Minimum Inside Radius For Circular Stairs
The minimum inside
radius for circular stairs is double the distance of the tread width.
Example: If the stair tread width is 4 feet, then the inside radius
can't be less than 8 feet. From the center point of the circular stairs,
to the inside of the circular stairway (distance between two arrows in
illustration above) couldn't be less than 8 feet.
Attention: Don't forget to check with
your local building department to verify any building codes on this
website. This information could be incorrect or outdated. Building codes
are updated regularly and to some building departments have different
interpretations for certain building codes.
Acceptable Circular Stair Design
Circular Stair Design That Doesn't Meet This Particular Building Code