Standard stair tread dimensions.
What is a standard stair tread size.
For recommendations on rise run combos see the tip below.
The stair tread depth shall be measured horizontally between the vertical planes of the foremost projection of adjacent treads and at right angle to the tread s leading edge.
A prime example is the standard stair width.
But we recommend that stairs should be at least 48 inches wide so they don t feel cramped.
These dimensions may be useful when laying out a staircase or if you have general questions about the size and shape of a traditional tread or a retro tread.
Stair tread depths shall be 11 inches 279 mm minimum.
Because they only sit on the top of the stair the length of the tread is limited to the size of the average step.
Harvard university lists typical tread sizes between 8 and 11 1 2 inches.
Regulated by building codes stair details specify the sizes of risers and treads stair widths the placement of handrails and guardrails and construction methods for fabricating stairs.
The stair treads should be at least 36 inches wide.
Unit run is carefully considered based on both safety and cost.
The minimum tread size is commonly stated as 9 inches for residential construction.
Most stair treads are not made to wrap around the lip of the stair.
Staircase code states that stairs must be 3 feet wide or wider.
Here is a drawing detailing our standard stair tread and riser dimensions.
At the same time staircase code measurements do allow for some flexibility since most measurements are accompanied by minimums or maximums.
Stair details refer to the standard requirements for each of the various components of a flight of stairs.
Nine inch stair treads are the most common lengths.
A tread thickness b bull nose height 1 1 16 c bull nose depth 1 d internal length 36 42 or 48 e return length 13 f tread width 11 g return extension 1 h return width 1 i external length 38 5 44 5 or 50 5.
Increasing the length of the run by the smallest unit of measurement increases cost and the length of a staircase.
The maximum allowable stair rise is 7 3 4 inches and the minimum stair rise is 4 inches.