M-Tech Engineering Ltd , Unit 1, Third Avenue, Greasley Street, Bulwell, Nottingham UK, NG6 8ND Phone 0115 9794448      Fax 0115 9794449 Staircase Terminology • Helical - A stair which curves around a helix from one level to the next by the aid of two stringers either side of the treads.   • Spiral - A curve that winds around a fixed centre point usually a centre pole, at a continuously pitch. • Cantilevered – A single string which is usually hidden in the wall projecting the tread horizontally and supported at one end only giving the impression of the tread floating. • Balustrade - The collective name for the complete assembly of handrail, posts and infill components. • Cut or saw tooth String - A string with the upper and/or lower edge cut away to the profile of the treads and risers exposing the profile from the side. • Closed String - A string which hides the treads and risers so their outline cannot be viewed. • Wall String - The string of a staircase that is fixed flush with the outside or inserted/hidden within a wall. • Tread - The top or horizontal surface of a step • Floor to floor - The vertical distance between the floors or landings connected by the flight. • Rise - Is the vertical measurement from the top of the tread to the top of the tread • Riser - A component that sits between 2 treads to either split or fully enclose the gap between the treads. • Going - is the horizontal distance between the face of one tread to the face of the tread above. • Nosing – Is the top front edge of each tread. • Pitch Line - The notional line connecting the nosing’s of all treads in a flight of stairs. • Pitch - The pitch is the angle between the pitch line and the horizontal