Architecture
Stair Handrail Height Guide
Quick reference for handrail and guardrail height requirements under the International Building Code (IBC) and International Residential Code (IRC). Always verify with your local AHJ.
⚠️ This is a reference guide only. Building codes vary by jurisdiction and are updated regularly. Always confirm requirements with your local Authority Having Jurisdiction (AHJ) before construction.
Residential Stair Handrails
IRC Section R311.7.8
Handrail Height
Measured vertically from stair nosing
34–38 in
(864–965 mm)
(864–965 mm)
Required When
4+ risers
Graspable Profile
Circular or non-circular compliant profile
Required on 1 side
Handrail Width (circular)
1¼–2 in Ø
Non-circular Perimeter
4–6¼ in
Clearance from Wall
1½ in min
Handrail Extensions
At top: per horizontal run; At bottom: beyond last riser
Residential Guardrails
IRC Section R312
Guardrail Height
Open sides of stairs, landings, balconies
36 in min
(914 mm)
(914 mm)
Required When
Open sides more than 30 in above floor
30 in threshold
Opening Limits
Intermediate balusters
4 in max sphere
At Stair Openings
4⅜ in sphere max
Commercial Stair Handrails
IBC Section 1014
Handrail Height
34–38 in
(864–965 mm)
(864–965 mm)
Required On
Both sides of stairs
Circular Handrail Diameter
1¼–2 in Ø
Non-circular Perimeter
4–6¼ in
Clearance from Wall
1½ in min
Projecting into Required Width
4½ in max per side
Handrail Extensions
Top and bottom extensions required
Required per IBC 1014.6
Commercial Guardrails
IBC Section 1015
Guardrail Height (general)
42 in min (1067 mm)
Guardrail — Stairs
34–38 in handrail; 42 in guard
Required When
30 in above adjacent grade
Opening Limits
4 in max sphere
Assembly Occupancies
Standing or fixed seating above 30 in
26 in (with seat rows below)
ADA Stair Handrail Requirements
ADA Standards §504, §505
Handrail Height
34–38 in
(864–965 mm)
(864–965 mm)
Required On
Both sides
Circular Cross Section
1¼–2 in Ø
Non-circular Perimeter
4–6¼ in max
Clearance from Wall
1½ in min
Top Extension
12 in min horizontal beyond top riser
Bottom Extension
Slope of stair, beyond last riser one full tread depth
Return Ends
Returned to wall, post, or floor
Interruption
Continuous within full length of stair