• Contact Information

    Jefferson County Building Safety


    Monday - Friday
    7:30 a.m. - 5:30 p.m.

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    100 Jefferson County Parkway
    Suite 3540
    Admin and Courts Facility
    Golden, CO 80419-3540

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  • Stairways


    From the 2015 International Residential Code unless otherwise indicated. 

    R311.7.1 - Width

    Stairways shall not be less than 36 inches (914 mm) in clear width at all points above the permitted handrail height and below the required headroom height. Handrails shall not project more than 4.5 inches (114 mm) on either side of the stairway and the clear width of the stairway at and below the handrail height, including treads and landings, shall not be less then 31.5 inches (787 mm) where a handrail is installed on one side and 27 inches (698 mm) where handrails are provided on both sides.

    R311.7.2 - Headroom

    The headroom in stairways shall not be less than 6 feet, 8 inches (2032 mm), measured vertically from the sloped line adjoining the tread nosing or from the floor surface of the landing or platform on that portion of the stairway. 

    R311.7.5.1 - Risers

    The riser height shall not be more than 7 3/4 inches (196 mm).

    R311.7.5.2 - Treads

    The tread depth shall not be less than 10 inches (254 mm).

    R311.5.3 - Nosings

    Solid risers less than 11 inches require a nosing not less than 3/4 of an inch or more than 1 1/4 of and inch 


    Last Updated: 5-3-2017