While in-home stair-rail height can be somewhat subjective, limitations and restrictions vary from state to state and county to county. Some cities also impose their own regulations. For example, in certain Arizona and California counties, a poorly worded stair code makes the typically standard 2 5/8-inch stair rail "too wide" to be legal.

On the Other: OSHA Guidelines

The Occupational Safety and Health Administration (OSHA) more closely governs stair rails in public facilities. Until a 1990 revision in policy, OSHA required stair rails to be between 30 and 34 inches high. This requirement also applied to handrails on stairs. Then, lawmakers determined that, for new installations, hand rails must be at least 36 inches from the top surface of the rail to the surface of the staircase. Plus, the new guidelines state that stair rails between 36 and 37 inches can double as handrails.

Bottom Line

If you're installing a stair rail yourself, be sure to double check the rules and regulations for your city, county and state before you get started. While areas differ slightly in their detailed preferences, most mirror OSHA's guidelines.

Source:

Westfire Inc.: Stair Codes

2005 OSHA Letter: Conditions Under Which a Stair Railing Can Also Serve as a Handrail

Resource:

Safetyis.us: Stairs and Stairways Checklist