Hello. I have a stair stringer that split at the bottom stair on both stringers. Now I'm not too sure on how to measure for new stringers. The old stringer is being supported by two bricks at the bottom step. I guess when they built the stairs they miscalculated. The stairs lead into my basement from the front door entrance. I measured the height from the basement floor to the top of the front entrance floor. It is 49 1/2". I came up with 7" rise. I think I'm right? Can anyone tell me the right measurements for my rise and run? I'm using a 2x10 stringer and the treads measure 9" x 42 1/2" wide.

So you know the total rise. What's the total run and how many treads.
Note that the minimum tread width is 9" plus 1" nosing. Meaning minimum tread width is 10".

I think you are going to need 2x12 stringers.

There are currently 5 treads right now. So go with 2x12 stringers, 7" risers, and 10" run?

Try this calculator and you will need at least 3 stringers due to your width.

What is total run

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