STAIRS AND STAIR STAIRS AND STAIR FRAMINGFRAMING

Lesson ObjectivesLesson Objectives

Describe what stair construction is.Describe what stair construction is.

Define terms associated with stair Define terms associated with stair construction.construction.

Calculate the unit rise, unit run, angle of Calculate the unit rise, unit run, angle of incline, and number of treads for a incline, and number of treads for a stairway given the total run and rise.stairway given the total run and rise.

STAIRSSTAIRS

STAIR – a series of steps, each elevated a STAIR – a series of steps, each elevated a measured distance, leading from one level measured distance, leading from one level of a structure to another.of a structure to another.

““Flight of Stairs” – a continuous series of Flight of Stairs” – a continuous series of steps without breaks formed by landings steps without breaks formed by landings or other constructionsor other constructions

STAIRSSTAIRS

Types of StairsTypes of Stairs– Main StairsMain Stairs

Straight Run, Platform, and WindingStraight Run, Platform, and Winding

– Service StairsService Stairs

Stairways are usually not built or installed Stairways are usually not built or installed until after interior wall surfaces are until after interior wall surfaces are complete and finish flooring has been laid.complete and finish flooring has been laid.

Stair TerminologyStair Terminology

Stairwell – the rough opening in the floor above Stairwell – the rough opening in the floor above to provide headroom for stairsto provide headroom for stairs

Stringer – one of the inclined sides of a stair that Stringer – one of the inclined sides of a stair that supports the risers and treadssupports the risers and treads

Riser – the vertical surface between two treadsRiser – the vertical surface between two treads

Tread – the horizontal face of one stepTread – the horizontal face of one step

Stair TerminologyStair Terminology

Nosing – the part of the tread that extends over Nosing – the part of the tread that extends over the riser beneath itthe riser beneath it

Newel – the post that supports the railingNewel – the post that supports the railing

Handrail – an angled piece supported by a wall Handrail – an angled piece supported by a wall or railing intended to be grasped by persons or railing intended to be grasped by persons

Balusters – vertical members supporting the Balusters – vertical members supporting the handrail on open stairshandrail on open stairs

Stair TerminologyStair Terminology

Platform – a horizontal area placed between to Platform – a horizontal area placed between to flights of stairsflights of stairs

Landing – the floor at the top or bottom of each Landing – the floor at the top or bottom of each story where a flight of stairs begins or endsstory where a flight of stairs begins or ends

Winders – Wedge-shaped treads installed where Winders – Wedge-shaped treads installed where stairs turnstairs turn

Unit Run – the width of a tread minus the nosingUnit Run – the width of a tread minus the nosing

Stair TerminologyStair Terminology

Unit Rise – the height or a riser; vertical distance Unit Rise – the height or a riser; vertical distance between two treadsbetween two treads

Total Run – the sum of all unit runsTotal Run – the sum of all unit runs

Total Rise – the sum of all unit risesTotal Rise – the sum of all unit rises

Headroom – the vertical distance from a step to Headroom – the vertical distance from a step to a ceiling abovea ceiling above

Rough OpeningRough Opening

The rough opening for the The rough opening for the stairwell must be carefully stairwell must be carefully laid out and constructedlaid out and constructed

Trimmers and headers Trimmers and headers should be doubled for should be doubled for supportsupport

Designing StairsDesigning StairsStair Angle should fall between 30 and 35 Stair Angle should fall between 30 and 35 degreesdegreesThe sum of two risers and one tread should be 24 The sum of two risers and one tread should be 24 to 25”to 25”The sum of one riser and on tread should equal The sum of one riser and on tread should equal 17 to 18”17 to 18”An 11” run and a 7” rise follows all three rules.An 11” run and a 7” rise follows all three rules.The stair width should be a 3’ minimum with a 3’2” The stair width should be a 3’ minimum with a 3’2” – 3’4” preferred width– 3’4” preferred widthHeadroom for a main stairwell should be a Headroom for a main stairwell should be a minimum of 6’8”minimum of 6’8”

How many steps do I need?How many steps do I need?

What is the total rise from 1What is the total rise from 1stst floor to floor to second floor? _______ second floor? _______

What is the rise of each step? ________”What is the rise of each step? ________”

Calculate the steps needed:Calculate the steps needed:

Total Rise from 1Total Rise from 1stst to 2 to 2ndnd floor floor = # Steps = # Steps

Rise of each Step Rise of each Step