How to Support a Concrete Porch

[eaglefan45]

Any help on how to support a concrete porch? I'm designing a porch - dimensions 16 x 21 and will be pouring the porch surface, either with stamped cement or cement base and then flagstone surface. Based on landscape I must pour footers, construct block walls, then pour the cement onto steel decking. Not sure how to span the decking for supporting the surface. Appreciate any guidance. thanks

[lefty]

I'm not sure what you are asking.

A 16' X 21' slab can be laid right on grade. If there's a slope involved, you might need a stem wall to compensate for that, backfill within the stem wall, then our the slab. "Steel deck"?? I'm lost -- what's that all about???

[Mike Swearingen]

Mike,
I think that eaglefan45 is planning a raised porch deck poured onto galvanized steel roofing and wants to know how to support the steel roofing under the poured concrete to keep it stable to prevent future cracking.
I think that a pressure-treated wood frame and joists under the galvanized would do it. I've never done it, but I've seen it done.
Just don't know what to advise on the framing to support the weight. I suppose that a standard p-t deck base might support it well enough. Once the raised slab hardens, it should be stable as long as it can't move.
What do you think?
Mike