Section 410.520 - Protective Railings and Walls(A) Every owner of a residence shall provide:(1) A safe handrail on at least one side of a stairway as required by 780 CMR: Massachusetts State Building Code.(2) A wall or guard no less than 30 inches in height on the open side of all stairways replaced or constructed before August 28, 1997. Any such guard replaced or constructed after August 28, 1997 shall be not less than 34 inches in height.(3) A wall or guard no less than 36 inches in height, enclosing every porch, balcony, mezzanine, landing, roof deck or similar place, which is 30 inches or more above the ground. Any such wall or guardrail along open sided floor areas, mezzanines and landings in Use Group R-3, replaced or constructed after August 28, 1997, shall not be less than 42 inches in height.(B) All guards and balusters must be placed at intervals of no more than four inches, or six inches if constructed before August 28, 1997. Ornamental patterns between the guardrail or handrail and floor or stair may not allow for a sphere four inches in diameter to pass through the opening or six inches in diameter if constructed before August 28, 1997.(C) Balusters or ornamental work constructed or replaced after August 28, 1997 may not be constructed so as to create a horizontal climbing risk (a "ladder effect") notwithstanding any other regulatory provision to the contrary.Adopted by Mass Register Issue 1495, eff. 5/12/2023.