How To Figure And Calculate Stair Stringers

You can use this page to figure and calculate stair stringers, but it would be difficult to cover every type of stair stringer, so keep that in mind. The information on this page will provide you with the basics and will be applicable to most stairway installations.

The first thing you will need to do, is measure the total run or horizontal distance of the stairway.

Next you will need to measure the total distance between floors. Then use this information with the two links listed below, to figure out and calculate the individual stair tread and riser measurements.

How To Figure And Calculate Stair Treads
How To Figure And Calculate Stair Risers

In the next step I would like you to rotate the stringer around in your mind. I know this might sound kind of goofy, but it will make a big difference when laying out all of the measurements on your stair stringer.

This is the position you will be working with, while laying out the stair stringer. This is probably the biggest problem a beginner stair builder will have and with only a couple of pictures, you should have a better understanding of what you're doing, when you're doing it.

I placed the stair stringer for our example on top of a 2 x 12. If you can imagine your stair stringer already cut, laying on top of a yellow 2 x 12, you should get a better idea, why I rotated it.

This seems to be one of the most difficult parts of laying out the staircase stringer. It's hard for most people to imagine in their mind, turning the stair stringer around and then laying it out, upside down.

Next - How To Layout And Mark Stair Stringer

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