How many treads are required for a set of stairs with an 8-foot rise?

To determine the number of treads required for a set of stairs with an 8-foot rise, it's essential to understand the relationship between the rise and the run of the stairs. Stairs are typically constructed with a formula that balances the rise (vertical height) and the run (horizontal distance).

In residential construction, a common rule of thumb is to have a rise of no more than 7 inches per step. An 8-foot rise translates to 96 inches. If you divide the total rise by the maximum recommended rise per step, you can calculate the number of steps needed.

Using the 7-inch rise guideline, dividing 96 inches by 7 inches gives approximately 13.71 steps. Since you cannot have a fraction of a step, you'd round up to ensure the entire rise is covered appropriately, leading to a necessity of 14 steps. However, the 1 foot of flat space at the top of the stairs counts as a tread as well.

Considering this, if 13 risers are used, there are typically 13 treads (one tread is at the top). Thus, the correct total number of treads is indeed 13, aligning with the answer provided.