How to Measure for a Curved Flight of Stairs

Most carpenters who build stairs can fit a curved stairway in 95 percent of the openings for a straight stairway. The cost to build stairs with a curve typically increases by 40 percent, but adds character and value to the home.

Instructions

1. Find the rise for your stairway. Measure the distance from the bottom floor to the top floor, which gives you the total rise.

2. Determine the height of the stair riser you plan to use when you build stairs. You may use a precut riser or build your own.

3. Divide the total rise by the riser height, which gives you the number of risers needed. Keep in mind you can't use a half step, so you need to round up or down and adjust the measurements.

4. Decide on the thickness of the stair tread material and layout the lines for the steps on paper. Subtract the riser height from the top of your surface height to place the first step. Then continue to subtract and layout steps until you reach the first floor.

5. Calculate the difference in measurement caused by the stair material's thickness.

6. Measure the run of the stairway to place stairs. You need to determine where to place the front step so the number of risers reaches the top floor. Include the nose of each stringer in the measurements.

7. Modify for the curve. To add a curve to the staircase, vary the length of the stair.

Tips & Warnings

• Use a CAD software program to provide specific measurements and quickly provide correct dimensions for building curved stairs.