Using the Stair Calculator

Use the stair calculator to calculate the slope of stairs. The calculator applies a common, rule-of-thumb formula, such as a formula specified in the Architectural Graphic Standards. Before using the stair calculator, specify the values for the minimum tread depth and maximum riser height.

1. In the drawing area, select the stairs.
2. On the Properties palette, click Edit Type.
3. In the Type Properties dialog, for Calculation Rules, click Edit.
4. In the Stair Calculator dialog, select Use Stair Calculator for slope calculation.
5. Under Calculation Rule for target slope, enter a value to multiply by Rise.
6. Enter a value to multiply by tread Depth.
7. Enter a Maximum Result and a Minimum Result for the stair calculator.
   Note: The stair calculator uses the tread depth you specified in the instance properties of the stairs. If the value you specified causes the calculator to produce values that are outside the range of the acceptable results, a warning is displayed.
8. Click OK.

   The stair calculator computes the tread depth for new stairs only; existing stairs are not affected.