Total Staircase Run
The total staircase
run is often referred to as the stair run or the distance required to
install the stairway, horizontally (from side to side or from left to
In my book (Simplified Stair Building) I use a lot of pictures, because pictures really are worth a thousand words. In other words, pictures usually make things a little easier and easy is good, especially when you're doing something that you haven't ever done before.
The stair run is going to be the horizontal distance measured from the first step at the bottom of the stairs, to the last step at the top of the stairs. This measurement can usually be taken on the ground and laid out accordingly.
This is the measurement that you will need to divide and create equal stair treads.