I want to replace a small flight of stairs to the basement due to sloping, squeaking and basically nothing holding it up.
The problem is there is no way to extend the total run due to an exterior door at the lower landing and another flight to the basement floor, so the stringers have very little to attach to. The rises and runs are already both near 8 inches so I really don't want to add a hanger board and that wouldn't fix the support for the bottom of the string. The only thing I can think of is to add three 2x6 and run them from the landing joist to blocking behind the top ledger joist. (see attached).
Yes, only three steps, total run is 24". My thought was to make the stringer fatter by sistering something to it.
Doubling the upper right joist would be problematic due to wires, pipes. The 2x10 at the bottom is attached to posts about 3 feet apart with three 3/8 lags each. I was just going to attach the stringer with angle brackets at the bottom and lags at the top through the blocking. The 2x6s would only be 54" total length.