zig
0

Notifications

  • You're all caught up!

What Is the Standard Size of a Stair Step?

by
author image Don Patton
Don Patton began writing after retiring from an engineering career in 2006. He holds a Bachelor of Science in electrical engineering from the University of California at Berkeley and continued with graduate study in software engineering.
What Is the Standard Size of a Stair Step?
Stay alert when walking up and down stairs. Photo Credit Jupiterimages/Brand X Pictures/Getty Images

Stairs can be dangerous. Falls from stairs kill thousands of people each year in the United States and injure millions more. While there are no universally accepted standards for the design of stair steps, there are general guidelines intended to reduce the risk of accidents. Local building and fire codes contain rules to ensure stair safety, and some have adopted the provisions of the national building code established by the Building Officials and Code Administration (BOCA).

Riser height

The most significant safety feature of steps is that they be uniform in height. A sudden departure from an even gradation can cause you to misstep, so building codes generally require tight tolerances on the variation in riser height. The BOCA code also specifies a maximum height for each step of eight and one-quarter inches. Some codes restrict this height even further, limiting the rise to only seven inches.

Pitch

The pitch of a staircase is how steep it is, specifically the angle from the same point on one step to the next one. Those who study stairs believe a pitch of between 20 and 50 degrees is safe, and being within the range of 30 to 35 degrees is best. Another rule of thumb for riser and tread design is that the sum of the two dimensions be between 17 and 17 and one-half inches. If a riser is seven inches high the tread depth should be no more than 10 and one-half inches deep. These dimensions also result in a safe pitch angle of 34 degrees.

Tread Depth

The BOCA guidelines also specify a minimum tread depth of nine inches and allow for a one inch protrusion, which is known as nosing. Some safety groups instead suggest a minimum tread of 11 inches. As with riser height, it is important that the tread depth be as consistent as possible to avoid causing you to stumble.

Width

Local codes typically specify stair step width limits. Usually the minimum for residences is from two feet eight inches to three feet six inches. There are no maximum widths, but stairs wider than 44 inches may require hand rails.

Landings

Local codes may require landings for staircases that rise more than a total of 12 feet. If so, the length of the landing should be equal to or greater than the width of the steps.

LiveStrong Calorie Tracker
THE LIVESTRONG.COM MyPlate Nutrition, Workouts & Tips
GOAL
  • Gain 2 pounds per week
  • Gain 1.5 pounds per week
  • Gain 1 pound per week
  • Gain 0.5 pound per week
  • Maintain my current weight
  • Lose 0.5 pound per week
  • Lose 1 pound per week
  • Lose 1.5 pounds per week
  • Lose 2 pounds per week
GENDER
  • Female
  • Male
lbs.
ft. in.

YOU MIGHT ALSO LIKE

CURRENTLY TRENDING

Demand Media

Our Privacy Policy has been updated. Please take a moment and read it here.