3 STAIRSSTAIR – a series of steps, each elevated a measured distance, leading from one level of a structure to another.“Flight of Stairs” – a continuous series of steps without breaks formed by landings or other constructions
4 STAIRSTypes of StairsMain StairsStraight Run, Platform, and WindingService StairsStairways are usually not built or installed until after interior wall surfaces are complete and finish flooring has been laid.
5 Stair TerminologyStairwell – the rough opening in the floor above to provide headroom for stairsStringer – one of the inclined sides of a stair that supports the risers and treadsRiser – the vertical surface between two treadsTread – the horizontal face of one step
6 Stair TerminologyNosing – the part of the tread that extends over the riser beneath itNewel – the post that supports the railingHandrail – an angled piece supported by a wall or railing intended to be grasped by personsBalusters – vertical members supporting the handrail on open stairs
7 Stair TerminologyPlatform – a horizontal area placed between to flights of stairsLanding – the floor at the top or bottom of each story where a flight of stairs begins or endsWinders – Wedge-shaped treads installed where stairs turnUnit Run – the width of a tread minus the nosing
8 Stair TerminologyUnit Rise – the height or a riser; vertical distance between two treadsTotal Run – the sum of all unit runsTotal Rise – the sum of all unit risesHeadroom – the vertical distance from a step to a ceiling above
12 Stair Layout Measure total rise (from landing point) Decide on number of risers based on 7” to 7 ½” risers (unless special circumstances prevent this)Divide total rise by # of risers for riser heightSubtract # of risers by 1 for # of treadsSet stair jacks on framing square and trace onto stringerAdd and subtract as needed for top and bottom to adjust for actual floor heights
13 9’ 2” 9’ 2” = How many inches total rise? 110” What is the standard height of a step?7” to 7 ½”Divide total rise by standard riser height110” / 7” = 15.71110” / 7 ½” = 14.6So… 15 risers and 14 steps110” / 15 = 7.3” = single riser heightAnd standard 11” tread w/ nosing9’ 2”