Internal and external stairs are available in almost every home. It is necessary to assemble such structures with a preliminary drafting of the project. When developing drawings, it is important to comply with all the standards provided for by SNiP and GOST. In particular, this applies to such an element of the design of the stairs as steps. First of all, they must be strong and reliable. The dimensions of the steps of the stairs of the flight of stairs and the opening should be selected in such a way that it is convenient to move along them. In addition, their design must also be as safe as possible.
Types of stairs
In the yards and in the interior of houses, lifting structures of the following types can be installed:
- Marching. This is the most common type of stairs. Their steps are usually attached to a kosour or bowstring. Marching stairs can be simple and rotary. If it is impossible to arrange the site due to lack of free space, such structures are made curved using winder steps.
- Screw. This option looks more modern than the marching one and takes up much less space. Installed spiral staircasescan be in any part of the house or yard, and not just near the wall. They are usually round in shape. The steps in such stairs are trapezoidal and are attached to the central pole. Sometimes rectangular spiral staircases are also installed in houses and courtyards. In this case, two sites are included in their design. Unfortunately, this option is cumbersome and therefore rarely used.
- Vertical. This type of ladder is usually used as a fire ladder, for climbing to unheated attics or descending into cellars. Such stairs are simply two supports, between which the rungs are stuffed. There are two main varieties: attached and stationary. Often such stairs are made folding.
Master turning stairs are quarter (90 degrees) and half-turn (180 degrees). Screw structures, in fact, are their variety. The rotation of such stairs is carried out by 180 gr. Next, let's see what the dimensions of the steps can be in all these cases. GOST determines the exact indicators mainly only for the stairs of multi-storey buildings. In particular, in most cases, the optimal (but not beyond the requirements of SNiP) width, length, depth and height are selected.
General Requirements
When assembling stairs of any type, the following general rules should be observed:
- The number of steps in one march should not exceed 17 pcs. Their minimum number can be any. But usually stairs have at least 3 steps. The safest are marches with an odd number of them.quantity.
- The height of the stairs must be the same. Only the first one can be slightly higher than the others.
- The release of the stage is not allowed to be made too large. Otherwise, a person walking up the stairs can simply stumble. The regulations provide for a release length of no more than 30 mm.
- The distance from the top step to the front door must be at least 1 m. In any case, it is not allowed to make the platform narrower than the width of the front door.
Step design features
This main element of the stairs consists of two main parts:
- horizontal support treads;
- vertical risers.
The width of the first and the height of the second should be calculated as carefully as possible when drafting a project. It is on these two indicators that the convenience and safety of the march mainly depend. Sometimes stairs are made without risers. Such designs are cheaper, but they also look less thorough.
Step length
Stairs leading to a house or rooms, according to the SNiP standards, are supposed to be made quite wide. Standard steps, the dimensions of which are determined by GOST, have a length of at least 90 cm. But an indicator of 1-1.5 meters is considered the best option. On such a march, descending and ascending people will be able to disperse comfortably.
March Depth
The optimal width of the stairs leading to the living quarters is 30 cm. In any case, according to the regulations, this figure should not be less than25 cm (for the basement - 26 cm). That is, the width of the tread must be made such that the foot of an adult can fit freely on it.
The only exceptions to this rule are spiral and vertical stairs. The narrow side of the trapezoidal steps should be at least 10 cm wide. Vertical ladders, and especially side ladders, should be as mobile and light as possible. Therefore, the width of their steps is not regulated by the standards. Most often, this figure is 5-10 cm. In metal fire structures, steps can even be made from a thick rod with a diameter of 15-20 mm.
What should be the height?
When calculating this indicator, the angle of inclination of the march should be taken into account. GOST for the dimensions of the steps of a concrete staircase in multi-storey buildings, for example, provides for the following ratios:
- for structures with a slope of 1:2 - 125-145 mm;
- with a slope of 1:1.5 - 143 or 168 mm.
The last version of the stairs is usually used to descend to the basement or rise to the attic. The width of the tread in driveway concrete structures is always 30 cm. For basement and attic stairs - 26 cm.
In private houses, steps are usually made 150-200 mm high. It is this range that is allowed by the SNiP standards. The optimal height option depends mainly on the height of the people living in the house and the width of their step.
Step sizes: how to calculate optimal performance?
When drafting an external or internal staircase, the following formulas are usually used:
- A+B=450 mm (march reliability);
- B-A=120mm (safety).
"A" in this case - the height of the riser, "B" - the width of the tread. The ratios of the dimensions of the elements of an ideal march in terms of safety and reliability are calculated by the formula 2A + B=600 mm.
The dimensions of the stairs of the house depend, among other things, on the material used for its manufacture. So, for example, the standard board width is 75-275 mm with a gradation of 25 mm. For treads, both 250 mm and 275 mm material are suitable. Wider boards in this case are impractical to use. For risers, material is usually taken at 150, 175 or 200 mm. In this case, the second and last options are considered the most convenient.
In brick stairs, steps are most often 250 mm wide. Their height in most cases is 177-178 mm. Such dimensions of stair steps are determined by the dimensions of the material itself (length 250 mm, height 88 mm). When laying structures of this variety, they are usually made two bricks high. That is, 88 you just need to multiply by 2 and add 1-2 cm for the seams.
For the steps of metal and concrete stairs, the required parameters of length, width, etc. are determined only by the cost of the material and ease of use.
What else to consider?
The waythere should be standard and optimal sizes of steps, we found out. However, when drafting stairs, it is worth considering another important indicator. When choosing a material for wooden structures, you should pay attention to its thickness. Of course, too thin boards for stairs should not be taken. Otherwise, it will turn out to be unsafe and also short-lived.
The thickness of a wooden tread is determined by the ratio of 1:20 to its width. This provides a sufficient margin of safety. That is, a step board with a width of 250 mm must have a thickness of at least 12.5 mm. For the riser, you can use thinner material. A cut board a centimeter thick in this case is usually quite enough. Sometimes the vertical space between the steps is closed with just plywood.
Concrete stairs at the final stage are usually tiled. Therefore, when calculating the height and width of their steps, it is necessary to take into account the thickness of this material. For tiles, this figure is usually 4-9 mm. Natural stone tiles can have a much thicker thickness of 1-2 cm.
Conclusion
Subject to all the rules described above, in the house or in the yard, you can assemble the most convenient and durable staircase. Of course, correctly calculating the dimensions of the steps is only half the battle. When assembling the stairs, you should correctly choose the height of the railing (at least 90 cm), the methods of fastening the elements (for wood - only bolts), the angle of inclination, etc. However, it is the reliability of the steps that basically determinessafety and comfort of such structures. And this means that in this case it is not worth saving on material and going beyond the allowable indicators of length, width, height and thickness.
