did not buy it, it came with the wife.)
I am very interested in suggestions for building the railings so they will meet code (200# lateral stress, etc.) and not leak when it rains. I welded up some for another deck but was not happy with how they turned out. I was told by a cable supplier that 1" steel posts would barely work. Turns out they barely don't work and will need to be reinforced. I will use larger steel on the next ones, so that should not be a problem. But attaching them was a PIB. I welded base plates onto them and bolted into the deck (it was L-shaped and supported on both ends, so meets the 200# rule.) I had to bed them carefully and fit tile around the bases. Not good. I am thinking of welding mounting plates to the sides of the posts and through-bolting to the rim joist of my deck. With enough bedding I think they can be waterproof. Do you think they will be strong enough if done that way?
Also, I used primer and paint on the first ones and had to re-work some rust spots after the first winter - no more after that, though. Is this normal for steel railings or is there a better way for an individual like me to do this? Is it practical to have them powder coated?
I might also pay my nephew to come over (from about 900 miles away) and weld up stainless steel railings. He is a pro welder. That would take care of the rust problem but might put me in the poor house!