Standard and optimal step sizes: GOST, features and recommendations

Internal and external staircases are available in almost every house. It is necessary to collect such constructions with preliminary drawing up of the project. When developing drawings, it is important to comply with all the standards stipulated by the SNiP and GOST. In particular, this applies to such an element of the ladder design as the steps. They must first of all be strong and reliable. To choose the sizes of steps of a ladder of a ladder march and an aperture follows so that to move on them it was convenient. In addition, their design should also be as safe as possible.

Types of stairs

In the courtyards and in the inner premises of the houses, lifting structures of the following varieties can be installed:

• Marching. This is the most common type of stairs. The steps are usually attached to them on a kosor or string. Marching stairs can be simple and pivotal. If it is impossible to equip the site due to a lack of free space, such designs are made curved using the stair steps.
• Screw. This option looks more modern than the march and takes much less space. You can install spiral staircases in any part of the house or yard, and not just against the wall. They usually have a round shape. The steps in these stairs are trapezoidal and are attached to the central pole. Sometimes rectangular spiral staircases are installed in houses and in courtyards. In this case, their construction includes two sites. Unfortunately, this option is cumbersome, and therefore it is used very rarely.
• Vertical. This type of staircase is usually used as a fireman, for lifting to unheated attics or descending into the cellar. Such staircases are simply two pillars, between which the crossbeams are packed. There are two main types of them: prefix and stationary. Often such stairs make folding.

Marching turning stairs are quarter (90 degrees) and half-turn (180 degrees). Screw constructions, in fact, are their variety. The rotation of these stairs is carried out on 180 gr. Next, let's see how in all these cases can be the size of the steps. GOST specifies precise indicators mainly for staircases of multi-storey buildings. In private, in most cases, optimal (but not exceeding the requirements of SNiP) width, length, depth and height are selected.

General requirements

When assembling stairs of any type, you should follow these general rules:

• The number of steps in one march should not exceed 17 pcs. The minimum number of them can be any. But usually in the stairs there are at least 3 steps. The safest are marches with an odd number of them.
• The height of the steps of the ladder should be the same. A little higher than the rest can only be the first.
• The release of a step too big to do is not allowed. Otherwise, a person walking down the stairs can simply stumble. The standards stipulate a release length of not more than 30 mm.
• The distance from the top step to the entrance door must be at least 1 m. In any case, it is not allowed to make a pad already the width of the entrance door.

Features of the design of steps

This main element of the ladder consists of two main parts:

• Horizontal abutments;
• Vertical risers.

The width of the first and the height of the second in the design of the project should be calculated as closely as possible. It is from these two indicators that the comfort and safety of the march depends largely. Sometimes stairs do without risings. Such constructions are cheaper, but they look less thoroughly.

Length of steps

The stairs leading to the house or to the 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 the best option is the indicator of 1-1.5 meters. On such a march, descending and ascending people can disperse with comfort.

Depth of the march

The optimal width of the stairs leading to the living quarters is 30 cm. In any case, according to the standards, this figure should not be less than 25 cm (for the basement - 26 cm). That is, the width of the tread is to be made such that the adult's foot can be placed freely on it.

An exception to this rule are only screw and vertical ladders. The narrow side of the trapezoidal steps should have a minimum width of 10 cm. Vertical ladders, and in particular the ladders, should be as mobile and light as possible. Therefore, the width of their steps is not regulated by regulations. Most often this figure is 5-10 cm. In metal fire constructions, steps can 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 must be taken into account. GOST on the sizes of steps of a ladder concrete in multi-storey buildings, for example, provides the following relations:

• For structures with a slope of 1: 2 - 125-145 mm;
• At a slope of 1: 1.5 - 143 or 168 mm.

The last version of the stairs is usually used to descend into the basement or climb to the attic. The width of the tread in the access concrete structures is always 30 cm. At the basement and attic stairs - 26 cm.

In private houses, steps are usually made at a height of 150-200 mm. It is this range that is allowed by the SNiP regulations. The optimal variant of height depends mainly on the growth of people living in the house and the width of their step.

Step sizes: how to make optimal calculations?

When drafting an external or internal ladder, the following formulas are usually used:

• A + B = 450 mm (reliability of the march);
• B-A = 120 mm (safety).

"A" in this case - the height of the riser, "B" - the width of the tread. The ratio of the dimensions of the ideal elements for safety and reliability of the march is calculated by the formula 2A + B = 600 mm.

The dimensions of the stairs of the house depend, in particular, on the material used for its manufacture. So, for example, the standard width of the board 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 is not practical. For risers usually take material at 150, 175 or 200 mm. In this case, the most convenient are the second and last options.

In brick staircases, the steps most often have a width of 250 mm. Their height in this case in most cases is 177-178 mm. Such dimensions of ladder steps are determined by the dimensions of the material itself (length 250 mm, height 88 mm). When laying designs of this variety, they are usually made two blocks high. That is, 88 simply multiply by 2 and add 1-2 cm to the seams.

For steps of metal and concrete ladders, the necessary parameters for length, width, etc. are determined only by the material cost and convenience in use.

What else should I consider?

What we should be standard and optimal sizes of stages, we found out. However, when drafting a ladder, one more important indicator should be taken into account. When choosing the material for wooden structures, it is worth paying attention to its thickness. Of course, too thin boards for the stairs should not be taken. Otherwise, it will turn out to be unsafe and also short-lived.

The thickness of the wooden tread is determined by the ratio 1:20 to its width. This provides an adequate margin of safety. That is, a board of a 250 mm wide should have a thickness of at least 12.5 mm. For the riser, the material can be thinner. Cutting boards with a thickness of a centimeter in this case are usually quite enough. Sometimes the vertical space between the steps is covered and simply plywood.

Concrete stairs at the final stage are usually tiled. Therefore, when calculating the height and width of their steps, one must also take into account the thickness of this material. At tile this indicator usually makes 4-9 mm. Tiles made of natural stone can have a much larger thickness of 1-2 cm.

Conclusion

Subject to compliance with all the above standards, in the house or in the yard you can collect the most convenient and durable ladder. Of course, it is only half the battle to correctly calculate the size of the steps. When assembling the stairs, you should correctly choose the height of the handrail (at least 90 cm), the ways of fixing the elements (for the tree - only the bolts), the angle of inclination, etc. However, it is the reliability of the steps that determines the safety and comfort of such structures. And this means that it is not worthwhile to economize on the material and go beyond the permissible parameters of length, width, height and thickness.