While not new, since the concept was already described by Christopher Alexander in its architectural theories, it only gathered some traction in programming due to the publication of Design Patterns: Elements of Reusable Object-Oriented Software book in October 1994 by Erich Gamma, Richard Helm, Ralph Johnson and John Vlissides, known as the Gang of Four (GoF), that identifies and describes 23 classic software design patterns.
Use a calculator to calculate the stair riser length or the number of steps you'll need. Divide the height from the first floor to the top of the second floor by a predetermined height of your choice for the riser. The typical height of a riser is 6 or 7 inches (15 to 17.5 cm).
Stair stringer size. The stair stringer size can be chosen in the 7 inches for gaining the comfortable step of your stair. The, round the number of the calculation in the previous step for knowing how many steps that you will need in your staircase. Do not forget for writing the height of the steps which is needed. The next step in how to figure stair stringer length is deciding the tread depth or length of the stairs treads.