Stairways: Elements and types
Before going into any details, we are going to define what a stairway is. Stairways are construction elements that provide communication between two spaces located at different heights.
As we will see later, stairways may be made of various materials that include steel, marble and concrete etc.
Stairways are made up of various elements as described below:
The steps of a stairway are located on various levels to allow going up or down the existing level difference. Steps consist of two elements:
This is the horizontal part of the step.
The stair riser
This refers to the vertical part of the step.
As can be seen from the drawing, the stairway box refers to the area or surface of this, in other words the space that includes the stairway.
This is the succession of steps between two horizontal planes.
This refers to the horizontal plane located at the end of each section that is on the same plant level to which it leads.
The horizontal plane at the end of each stairway section.
Also known as the stairway cavity, which refers to the central cavity between the various stairway sections.
The pass width of a stairway.
First step of a stairway
This is the stairway support area located at the start of each level.
If the stairway support commences with the first step, then the stairway landing is the destination point.
Line of travel
This is an imaginary line that describes the travel made by a person going up or coming down stairs using the handrail. The line of travel is approximately 40 cm.
The free vertical height between the horizontal plane (tread) and the ceiling. The minimum height is 2.20 metres.
A stairway without a well.
Types of stairways
Four types of stairways can be established according to:
- The form with respect to the building, in other words, the form of the corresponding entrance stairway.
- The form with respect to the building plan. In this case, it refers to its interior.
- The construction material
- The elements that support the stairway
Type of stairway with respect to the building
These are outside stairways that provide access to a building in a higher level. In such a case, the following distinction may be made:
When the stairway is located perpendicular to the façade
Here, the stairway is joined to the building, which can also be accessed by one side or by both.
Type of staircase with respect to the plan
· Having a straight section
· Two straight sections
· Two return sections without stairwell
· Two return sections with stairwell
· Three or four sections
Stairways according to the employed construction material
· Marble or granite
Example of a marble stairway:
Stairways according to their support elements
The steps are supported on surfaces formed by inclined slabs or frameworks.
The steps rest on inclined beams, with one or more beams per section.