RAILING, STEPS, AND LANDING REQUIREMENTS FOR 1 & 2 FAMILY DWELLINGS AND COMMERCIAL PER 780 CMR 9TH EDITION.
780 CMR R 312 - Guardrails
Guardrails are required for anything over 30 inches high.
Guardrails need to be at least 36 inches high
Spacing between balusters - Cannot allow an object 4 inches or more in diameter to pass through. (780 CMR R 312.1.3)
Handrail Grip Size - Cross section with outside diameter of at least 1 1/4 inches and not more than 2 inches. (780 CMR R 311.7.8.3)
STAIRWAYS/STEPS FOR 1 & 2 FAMILY DWELLING
Stairways shall not be less than 36 inches in clear width. (780 CMR R 311.7.1)
780 CMR R 311.7.5.1 & R 311.7.5.2:
Maximum riser height shall be 8 1/4 inches.
Minimum tread depth shall be 9 inches
780 CMR R 311.3:
Landings - Interior Landing – 36 inches x 36 inches
Exterior Landings – 36 inches wide by 42 inches deep
The floor area or landing shall not be more than 1 1/2 inches lower than the top of the threshold on the interior side nor more than 8 1/4 inches lower than the threshold on the exterior side.
STAIRS FOR OTHER THAN 1 & 2 FAMILY DWELLINGS IN A THREE OR MORE DWELLING UNIT AND COMMERCIAL STAIRS (EXCLUDING FIRE ESCAPES)
Maximum riser height shall be 7 inches – Minimum 4 inches
Minimum Tread depth shall be 11 inches
STAIRS: See 780 CMR 1011
GUARDRAILS: See 780 CMR 1015
HANDRAILS: See 780 CMR 1014