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.
Standard stair rise and tread dimensions.
Maximum 12 3 vertical height rise for a flight of stairs.
Minimum 10 inch stair tread depth with nosing or minimum 11 inches with no nosing.
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.
Application this section covers all stairways including standard spiral ship and alternating tread type stairs except for articulated stairs stairs that change pitch due to change in height at the point of attachment such as those serving floating roof tanks stairs on scaffolds stairs designed into machines or equipment and stairs on self propelled motorized equipment.
Standard stair tread dimensions.
Handrail height to be placed a minimum 34 inches to 38 inches.
Maximum 7 3 4 inch stair riser height.
The greatest riser height within a flight of stairs cannot exceed the smallest by more than 3 8 inch.
Here is a drawing detailing our standard stair tread and riser dimensions.
The tread depth td is to be 185mm and it should not be more than 30mm shorter than the going g.
A stairway in which there is a noticeable variation between the risers is a safety hazard.
All risers and all goings in the same flight of stairs shall be of uniform dimensions within a tolerance of 5 mm.