What I need to know is:
What dimension of lumber will suffice for a beam over a 4 foot span?
i.e. the longest the posts will be set apart is 4 feet and I don't want to use a 2x12 if a 2x6 will do.
What is the frost depth in the Washington, D.C. area?
ie. how deep do my footer posts have to be?
What do I set the bottom of the stair stringers on? They are very short, only three steps. Do I need to sink more holes and posts and bolt them in place or can I get away with a small concrete pad set flush with the ground for them to rest on? Can't they just ride on that?
Any help you can give would be most appreciated.