Standards for Stair Railings

Codes

• Though local, state and some federal codes dictate the standards for stair railings, most base their guidelines either directly or with some changes on the International Residential Code or IRC. The International Code Council, founded in 1994, developed these standards to help “the building safety community and construction industry provide safe, sustainable and affordable construction.” The organization also creates other construction guidelines that may effect stair railings, including the International Building Code, International Fire Code and International Property Maintenance Code.

Basics

• The 2012 IRC states that handrails must rise from 34 inches through 38 inches from the sloped plain either next to the stair tread nosing or on the adjoining ramp. Stair rails can exceed the maximum only when they provide a continuous transition between flights of stairs, or from stair rails to guard rails. The width of the stairway above the handrail must be 36 inches or more up to the required headroom height. Handrails cannot project more than 4.6 inches on either side of the stairway. Neither must they reduce the width of the stairway below the handrail to below 31.5 inches for one handrail, or 27 inches for handrails on both sides.

Grip

• Type I handrails with circular cross sections must have an outside diameter of between 1.25 to 2 inches. Handrails without circular cross sections must have perimeters measuring between 4 inches and 6.25 inches, with a maximum cross-section dimension of 2.25 inches. Type II handrails have perimeters of more than 6.25 inches and must have graspable finger recess areas on both sides of their profile. These recesses must start at 0.75 inches, measured from the tallest part of the rail, and be at least 0.31 inches deep. The recessed area must continue for a minimum of 0.37 inches to a level at least 1.75 inches below the tallest part of the rail.

Disabilities

• Though individuals in wheelchairs cannot use stairs, those with balance, vision or hearing problems may. The Americans with Disabilities Act, or ADA, modifies IRC codes so the disabled can access stairways. The codes are mandatory for commercial buildings, but exist only as guidelines for one- and two-family residences. Heights and measurements for gripping surfaces match the IRC standard. However, where the IRC allows a minimum of one handrail, the ADA requires two: one on either side of the stairway.