The top of the handrail should be at least 34 inches.
Interior balcony railing height code.
Stair rails on decks should be between 34 inches and 38 inches high measured vertically from the nose of the tread to the top of the rail.
Residential properties typically require a railing of 36 inches while commercial properties should have railings between 42 and 48 inches.
The height is measured vertically above the walking surface or the line that connects the nosing of a set of stairs.
Treads must be at least 10 inches deep measuring from front to back.
Even if your balcony has additional supports potentially categorizing it as a porch or deck it must have guardrails based on the same 30 inch rule.
Railings must withstand at least 200 pounds of pressure in either direction.
Minimum required guardrail height r312 1 2 when a guardrail is required per the above explanation it must meet a minimum height requirement of no less than 36 inches for it to serve the purpose of minimizing a fall.
Requirements for deck stairs the code has some very specific requirements for deck stairs.
If your local laws follow the international residential code then balconies in your area that are 30 inches or more above the surrounding floor must have guardrails.