Installation Guide

Mylen Code Stair Packages will address and meet compliancy with
each of the requirements that are listed below. This information will
apply to the BOCA Code, UBC Code, IRC, and IFC codes.
1. Minimum clear walking path of 26 inches. A 5-foot diameter or larger
stair will provide this width.
2. Each tread will have a minimum of 7 1/2-inch tread depth at 12 inches
from the narrow edge.
3. All Treads will be identical.
4. The tread rise shall not be more than 9 ½ inches high.
5. Minimum headroom of 6 foot 6 inches shall be provided, measuring
plumb from the edge of the platform down to the tread below
6. Landing width shall not be less than the required width of the stairway.
Minimum spiral stair tread width is 26 inches.
7. Stair balusters shall be spaced so a 4-inch object cannot pass between.
The IRC Code permits a 4 3/8-inch space.
8. Balcony / well enclosure guardrail balusters shall be spaced so a 4-inch
object cannot pass between.
9. Balcony / well enclosure guardrail height shall not be less than 36
inches. (If your state or municipality requires 42-inch tall guardrails, the
sales order must reflect this detail).
10. The stairway shall be equipped with one handrail on the wide edge of
the tread.
11. Handrail height, measured vertically from the tread nosing, shall not be
less than 34 inches and not more than 38 inches.
12. Handrail grip size. Type I-Handrails with a circular cross section shall
have an outside diameter of at least 1 1/4 inches and not greater than 2
inches. (Mylen’s standard circular handrail is 1 1/2 inch diameter. This
will address the UBC minimum cross section of 1 1/2 inch diameter.)
13. A 300 lb. concentrated load is required. On request, our sales
department can provide structural calculations for your job
specifications.
*Mylen’s standard code package does not address the open space between
each tread (open rise stair). If your local building code requires no more
than 4” space in this area, please call [phone] to have riser bars
included in your order or speak with our customer support team for other
options.
BUILDING CODE SPECIFICATIONS
Visual Interpretation of IRC Code
Mylen Spiral Stairs Comply with National Building Codes
R311.5.8.1 Spiral Stairs. Spiral stairways are permitted, provided the
minimum width shall be 26 inches (660 mm) with each tread having a 7
1⁄2 inch (190 mm) minimum tread depth at 12 inches from the narrower
edge. All treads shall be identical, and the rise shall be no more than 9 1⁄2
inches (241 mm). A minimum headroom of 6 feet, 6 inches (1982 mm)
shall be provided (See above diagram).
Visit mylenstairs.com for more information or call [phone] to speak with a
customer or product support member.
Handrail
Height
(34” Min. to
Max. 38”)
9 ½” Max.
Rise
Max. 4”
Sphere
Min.
Headroom
6’6”
Min. 36”
Platform Rail
Height
*4” Max.
Open Space