6.5 Stair Handrails: Location, Height, Profile, Continuity, and Extensions

6.5 Stair Handrails: Location, Height, Profile, Continuity, and Extensions

Handrails appear in two places on the ICC 21 outline: ramp handrails under Accessible Routes (Section 4.2 of this guide) and stairs and handrails under General Site and Building Elements. This section concentrates on the general Section 505 criteria and their application at stairways. The IBC counterpart is Section 1014, which the 2024 edition renumbered because it inserted a new 1014.3 (lateral location).

Where Handrails Are Required

• A117.1 504.7: Accessible stairs have handrails complying with 505.
• A117.1 405.8: Ramp runs with a rise greater than 6 in. have handrails complying with 505.
• A117.1 505.2: Handrails are on both sides of stairs and ramps. Exceptions: in assembly seating areas, aisle stairs need a handrail only at the side or within the aisle, and ramped aisles serving seats do not need handrails on the sides.
• IBC 1014.1: Handrails are provided for stairways and ramps as required by 1011.11 and 1012.8.
• IBC 1014.9 (2021) / 1014.10 (2024): Stairways have intermediate handrails so all portions of the required width are within 30 in. of a handrail.

Height, Clearance and Profile

Continuity (A117.1 505.3 and 505.6)

• Handrails are continuous within the full length of each stair flight or ramp run.
• Inside handrails on switchback or dogleg stairs and ramps are continuous between flights or runs.
• Other handrails comply with the extension rules (505.10) and with Section 307 protruding objects.
• Gripping surfaces are continuous, without interruption by newel posts, other construction elements or obstructions (505.6), except:
  1. Brackets or balusters attached to the bottom of the handrail are not obstructions if they obstruct 20 percent or less of the handrail length, their horizontal projections are 1 1/2 in. minimum below the bottom of the handrail (reduced by 1/8 in. for each 1/2 in. of perimeter above 4 in.), and edges are rounded;
  2. Along walking surfaces not steeper than 1:20, the bottoms of handrails may be obstructed along their full length where they are integral to crash rails or bumper guards.
• Exception to continuity: handrails in aisles serving seating may be discontinuous to provide access to seats and crossovers.

Extensions (A117.1 505.10)

Extensions are not required at continuous inside turns, in aisles serving seating where handrails are discontinuous, or, in alterations, where full extensions would be hazardous due to plan configuration. IBC 1014.6 (2021) / 1014.7 (2024) states the same top, bottom and ramp extensions and exempts handrails within dwelling units that are not required to be accessible, which may run only from the top riser to the bottom riser.

A117.1-2017 does not require an added horizontal segment after the one-tread-depth bottom extension: the bottom extension continues at the stair slope for one tread depth and then returns or continues to the next flight.

Worked Example

A new exit stair with 11-inch treads uses 1 1/2-inch steel pipe handrails (1.9 in. outside diameter) on both sides, mounted with 1 1/4 inches of clearance to a CMU wall, 36 inches above the nosings. At the top, the handrail stops directly above the top nosing; at the bottom, it extends 11 inches at the stair slope and returns to the wall.

• Profile and height comply.
• Clearance fails: 1 1/2 inches minimum is required.
• Top extension fails: the handrail must extend 12 inches horizontally beyond the landing nosing.
• Bottom extension complies: one tread depth (11 inches) at the slope of the flight, then a return.