Stairs are the main type of communication between rooms located at different levels. All other structures (ramps, elevators) are considered special means of transportation.
The function of stairs is to ensure the movement of people. This is a guarantee of their safety and comfort. Based on this, in the process of erecting each such structure, the craftsmen are guided by the requirements and standards set forth in the special GOST and SNiP.
Stair structure elements
Despite the huge number of types and types, stairs consist of several main components:
- Flight of stairs (flight). This is the name of the inclined structure that connects the two nearest floors. There is a restriction according to which there should not be more than 12 steps in one span. The minimum quantity is three steps.
- Platform is a horizontal element, mandatory for stairs of several flights.
- Fencing - this mandatory component of the structure consists of balusters and railings. It is placed along oneor two sides of the stairs. The type, height and location of the fences are specified in the standards.
What is a landing and what is its role?
Staircases, the dimensions of which are also regulated by regulations, represent the space between two marches. The construction of a landing is necessary if the height of the linear march exceeds the allowable norm or it is planned to erect two marches at an angle to each other.
The role of the landing lies in the fact that it becomes a kind of "transit point", an intermediate element through which a climbing person can rest. In addition, this stair component is used to seamlessly connect two flights of stairs.
On various stairs (rectilinear, rotary, curvilinear) platforms are placed every 10 - 14 steps. In the case of planning structures for residential premises, the interval can be 15 - 20 steps.
Dimensions of landings
Like many other parameters, the width, depth and material of the landing is subject to regulation. The development of all these rules is based on concern for the safety and comfort of people who will use the structure.
- There are appropriate landings for each type of stairs. Their sizes are calculated based on the average width of a human step.
- Standards note that their width cannot be narrower than steps. In an extreme case, for example, when developingindividual project, the minimum platform width should be 640 mm.
- To combine two parallel marches, the width of the landing must be at least 130 mm. This is equal to almost two steps of the average person.
- Other sizes of landings (depth and length) are calculated by formulas or correlated with the width of the march.
The value of the depth parameter, as a rule, is the sum of the width of the step and one step:
Minimum depth=step width + one step length
To build a landing in the process of building a linear march, the same calculation principles are used. If it is necessary to increase the depth of large structures, it should be a multiple of the minimum depth.
Features of platforms of circular stairs or structures with non-standard steps
Often, when building a private house or a multi-level apartment, they resort to the construction of extremely beautiful (but sometimes not very convenient) spiral or spiral staircases.
It should be noted that such structures are not recommended as the main ones because climbing them is not as easy as stairs with straight flights.
The dimensions of flights of stairs and landings of helical and spiral structures are subject to extremely strict control.
In cases where the flights of stairs are at an angle of 135 to 180 degrees, the dimensions of the intermediate platforms may be less than 640 mm.
However, compliance with this size is necessary when it comes toa platform, radially divided into two halves, or in the case of the construction of two-level platforms. By the way, the difference in height between the two levels of the platform should be equal to the height of the step.
The specified minimum landing size (640 mm) is also relevant for circular and spiral stairs with goose step steps.
Stairs as a means of escape
To regulate the construction of stairs and landings in buildings where there are often a large number of people, GOST and SNiP contain particularly strict guidelines. This is due to the fact that the dimensions of the landings here are determined not only by the wishes of the developer and the designer's findings, but primarily by concern for the successful and safe evacuation of people in case of fire or other disaster.
Common requirements become:
- Compliance with the dimensions (width and depth) of the sites.
- No unnecessary items and structures on stairs with an increased risk of smoke.
- Production of outdoor and evacuation stairs from non-combustible materials.
- Sufficient illumination of the stairs using natural and artificial light sources (the size of the windows on the landings and the type of their functioning are regulated).
What should be the stairs and landings on the evacuation stairs?
Evacuation and rescue planning becomes essential when building multi-storey buildings or public buildings.
It's not just spans and landings that are subject to regulation. The dimensions (GOST defines the main parameters) of these elements, as well as the dimensions of the corridors that adjoin such structures, should not deviate from the norm.
Thus, the width of the march that can be used for evacuation should not be narrower than the door leading to it. Dimensions of landings and marches:
- For buildings of class F 1.1 (fire safety characteristic for multi-storey buildings in which a large number of people are planned to live or temporarily stay), the size is 1350 mm.
- If there are more than 200 people on the floors of the building (except the first one), then the stairs must be at least 1200 mm.
- In the case when the ladder structure goes to the workplace of one person, its width is allowed from 700 mm.
- In other cases, this indicator should have an average value of 900 mm.
What are stairs made of?
For the manufacture of stairs and their important elements (marches, balusters, railings, platforms) a large number of materials are suitable:
- Tree.
- Metal.
- Glass.
- Stone.
However, stair structures made of concrete deserve a separate description. As a rule, this material is used in the construction of multi-storey buildings and public buildings. For private houses, wood, metal, or a combination of several materials (metal with glass, wood withstone).
Concrete is a versatile material
Concrete stairs and platforms between them are often formed from prefabricated elements. Such structures are made of high-grade material (minimum B15), and are also equipped with a metal frame.
Reinforced concrete products are produced by factories and enterprises, whose activities are strictly regulated, so the developer does not have to worry about compliance with manufacturing rules. However, the correct assembly and fixing of structures depends only on the qualifications of the master builders.
Concrete slabs of landings (dimensions are selected taking into account the dimensions of the building and the width of marches) are used in the construction of brick and concrete buildings, as well as in cases of using combined techniques.
Their strength, ease of use and wide possibilities for decoration significantly speed up and facilitate the construction process.
Reinforced concrete landings (dimensions do not affect performance) are recommended for making internal and external stairs. However, it should be borne in mind that reinforced concrete products will be able to maintain their properties in the absence of aggressive environmental conditions. The maximum allowable air temperature should not be lower than -40 degrees.
Decoration of landings
A ready-made concrete staircase installed inside a dwelling is sheathed with wood panels, painted or carpetedcover.
Stair structures lined with ceramic tiles, laminate or parquet board serve well and for a long time.
The use of wood or metal as a material for stairs requires the obligatory painting of the finished product. Based on the characteristics of the material, the necessary paints are selected:
- Simple paints for metal.
- Emulsions and impregnations for wood.
- Special paints for the corresponding type of wood.
A great way to decorate and increase the safety of the flight of stairs and landings is the placement of lighting. Most often, LEDs (separate lamps or tapes) are chosen for this purpose. They are attached along the railing, around the perimeter of the site or down on the steps.
