For some reason, the overwhelming majority of informational materials about stairs tell not so much about the functionality of products, but about their original design. One gets the impression that the “semantic load” of an element, like a staircase, does not deserve attention.
But actually it is not. A staircase is, first of all, a structure that performs a very specific and definite function. Therefore, in this article we will consider various types of stairs precisely from the point of view of their functional performance..
All the variety of stairs existing in the world can be divided into two groups: interfloor stairs and stairs for special purposes. General purpose staircases are used most often, moreover, when we say “staircase”, we mean a structure that connects the floors. The owner has to use the interfloor staircase more than once a day, so the main criterion for evaluating their design should be ease of use. Ease of use consists of a combination of several categories: the ascent / descent angle, the width of the passage along the stairs, the presence of turning sections, the presence of free space above the head of the climbing person, safe fencing of stairs and stairways.
Of course, the ease of use, first of all, depends on the angle of the stairs. The most convenient ascent / descent angles are in the range from 30 degrees to 40 degrees. The steepness of the rise is directly related to the ratio of two quantities – the height of the step (riser) and the width of the step (step). The steeper the staircase, the less space it needs to install in the house. At the same time, the more comfortable the ladder (more positioned), the more space must be provided for it. Accordingly, any owner has to choose between convenience, safety and precious square meters..
However, when making a choice in favor of square meters, it should be remembered that having gone beyond certain parameters of convenience (30-40 degrees), you already get options for special stairs. If the angle is less than 20 degrees, the staircase goes into the category of ramps, if more than 45 degrees – into the category of attached (folding).
It is important to take into account the fact that the most difficult action with a steepness of more than 40 degrees is going down the stairs..
At angles over 45 degrees, descent can only be done backwards. Of course, such a ladder cannot be considered convenient for constant daily use. The standard for a staircase in a house (apartment) where one family lives is 100 cm or more. A staircase can have a width of 80 cm, provided that its configuration is simple, it is built along one wall and allows you to lift any large objects. Less than 80 cm can be auxiliary stairs that are not the main ones, for example, stairs to the basement or to the attic.
In order for the staircase to become an architectural dominant, it made it possible to climb with maximum comfort – it should be made at least 120 cm.and with the right choice of design solution, it will become a real decoration of the house.
All stairs, except for straight ones, have turning sections, and spiral ones consist only of them. Implementing a rotation is not a big problem, but it should be executed correctly. The easiest way to turn is through the platform, which is not always possible in cramped conditions, since the platform is one ascent (step) up, and in rooms of limited dimensions, the rise in height should be carried out as often as possible so that the ascent angle is most convenient.
Turning through winder (triangular) steps is more common in small rooms and private houses. In this case, the optimal number of them is 3 angular steps per one turn of 90 degrees. In plan, they should create a square or rectangle. The number of winder steps is more than 3 possible, but it must be borne in mind that the walking area is reduced in this case, since narrow sections of winder steps cannot be used.
When calculating a staircase located between floors, it is very important to take into account that the opening in the ceiling above the staircase must correspond to a safe passage along the entire rise. The distance between the step and the ceiling should not be less than 200 cm.Although a person with a height of 180 cm easily walks along a passage with a height of 185 cm, he will instinctively tilt his head and experience discomfort from this.
Fencing stairs and openings with handrails (balusters, posts and handrails) is a necessary component of overall safety. The recommended height of the fence is 90 cm, with a ladder height of more than 6 m – 110 cm.
The distance between the balusters should be at least 15 cm in the centers. The thickness of the balusters does not play a decisive role, but the rigidity of the entire structure of the fence should be very high. This can be achieved by correctly tying the handrails to the posts and securely attaching the posts to the base..
Pillars must be installed at all turns, and if the length of the fence in a straight line exceeds 3 meters, additional support pillars must also be installed.
Special purpose ladders
Special ladders are not only stepladders, as we used to think. They are not similar to each other, but at the same time they are stairs, since, firstly, they allow the function of ascent and descent, and secondly, they have two guides and a certain number of cross-beams between them, serving as steps. These are ladders of a wide variety of purposes, which fulfill their function – lifting “as needed”.
Of course, stepladders are the most famous of the soft helpers that are found in almost every house that has undergone repair and construction.
The division of such stairs into household and professional ones is mainly determined using several criteria..
Lifting height – household ladders, ladders allow you to climb to a height of 2 to 4 meters, professional, sliding structures are much longer, more stable and are limited in height only for safety reasons.
Maximum step load – the greater the possible maximum step load, the closer it is to the professional class. Households are usually limited to 100-120 kg; The presence of several functions – the simplest household ladder – the step-ladder serves only as a ladder. Professional – they are also used as scaffolding, goats, having reliable fixation methods in different positions and at different heights.
The simplest ladders should be chosen, paying attention to the reliability of the connections of all nodes, fixings, the presence of non-slip steps. When unfolded, the staircase must have a geometrically correct configuration. This is determined visually – when looking at a ladder standing on a flat surface of the floor, you should see that the legs of the ladder adhere evenly to the floor and have no gaps, which can be revealed by additional checking by swinging the ladder to the sides. Ladder legs must have non-slip and non-scratching floor pads.
For household purposes, the most reliable and convenient option is a universal staircase with steps on both sides. This will allow you to use it when working together, which, as you know, is often necessary..
For professionals, they produce ladders that transform into scaffolding, ladders that can vertically move apart and turn into telescopic attachments. This type of mobile ladder has a lot of models and is presented extremely widely. However, it should be noted that products of well-known companies should be chosen, this significantly reduces the risk of a fall and the following consequences..
