Building Code Definitions for Handrail
The purpose of a handrail is to provide guidance. It is required on stairs with two or more risers and ADA ramps with a rise of 6″.
In commercial applications, handrail is required on both sides of stairs and ramps. They are not required on walking surfaces with running slope less than 1:20.
Height: Placed between 34″ and 38″. Measurement must be taken from the stair nosing or walking surface. (Note: OSHA requires handrail to be between 30″ and 34″ above the stair nosing.)
For children, the 2010 ADASAD recommends a maximum height of 28″ with a minimum of 9″ of clearance between the child’s rail and the adult rail.
Continuity: Handrail must be continuous within the full length of each stair flight or ramp run. Inside handrails on switchback or dogleg stairs and ramps shall be continuous between flights or runs. They are not to be obstructed along their tops or sides.
Intermediate Rails: All portions of an egress path must be within 30″ of a handrail (will vary based on building occupancy)
Size Limitations: Handrail size is now consistent between all codes and standards: 1-1/4″ to 2″ diameter or Provide Equivalent Graspability.
Equivalent Graspability is defined as: Handrail gripping surfaces with a non-circular cross section shall have a perimeter dimension of 4 inches (100 mm) minimum and 6″ maximum, and a cross-section dimension of 2-1/4″ (57mm) maximum.
For Residential Applications, the ICC permits the use of larger sections that meet the Type II Definition as noted in the image above. This applies to sections with a perimeter greater than 6-3/4″.
Structural Requirements: All codes and standards are consistent with their requirements for loading — 50 lb/ft uniform load or 200 lb. concentrated load.
In all installations, always check with your local Authority Having Jurisdiction (AHJ) to confirm what is being applied for your application.Tony Leto