Cantilever staircase in a wooden house design. Cantilever stairs: properties and manufacturing method. Damage to cladding, potholes, breaks

Cantilever stairs are unique functional elements of the interior that can give it lightness and modern look, while maintaining free space in the room. Main feature any such staircase lies not only in the configuration itself, but also specific type fastening steps that do not have obvious support. They lack traditional variations of stringers or hybrid vertical supports typical screw structures. The cantilever steps of the staircase are open on all sides. They seem to float in the air, as the steps come out of the wall.

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A feeling of lightness is created by attaching only one part of the steps to hidden supports, and wall-mounted handrails are used as handrails. This is why the cantilever stairs in the photo may seem unsafe. However, the correct design of such a structure completely eliminates the risk of its destruction, ensuring the safety of each family member.

In general, cantilever stairs, unlike traditional structures, have the following advantages:

occupy a minimum of space, so they do not clutter up the visiting space;
do not block light and air flows in the room;
have a stylish attractive appearance, having the opportunity to enter as a highlight of any living room;
They have an acceptable cost, which is realized due to the small amount of materials for their production.

But, like any other interior items, cantilever stairs have not only positive, but also some negative qualities:

require the most durable fastenings;
difficult to design and install;
less safe than traditional stairs due to the lack of double-sided railings (at the customer’s request, railings can be installed on the free side of the steps).

However, with a professional approach, all these disadvantages can be leveled out, which makes cantilever staircases suitable for any cottages and two-level apartments.

Manufacturing of cantilever stairs

For the purpose of producing cantilever staircases, today the most various materials, among which.

Metal. Such designs are not particularly popular because, due to the characteristics of the material, they are quite difficult to fit into the most common interior styles. However, console metal staircase may become great solution for interior in high-tech or loft style.
MDF and wood. These are the most common materials for the manufacture of steps of cantilever stairs, which is primarily due to the universal interior qualities of the materials. A cantilever staircase made of wood will fit perfectly into any interior.
Plastic. Only the most durable types of plastic can be used. But most often it is used only for finishing the treads of steps.
Glass. Tempered glass is a fairly popular material for making steps of cantilever stairs. Such structures look almost weightless, but require additional strengthening.
Concrete. A cantilever concrete staircase is quite complex in design and execution, since it requires reinforcement of each individual element.

In addition to the directly visible one, any cantilever staircase also has a part of the structure hidden from view, which ensures it reliable fixation. This item The structure is made of metal in the form of channels and brackets, as well as anchor bolts.

There are several basic ways to attach cantilever stairs. Among them:

Wall. The steps cut directly into the wall to a depth of up to 40 centimeters, which depends on the material of the stairs.
Kosour. A staircase on a metal stringer has the appearance of a complex welded structure and, as a rule, is used in cases where the steps cannot be cut into the wall. Also, such structures can be found under the name of a cantilever staircase on a side stringer.
Bolts that connect the free part of the treads, thereby transferring the load to each subsequent element until they are fixed to the floor or ceiling.
Cables acting as additional support, at the same time replacing handrails. In this case, the load from the free side of the steps is transferred to the ceiling.
Profile. Enough reliable option cantilever staircase designs having common features with a stringer. In this case, the steps are fixed to the profile, which is then covered with finishing materials.

As for the cost, the price of a cantilever staircase depends on a number of factors, including production materials and type of fastening, as well as the height of the structure and other conditions.

When the need for comfortable and safe access to the second floor is thought about even in the process of designing a house, any type of staircase can be laid. This is much more effective than trying to squeeze in at least something digestible, not to mention aesthetics. One of the participants in our portal thought through everything in advance, and as a result he has a cantilever staircase, which is considered one of the most attractive in terms of “airiness”. His experience is interesting because, having remained a customer, he was still able to save a lot even in terms of finances, not to mention time and labor costs.

About cantilever stairs.
sergpn.
Project.
Materials and tools.
Execution.

About cantilever stairs

The effect of lightness and airiness in these structures is achieved due to the absence of external supports in the usual sense - there is no even stringer, no bowstring, no vertical support. “Floating” steps are mounted directly into the wall, taking into account that the entire load will fall only on this fastener. When choosing this type of staircase, it is necessary to correctly calculate, first of all, bearing capacity walls. The type of fastening of the steps depends on the result of the calculations; these can be the following options:

insert into the wall - the depth depends on the strength of the wall, on average 20-40 cm;
brackets - how special fasteners, and various variations (metal plates, channel, decorative supports);
frame - with a minimum load-bearing capacity of the wall, a metal frame (channel, profile) is placed close to it, which is fixed to the floors, and cantilever steps are attached to it.

The handrail usually runs along the wall; if necessary, ceiling cords are used as a fence; in rare cases, for the sake of the visual component, both strands and a handrail are dispensed with.

As for materials, the flight of imagination is almost limitless, but the most practical stairs are those with steps on a metal frame with wooden overlays or cases. This is exactly the version our craftsman has.

Cantilever metal staircase from sergpn

sergpn

Project

Topikstarter’s house was built using monolithic technology, and since he initially conceived a cantilever staircase, one of the metal frame’s rigidity diaphragms was used for the structure. The missing fragment was supplemented with a channel.

All calculations and the project itself sergpn ordered from professionals. Both load-bearing capacity and resistance to dynamic loads are taken into account. Our craftsman believes that the project is mandatory.

sergpn

All points were taken into account at the design stage, I deliberately highlighted the cost of calculation as a separate line, and did not write that “we go to the barn, look at what scrap metal is left, and make a ladder out of it in approximately this shape.” Considering the pathological aversion of the majority of forum members to any expenses for designers and the desire to build according to intuition, I want to convey to them that the design and calculation are savings, not expenses.

