Standard size of stairs

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When you are planning to build stairs, it is important to learn about the standard sizes of stairs. In fact, sizes of stairs are so important that builders are required to build them according to local building codes.

The standards are designed to ensure safety for all kinds of people, especially children and the elderly. Every part of a staircase needs to be designed accordingly, from the smallest parts to the overall structure.


Rise is the height of the entire staircase, from the lowest point to the highest point. Staircases vary in shape, but their rise is an important measurement for determining where landings are placed. Typically, a landing must be provided for every 12 feet (365.8cm) of rise, as per fire safety codes. Other than the code for landing placement, there is no requirement for rise length since every staircase is different from another.


Run refers to the length of the staircase, regardless of height. Run is used in conjunction with the rise and helps determine how many stairs there will be as well as the stair rise and stair run -- the rise and run of each individual step. Standardised codes with stair rise and stair run make it easier to design a staircase, regardless of run of the entire staircase. A staircase's run, however, is important if the staircase has one or more landings because there will be multiple run lengths. These will vary depending on the particular staircase that you are building.


Width refers to both the individual step as well as the entire staircase. The width of one stair, after all, will need to be consistent with the rest of the stairs. The stair's width usually varies depending on the type of building the staircase is in, but for a normal residence, the standard tends to be 3 feet, 6 inches (106.7cm). The minimum, in most places, is 2 feet 8 inches (81.3cm). If a staircase exceeds 44 inches (111.8cm), handrails are required for both sides.

Stair Rise and Run

Stair rise is the vertical measurement of the height between two stairs. Stair run is the horizontal measurement from the front to the back of a single stair. Standard code requires that a stair run should fall between 9 inches and 11 inches (22.9cm and 27.9cm) to allow people to safely ascend and descend stairs. Stair run is carefully considered based on both safety and cost. Increasing the length of the run by the smallest unit of measurement increases cost and the length of a staircase. Stair rise is normally about 7.5 inches (19.1cm).