Standard Stair Rise And Tread Dimensions

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 rise and tread dimensions.

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. Handrail height to be placed a minimum 34 inches to 38 inches. Maximum 7 3 4 inch stair riser height. Standard stair tread dimensions.

Maximum 12 3 vertical height rise for a flight of stairs. A stairway in which there is a noticeable variation between the risers is a safety hazard. Minimum 10 inch stair tread depth with nosing or minimum 11 inches with no nosing. If the stairs have open risers the open space between the steps cannot be large enough to allow a 4 inch sphere to pass through.

Here is a drawing detailing our standard stair tread and riser dimensions. Handrail graspability to be either type i or ii with a minimum 1 1 2 inch clearance from a wall. Stair details refer to the standard requirements for each of the various components of a flight of stairs. All risers and all goings in the same flight of stairs shall be of uniform dimensions within a tolerance of 5 mm.