Maximum Projection of Railing From Wall. Temporarily attach the header plate with lag bolts. Pennsylvania Law Office Cable Railing Viewrail Floating Staircase Staircase Floating Stairs Check to ensure that the treads stringer are parallel with the adjacent wall. . However the ICC notes that if the steps do not have nosings and the steps have solid risers not open risers the minimum tread depth is 11 inches. This distance must be at least 10 inches. As Andy deliberates where to leave the goods she turns to see Mirandas daughters peering down a four-story curved staircase. The Australian standards for stairs and landings state that you can use a maximum of 18 stairs risers in a single flight. Because floating stairs have empty space underneath and between the steps theres a greater chance for injury while climbing the stairs. 34 to 38 inches. Floating stairs or open-riser staircases are safe for children as