Types of Stairs Used in Building Construction

Staircases are used as a way of moving from one level to another level in a building. Stairs are components of a building structure that help to serve as an emergency escape route in the case of fire. Staircase consists of a flight of steps which is considered as stairs and one or more immediate landing slabs between the levels of the floors. By arranging the stairs and the landing slabs, different types of staircases can be made for a building structure. Concrete, wood, stone, steel, or a combination of any of these components are required to make the stairs for a building structure.

Primary functions of stairs in a building structure

➢ Stairs help to provide access to the building's floors and roofs.
➢ Stairs help to provide a safe and easy means of travel among the floors.
➢ In the case of fire, stairs help to provide a suitable means of escape.
➢ In addition, stairs help to provide a means of conveying furniture and fittings between the building floors.

Different types of stairs used in building construction

There are different types of stairs used in building construction which are:

Straight Stairs

Straight Stairs are used in both commercial and residential building structures. In this case, there is only a need for the connection at the bottom and the top, any kind of intermediate supporting structure is not required.

L Shaped Stairs or Quarter Turn Stairs

This is the variation of a straight stair which can be bent at 90 degrees. To achieve this bend, a landing has been added to the transition point. This helps to provide a visual barrier between floors thus adding privacy.

U-Shaped Stairs or Switchback stairs

In the case of U-shaped stairs, the two parallel flights of straight stairs have been joined by a landing thus creating a 180-degree turn in the walk line.

Alternating Tread Stairs

These types of stairs have industrial, commercial and residential applications which help to provide a convenient way of reaching the basement, mezzanine or other spaces where the standard staircases are not fitted.

Winder Stairs

Winder stairs are a variation of L-shaped stairs. This type of stairs requires less space rather than other types of stairs.

Spiral Stairs

It has very compact designs and the treads radiate around a central pole. The installation procedure is easy and no extra support structures are required for spiral stairs.

Circular Stairs

These types of stairs are used in both commercial and residential buildings which are intended to make the design statements.

Scissor Stairs

This type of stair is effective in the case of small-footprint buildings which require two vertical means of exiting including residential apartment buildings. These types of stairs are commonly used in high-rise commercial buildings.

Cantilever Stairs or Floating Stairs

In this case, stair treads appeared to be floating in the air without any kind of support. The stair stringer has been attached to stair tread ends in this type of floating stair. This type of stair is unique and creates more visual interest.

Split Staircase or Bifurcated Stairs

This type of stair has a wide set of stairs which splits into two narrower sets of stairs at the landing leading in opposite directions. This helps to allow one staircase to act as two staircases.

Curved Stairs

These stairs are located at the entrance of the building structure to make the best impression.

Ladder Stairs or Ship stairs

Ladder stairs are very space efficient and used for tight spaces as well as in small houses. It can be built in different styles and used in a variety of spaces including lofts, docks, libraries and other places.

Calculation procedure of the staircase design

François Blondel who is a French architect understood the importance of a comfortable staircase design. As a result, Blondel developed a formula for calculating the staircase design which is known as Blondel Formula. According to this formula, the design of the staircase can be calculated by = 2 Risers + 1 Tread = 25 inches (63-65 cm).

Architects can calculate stairs by following this formula thus appropriate staircases can be made which is very pleasant to walk on.

The stair dimensions can be calculated:

Step 1: Determination of the total rise

The total vertical height should be measured to get the number of steps in the stairs.

Step 2: Calculating the step numbers

The total rise should be divided by the ideal height of each step. The rule for getting the riser height is about 7 inches / 17 cm.

Step 3: Calculating each riser’s height

The next step is dividing the total rise by the number of steps which helps to get the precise height of each riser. It needs to be ensured by the architects that the riser’s height should match the building code limits.

To learn more, watch the following video tutorial.

Video Source: The Draft

Step 4: Calculating the Tread’s width

In this stage, the Blondel Formula should be used to calculate the ideal width of the tread. In this context, the tread value can be estimated by following the formula, t = 25 – (2*r) for inches or t = 63 – (2*r) for centimetres.

Step 5: considering landings and handrails

Landing is important in case of a long staircase which helps to provide a break to change the position. This is required after a certain number of steps. Handrails are also crucial for safety in public buildings.