A stair is a series of steps arranged in such a manner as to connect different floors of a building. Stairs are designed to provide an easy and quick access to the different floors.
A staircase is an enclosure which contains the complete stairway.
Terminologies Used During Staircase Design
A few technical terms generally used for the design of staircases are given below.
This is a portion of stair which permits ascending or descending from one floor to another. It is composed of a tread and a riser. A stair is composed of a set of steps.
It is the upper horizontal portion of a step upon which the foot is placed while ascending or descending a stairway.
It is the vertical portion of a step providing a support to the tread.
It is the vertical distance between two successive tread faces.
It is a series of steps without any platform or landing or break in their direction.
This is a platform provided between two flights. A landing extending to full width of staircase is known as half spaced landing and the space extending only half across a staircase is called a quarter space landing. A landing facilitates change of direction and provides an opportunity for taking rest during the use of the stair.
It is the horizontal distance between two successive riser faces.
This is the outer projecting edge of a tread. This is generally made rounded to give more pleasing appearance and makes the staircase easy to navigate.
They are tapering steps used for changing the direction of a stair.
It is a moulding provided under the nosing to improve the elevation of the step, and to provide strength to nosing.
It is the underside of a stair.
12. Line of Nosing
It is an imaginary line parallel to the strings and tangential to the nosings. It is useful in the construction of hand rails, giving the line with which the under surface of the hand rail should coincide.
13. Pitch or Slope
It is angle which the line of nosing of the stair makes with the horizontal.
14. Strings or Stringers
These are the sloping members which support the steps in a stair. They run along the slope of the stair.
15. Newel Post
Newel post is a vertical member which is placed at the ends of flights to connect the ends of strings and hand rail.
It is a vertical member of wood or metal, supporting the hand rails.
The combined framework of handrail and baluster is known as balustrade. This provides protection for the user of the stair.
18. Hand Rail
It is a rounded or moulded member of wood or metal following generally the contour of the nosing line, and fixed on the top of balusters.
19. Head Room
It is the minimum clear vertical distance between the tread and overhead structure (i.e. ceiling etc)
It is the total length of stair in a horizontal plane, including landings.
It is the horizontal structural member supporting stair stringers or landings.