Stairs can be permanent or non-permanent.
Permanent stairs are usually used to connect:
two horizontal planes in the building
different building floors
This type of ladder consists of steps that have the same height. Stairs can be straight, letter “L”, the letter “U”, rotate or is a combination. The components of the stairs include the height of the tread (riser), the width of the tread / depth (tread), landing (landing), nosing, handrail (handrail) and the safety area (balustrade). Examples of the use of these stairs, for example, as we find in residential buildings or offices, “monkey stairs”, etc.