What is staircase construction?

Stair is a type of vertical transportation in a building which consist of a series of steps in a flight of stairs that enable the vertical movement of people and materials from one floor to another. A staircase consists of steps that comprises of riser & tread, handrail, baluster, stair stringers, newel post and waist slab. The construction of staircase with all the components is termed as stair construction. A staircase is an enclosure that contains the entire stairway. The materials used for the construction of stairs are bricks, reinforced cement concrete, stone, lumber, steel and a combination of these materials.

Components of Staircase

• Step

It is made up of the riser and tread or going. This allows users to get from one floor to another by ascending or descending.

• Flight

The series of steps that does not have any break or landing in between is termed as a flight.

• Tread

The horizontal member of the step which is used for ascending or descending is called as tread. The distance between the top of one tread and the adjoining tread is termed as tread rise. The width of the tread after subtracting nosing is called as run of the stair.

• Riser

The vertical member of the step that is placed in between two treads is called as a riser and the distance between them is called as stair rise. Sometimes the riser is omitted in the step (no riser is provided) and such type of staircase is called as open staircase. A single riser height is also termed as unit rise. The total rise is divided by the number of risers to get the unit rise.

• Nosing

The part of the tread that project beyond the riser. They add length to the tread without affecting the pitch of the stairs and give the staircase a more attractive appearance.

• Stair stringers

The sloping member that supports the steps is called as stringers. It is also called as string. The total horizontal length of the stringer is termed as total run. Stringers supports the risers and treads. The inner stringer is against the wall, while the outer stringer is visible from the side of the stairs.

• Winders

The tapering steps that are used to change the direction of stair are called winders.

• Total rise

The vertical distance between the bottom of the first step and the top of the final landing is the total rise of a set of steps. Between landings or floor levels, the Total Rise should not exceed 151 inches.

• Handrail

The inclined member which is placed for handhold to provide support is called as handrail. It is also known as banister.

• Railing

Railings are provided to support a handrail and it acts as a safety barrier.

• Baluster

The vertical member supporting the handrail. The combined framework of a baluster and handrail together is termed as a balustrade.

• Newel post

The vertical post placed at the starting and ending of a handrail parallel to the flight of the stair.

• Landing

It is a platform provided near the topmost and the bottom of the stair of a flight. A tiny platform erected as part of the stair between main floor levels known as an intermediate landing, it is often used to allow staircases to change directions or to provide the user a momentary relaxation.

• Headroom

The minimum clear height from a tread to overhead construction is called as headroom.

Stair Framing and Layout

The stair laying and framing consists of the following

• Width of stair

Stairways for non-residential purpose must have a minimum width of 1,200 mm and a distance of 1,000 mm between railings. If the stairwell is greater than 2 meters broad, it should be separated into two flights of at least 1,000 millimeters. For residential purpose the width should be at least 900 mm. Landings should have at least the same breadth and length as the flight's minimum width. Each landing should have an unobstructed length of at least 1.200 m for structures other than homes.

• Length of Flight

Stairs with more than 36 risers in a row should have at least one direction change between flights. The maximum number of risers between landings for structures other than homes should be 16 for utility stairs and 12 for general access stairs.

• Dimensions of steps

In a residential structure, no stair may have a riser height of more than 0.20 meters and a tread of less than 0.25 meters. A stair in a commercial, public, or industrial building must have a unit rise of 0.18 meters and a tread of 0.27 meters. In public buildings, warehouses, and industrial structures, all stairwells and walls surrounding stairwells must be made of fire-resistant materials.

• Location of staircase

No component of a building's second or higher storey should be more than 30 meters from a stairway framing or ramp leading to the ground floor.

• Ventilation of staircase

Every stairwell must be properly ventilated.

• Headroom in staircase

Any staircase must have at least 2.20 meters of unobstructed headroom measured from the top of the riser to the most dependent component of the ceiling above.

• Provision of hand rails

The laying of the handrail must be at least one on every stairwell. Handrails are not required if steps from the ground to the building are supplied if the steps do not exceed 1.5 meters in length and are not less than 1 meter in width.

Context and Applications

The topic of stair construction and layout has significance in all that is considered with vertical movement of people and object, mainly in structures and buildings. The topic is taught in the following fields of study.

• Bachelor of Engineering in Civil Engineering
• Master of Engineering in Structural Engineering
• Bachelor of Architecture

Practice Problem

Q1) The staircase surrounded by walls is called as

1. Stairway
2. Top riser
3. Bottom riser
4. Joist

Answer: Option a

Explanation: It is a passage that consists of series of steps and leads from one floor to another. The remaining options indicate the parts of the staircase.

Q2) The horizontal distance between two risers is termed as

1. Pitch
2. Stair Stringers
3. Going
4. Newel post

Answer: Option c

Explanation: The horizontal distance or width of tread between two successive risers is termed as going. Pitch indicated the slope of the staircase, a stringer is the sloping member that supports steps and newel post is a member that supports the handrail.

Q3) How-to name the stair which rests on a foundation and are attached to a decking by means of hangers.

1. Deck stairs
2. Stringer
3. Building stairs
4. None of the above

Answer: Option a

Explanation: Deck stairs are those that are attached to wooden or timber decking. The layout of the deck consists of risers, treads and railings.

Q4) The underside of the stair is called as

1. Tread
2. Soffit
3. Winders
4. Stair Stringers

Answer: Option b

Explanation: Soffit is name for the underside of the staircase.

Q5) Which of the following equipments are used for cutting the tread and stair stringers?

1. Handsaw
2. Circular saw
3. Both a and b
4. None of the above

Answer: Option c

Explanation: Both equipments are used to cut tread and stringer of the staircase.