A. Design And Location: Stairways, porches, and terraces shall provide for safety of ascent and descent; install proper artificial light in addition to any natural light; and provide an easy run by proper proportioning of tread width to the riser height and shall meet the following requirements:
1. Headroom: Continuous clear headroom measured vertically from front edge of tread to a line parallel with stair run. Minimum: six feet six inches (6'6").
2. Width: Main stairs: Minimum two feet nine inches (2'9") clear of handrail.
3. Treads: All stairs with closed risers: nine inches (9") plus one and one-fourth inch (11/4") nosing. All stairs with open risers: nine inches (9") plus one-half inch (1/2") nosing.
4. Risers: Eight inches (8") maximum. All riser heights to be same in any stair stringer.
5. Concrete Stairs: Minimum ten inches (10") tread.
6. Stairways: (See section 8-3-24, table 2-B, of this title.)
7. Winders: Winder treads shall have a minimum tread depth of ten inches (10") measured from the nose of the tread at a point twelve inches (12") from the converging end. Winders shall have a minimum tread depth of not less than six inches (6") at any point (see section 8-3-24, tables 2-C-1 and 2-C-2, of this title). Tread width, eighteen inches (18") from converging end, shall at least equal tread width on straight stair run.
8. Circular Stairs: In addition to all the other requirements for stairs, circular stair treads shall have a minimum tread depth of ten inches (10") measured from the nose of the tread at a point twelve inches (12") from the converging end. Circular stairs shall have a minimum tread depth of not less than six inches (6") at any point (see section 8-3-24, table 2-C-3, of this title).
9. Spiral Stairs: In addition to all the other requirements for stairs, spiral treads shall have a minimum tread depth of seven and one-half inches (71/2") measured from nose of the tread at a point twelve inches (12") from the narrow end. The minimum width of spiral stairs shall be twenty six inches (26") (see section 8-3-24, table 2-C-4, of this title).
10. Landing: A landing shall be provided on each side of an exit door and shall have a minimum width and depth of three feet (3'), provided, however, a landing is not required where the exit door does not swing over the stair. The landing over which a door does not swing shall be located not more than seven and one-half inches (71/2") below the threshold level. The landing over which the door swings shall be located not more than one and one-half inches (11/2") below the threshold level.
11. Handrails And Guardrails: Handrails having minimum and maximum heights of thirty inches (30") and thirty eight inches (38"), respectively, measured vertically from the nosing of the treads shall be provided on at least one side of stairways of three (3) or more risers. Where there are no partitions on either side of the stairway, handrails are required on both sides of stairways in accordance with this section and subsection A13 of this section.
12. Decks, Porches And Balconies: Porches, balconies, or raised floor surfaces located more than thirty inches (30") above the floor or grade below shall have guardrails not less than thirty six inches (36") in height (see section 8-3-24, table 2-E and tables 3-A through 3-G, of this title; building department distributes these requirements with any deck permit application).
13. Handrails And Guardrails; Additional Regulations: Handrails and guardrails on open sides of stairways shall have intermediate rails or ornamental closures which do not allow passage of an object four inches (4") or more in diameter. Guards shall not have an ornamental pattern that would provide a ladder effect. Guardrails on open sides of stairways shall be a minimum of thirty six inches (36") high. (Ord. 2008-09-01, 9-24-2008)