Code Library
Building-code answers, cited
Quick, plain-English answers to the questions contractors and homeowners ask most — each pointed at the exact IRC section. Need yours scoped to your jurisdiction? Ask Donnie.
What is the minimum ceiling height for a habitable room?
Habitable rooms must have a ceiling height of not less than 7 feet (IRC R305.1).
IRC §R305.1 →
What are the maximum stair riser height and minimum tread depth?
Max riser 7¾ inches, min tread 10 inches (IRC R311.7.5).
IRC §R311.7.5 →
What height should a stair handrail be?
Handrail height: 34 to 38 inches above the stair nosing (IRC R311.7.8.1).
IRC §R311.7.8.1 →
How tall does a guardrail (guard) need to be?
Guards must be at least 36 inches high (IRC R312.1.2).
IRC §R312.1 →
What size egress window does a bedroom need?
Min 5.7 sq ft net opening (5.0 sq ft at grade), 24 in min height, 20 in min width, sill ≤ 44 in (IRC R310).
IRC §R310.2.1 →
Where are smoke alarms required in a house?
In each sleeping room, outside each sleeping area, and on every story including basements (IRC R314.3).
IRC §R314.3 →