If the stairway serves a floor with an occupant load of less than 50 the minimum clear width is reduced to 36.
Stair handrail width.
These calculations give you the required combined width of all exit stairs serving that floor.
For stair rail systems installed on or after january 17 2017 the top rail and handrail must be separate.
Maximum 7 3 4 inch stair riser height.
This allows taking into account stair stringer trim such as shown in our photographs.
For example the minimum hand clearance between the railing and the wall that it is mounted on is 1 1 2 inches.
Yet if the railing is pushed out too far there is the risk of violating another section of code that provides for 27 inches of walking width between the two railings of a double railing staircase.
On ramps the clear width between handrails shall be 36 inches 914 mm minimum.
However the minimum clear width between handrails is 44.
Maximum 12 3 vertical height rise for a flight of stairs.
Maximum stairway width permitting a handrail on just one side.
In general public spaces a minimum of 44 112 cm must be met providing ample space for one person and allowing the tight.
This space is shown with the green arrow in our photograph below.
Stairways less than 44 inches 1118 mm in width or stairways serving one individual dwelling unit in group r division 1 or 3 occupancy or a group r division 3 congregate residence may have one handrail.
The handrail itself should be easy to grip with a minimum diameter of 1 1 4.
Minimum 6 8 headroom height clearance for stairway.
For stairs serving a single user typically private residential a minimum of 36 91 cm is required.
The same height rules apply to stairs and the inspector measures the handrail height from nose of the stair tread.
Maximum 4 1 2 inch handrail projection into stairway width on either side.
Private stairways 30 inches 762 or less in height may.
Required stair width in turn depends on the number of occupants expected to exit the building.
Intermediate handrails shall be spaced approximately equally across the entire width of the stairway.
Ibc 1012 7 clear width between handrails on ramps note that this is a minimum not a maximum width.
Stair widths are based on the use and occupancy loads of adjacent spaces and must be serviced with handrails on one or both sides depending on the stair width.