I'm designing a deck to build as a DIY'er this Spring, and would appreciate any input on my evolving design. The deck will be a single level, ~27" high, probably joist-on-beam using 2x10s for both (built-up beam), supported on top of a very short set of ~6" 4x4 posts on poured foundation piers.
A bird's eye view of the current (rough) plan:
As you can see, I'm planning a fairly large apron stair centered on a short 45° ear removed in the corner. Here are three successive views starting with stringers, adding treads, and then risers:
A few questions regarding this design:
1. Is this the simplest stringer layout? The double stringers each have 22.5° rise face cuts, but are mirror images of each other. All "straight" stringers are identical. So there are only 3 (or 2) versions.
2. Is this sufficient support for 5/4 or 2x decking material (probably cedar or PT)?
3. I'd attach the straight stringers to the rim joist with joist hangers. How should I attach the doubled stringers? Recall they are at a 45° corner in the rim joists, and are each at a 22.5° angle from the one to which they attach. In the ideal world there would exist a double joist 45° specialty hanger, but I have not seen one.
4. I'm trying to connect stair posts to rail posts in a continuous railing. Can the top post be notched on two sides, and bolted to the rim joist and stringer?
5. I'm thinking of attaching the stringers to a 2x6 PT board which will be buried in gravel. Will this be sufficient to keep them level and square to each other?
Thanks very much.
JDS