How to Figure Stair Stringers
Want to learn how to figure stair stringers? Stringers are the backbone of the stairs, so it is important to be precise when calculating measurements for them. Follow the instructions below to ensure you will have a solid foundation to your new remodeling project. It has been said that performing this project is like solving a tough geometry problem.
Step 1 – Take Measurements
Figure out the heights of the finished floor, deck or sidewalk surface. This will determine the rise of the stairs.
Step 2 – Determine Stair Tread Thickness
Determine how thick the stair tread will be. This typically is one inch, or the thickness of five deck boards.
Step 3 – Lay Out Stair Treads
Lay out heights of the upper surfaces of the stair treads. This is the surface that will be walked on, and also the surface the building inspector measures from. This can be done by subtracting the riser height from the finished deck surface, giving us a location for the top of the upper tread. Next, subtract the riser height from the top surface line to figure the top surface of the second tread, etc.
Step 4 – Subtract Stair Tread Thickness
Subtract thickness of the treads to figure out the horizontal lines that will have to be marked on the stringers.
Tips
- Using a computer-aided drafting program is helpful when determing the measurements, and will help to ensure accuracy.
Warnings
- Make sure your measurements are accurate. If one number is calculated wrong, it can throw off the entire project.
Items Needed
- Computer and CAD program (optional)
- Calculator
- Ruler or measuring tape
- Stair stringers