just bought a house where we've got an existing concrete slab porch that is 12" above the adjoining sidewalk and it does not have a step. We want to add in a large 6" tall x 3' wide x 11' long slab that will act both as the new step to the porch and also give some area for planters on each end.
With 6" above grade and the size of this thing, how deep below grade should our concrete go? We were thinking 4" and then 4" of gravel beneath that.
For this size slab, should we use 1/2" rebar or would 4" welded wire mesh still be ok?
Since this will be right next to the existing poured porch, should we join the two together with 1/2" rebar or keep slab & porch separate with a small gap (1/4")?