I am looking at putting in a step from my family room to the hallway which is perpendicular to the room. It is exactly 14 inches up from the family room floor to the hallway floor. I want to put in 2 metal stringers with a 1 inch thick step board. Problem is most of the stringers that I have seen have a vertical piece at the top of them that bolts to the wall, and that is fine as long as I can set them (the stringers) far enough apart to meet the door frame which is 36 inches. My concern is the step board will start to sag after a while, or will it? Am I okay with this distance between the stringers and not have the step sag? I am also thinking that I may bolt (or weld) a small "L" bracket in under the step between the stringers for support. What do you think?