A graspable ADA-compliant secondary handrail is an important component to consider when planning a deck with stairs. So whether you're constructing a residential composite deck, lumber deck, or a deck made from another decking material, you're typically required to install a graspable secondary handrail on one side of the deck's stair railing when there are four or more stair risers present.
Stairways having four or more risers, or rising more than 30" in height, whichever is less, must have at least one grab rail.
Handrails with a circular cross-section shall have an outside diameter of at least 11⁄4” but not greater than 2". If the handrail is not circular it shall have a perimeter dimension of at least 4" but not greater than 61⁄4”, with a maximum cross-section dimension of 21⁄4”.
The grab rail must terminate at the newel post (top & bottom posts).
Clear space between a handrail and a wall or other surface shall be a minimum of 11⁄2”.
The height of handrails must be installed 34" to 38" from the upper surface of the handrail to the surface of the tread. Graspable secondary handrails are required by more and more building codes / deck codes in areas across the country.
As always, check your local building code or ask your building inspector to make sure a secondary handrail is installed when required by law.