Usually ladders are made, as a rule, of metal and wood. The bearing racks are made of iron or steel pipes, and the steps are wooden. Of course, these structures do not differ in special grace, they are awkward, heavy and even when folded take up a lot of space..
Understandably, wooden ladders are impractical. Over time, the tree dries up, cracks, looses in the places where the steps are attached to the posts and does not withstand loads over 100 kg. In addition, a wooden stepladder of 5-6 steps is a rather heavy thing..
Therefore, the best material for stepladders was and remains metal: aluminum and duralumin. In principle, duralumin (or otherwise duralumin) is the same alloy. But manufacturers of ladders claim that these are still different things: they say, the percentage of aluminum in duralumin is lower. Therefore, aluminum ladders are stronger and more expensive than duralumin ones. But both aluminum and duralumin are durable and reliable materials. Stepladders are often made of composite materials. For example, the racks are made of metal, and the steps are made of plastic or wood. Please note that the main load falls on the racks. Therefore, when choosing a stepladder in the store, do not hesitate to squeeze them harder with your hand. If you feel that the rack is “walking”, it is better not to buy, then you will not be sinned.
In most cases, metal steps from both sides are riveted to metal posts. And the metal cut is covered with plastic. As it turned out, this piece of colored plastic plays not only a decorative role, but also serves as an identification mark. It turns out that the color can be used to determine the country of origin of the ladder. If the step-ladder has red inserts, then it was made in Germany, with blue ones – in Italy. If the color is orange, it is most likely Finland or Holland..
The most reliable fastening is the method when the steps are rolled into a rack. That is, both ends of the step (metal plates or pipes) are pressed into the posts. The metal is tightly “soldered” into the metal. Such steps will never jump out, and it is impossible to break them..
The steps should be grooved, that is, with transverse stripes embossed in the metal, and even better with plastic or rubber mats. Why this is important is understandable – so that the foot does not slip.
However, not only our feet should not slip, but also the legs of the ladder itself. Therefore, it is desirable that they be “shod” with rubber or soft plastic tips. Another hazard is to use a ladder without restraining straps. Most often it happens like this: you put up a step-ladder and fix it with the top step or platform that connects both sections of the step-ladder. Everything seems to be in order, you can climb up. But suppose you poorly secured the site, and the ladder began to creep apart at the most crucial moment. So, it is the restraining belts that will not let her collapse completely.
Mansard stairs are used to save living space. For example, if you store some items of non-daily use (seasonal clothing, sports equipment, archives, etc.) in the attic, then it is impractical to have a permanently installed ladder. It is much more practical to use a folding.
The main function of attic or, as I call them otherwise, attic stairs is to emerge from the ceiling only when necessary, which leads to additional useful qualities of these models. Firstly, the folding mansard ladder saves a lot of free space, and, secondly, it prevents (when folded) heat leakage into the attic, which would occur if a non-transforming ladder was used, for example, an attached.
Modern designs of mansard stairs (lever, pincer, telescopic) allow even an unprepared user to control the folding-folding process. Design options provide price options. A simple wooden staircase at a price of 3,000 to 6,000 rubles is available to most developers. More expensive metal stairs also have different prices, due to the varying degrees of complexity of their mechanisms.
A three-knee (lever) ladder consists of three knees, which, when unfolded with the help of a spring mechanism, form a ladder. The folding-unfolding mechanism is operated with little effort. In order to “cause” the ladder down, you need to pull it by the cord or ring installed on the hatch cover. To send it back, folding two knees, give the direction of movement with a slight push, which completes the spring mechanism. When folded, the staircase is not visible – only its cover is visible, which can be painted in the color of the ceiling.
Ladders of this type are always sold ready-to-install, packed and with detailed instructions for on-site installation and further operation attached. They are made, depending on the model, of wood or aluminum alloy. The desired height is set by adjusting the last (lower) knee. The cost of such products varies, depending on the design, from 120 to 550 dollars..
The claw-shaped ladder is designed as a multi-link mechanism that can be folded out by successive stretching of the ladder to the working condition. It is also powered by a spring-loaded device that allows both folding and unfolding. Unlike three-knee ladders, it is made only of metal (aluminum alloy).
The ladder is fixed in the working position using a spring stop that does not allow the ladder to fold spontaneously. As with any mechanism, all folding ladders require extra attention during use. The spring mechanism, with inattentive handling, is able to remind of itself quite strongly.
It is also not recommended to carry out experiments on descent from the upper floor with a closed (inoperative) staircase, unless provided by the instructions. All detailed instructions are included with each ladder unless you buy them from random locations.
The cost of a pincer ladder ranges from $ 600-800.
Of all the folding mansard stairs, only telescopic can be recommended for use not only for a private home, as the most durable and adjustable. The settings of this design are the most mobile: the user has the opportunity to adjust the lifting and lowering height as accurately as possible while maintaining the ability to change it many times. The absence of linkage also increases the operational loads on the ladder. The required height level is fixed using a locking mechanism. On some models of telescopic ladders, there is an adjustment of the tilt levels and the height of the steps.
At the end of the story about attic stairs, we note that all products, with the seeming simplicity of the design, are made on the basis of precise engineering calculations, taking into account the distribution of loads, the force of the spring mechanism and various operating conditions, so buying products from random manufacturers is unsafe for the health of you and your loved ones.