Drawings of your staircase sergpn posted for everyone interested.

Materials and tools

Materials used:

profile pipe 60×60×5 mm – frame of steps;
sheet metal, 10 mm thick – support plates and “kerchiefs”;
sheet metal, 4 mm thick – cover and end strips;
channel 270×6 mm – the missing part of the support for four steps;
chemical anchors, studs - for attaching support plates and channels to the wall.

Instead of bothering with cutting such thick metal with a grinder, I gave everything to a workshop for plasma cutting, an inverter welder and professional welders of the 5th category were used for welding.

Execution

The first stage of marking was to drill holes for the studs and fix them in the wall; the next step was to install the support plates for the steps and the channel on them. The craftsman preferred chemical anchors to conventional ones in order to avoid the formation of backlash in the future.

Due to certain difficulties, the algorithm for executing the steps turned out to be as follows:

pipes are “tacked” to the support plate;
headscarves;
cover sheet;
end strip.

This sequence is due to the fact that with other options it was not possible to maintain an ideal plane.

sergpn

They cooked it one at a time, which was somewhat more difficult, due to the impossibility of attaching the thrust plates evenly (in some places there was reinforcement, in others there was some kind of nuisance). Therefore, each step is done individually. It is easier to weld a frame made of corrugated pipe, but this design works worse in bending than parallel pipes completely sewn on top with a covering plate. But, on the other hand, sewing a sheet on top is possible (as practice has shown) only for pipes that are already welded to the plate, otherwise it is difficult to maintain parallelism (the sheet leads). This is, in fact, why this assembly method was chosen.

Some participants in the topic were interested in the question of whether it would be easier to use through fasteners. As the craftsman answered, due to the load, it is impossible to make the bolts flush. But doing double the work of attaching the plates on the other side and then figuring out how to close them is too problematic. Others were confused by the scarves, since there are many examples of installing steps without this unit. It turned out that scarves are not only necessary, but also useful.

Since, for financial reasons, decorative wooden cases are not expected in the foreseeable future, the craftsman generously treated the finished structure with primer and stopped there for now.

As recommended by the project, after completion installation work The staircase was checked for load-bearing capacity using the “classical” method - 250 kg of cement bags were loaded onto the steps. The deflection was less than 1 mm, which is quite satisfactory, considering that the weight of the household is much less, and no one plans to jump on consoles.

Taking into account all expenses, the staircase cost 45 thousand rubles:

project – 5 thousand;
metal (with cutting) – 15 thousand;
installation (welding/cutting on site) – 20 thousand;
consumables and components (anchors, studs, electrodes, primer) – 5 thousand.

It took only four days to make the staircase. As he separately emphasizes sergpn, companies offering ready-made designs such a plan, they called a price tag of 100 thousand rubles and a period of two weeks. Therefore, even if you refuse self-made in favor of a professional one, you can actually cut costs in half. If you have the appropriate skills and equipment, then the costs of materials are minimal in our times.

You can follow further developments of events, read more about different types staircases, including cantilever ones - in the article how to provide access to the stairs yourself cold attic- in the material. An example of a very unusual staircase is in one of our videos.

Are cantilever staircase structures as convenient as they sometimes want us to believe? In order to understand this issue, you must first understand what cantilever stairs are: the features of their structure. This staircase is considered the most effective among many other one-story staircases. The structure itself is not large, and the steps seem to “float” in the air.

Application

Today, during the construction or improvement of a home, there is a struggle for every square meter free space. Having opted for a concrete or wooden staircase on stringers, you can immediately say goodbye to a fairly decent part of the free space, as can be seen in the photo. But there are a number of light and transparent stairs that not only will not take up much space, but will also be an excellent design solution, fitting perfectly into the interior of the room.

The cantilever staircase option is most suitable for connoisseurs of minimalism and lovers of high-tech style. Nothing superfluous - this is how this species can be briefly described. These are ordinary steps, attached on one side to a wall or any other support. Of course, you can’t do without a fence, but it can be almost invisible, but at the same time responsible for safety.

Terminology

For those who are not strong in construction, here are some frequently used terms that will help you better understand this article:

Baluster – posts intended to support railings;
The console is a tightly fitted shelf system;
Kosour – load-bearing structure, used for fastening steps;
Railing - staircase fence;

A riser is a plank fixed vertically that covers the space under the step. Equal to height steps;
Handrail - part of the railing necessary for the convenience of ascending or descending steps;
Prokid - a fencing zone located parallel to the march;
Tread – a horizontal element of a step;
Post - the outermost post of the railing resting on the ceiling;
Bowstring - an inclined structure that supports steps attached to it at the ends;
Tie rod - a cable necessary for fastening steps to the upper floor.

Cantilever staircases are not provided when assembled. They are made to individual orders. But catalog models often serve as the basis. In this case, it is advisable to make a minimum of changes so that replacement of factory components is not required. Although decent companies, both in Europe and in Russia, replace components exclusively with factory ones.

Making a support

Those who encounter a cantilever staircase for the first time will be a little surprised by its appearance and may even be afraid to climb it. But its structure has a completely engineering explanation, and its construction is a painstaking and complex process, as shown in the video. The first thing that is laid in the process of constructing a staircase is a supporting structure for the steps, which can withstand a load of 150 kg, without taking into account the weight of the railings. Moreover, this weight is calculated for the extreme point of the suspended step.

Installation

It is very important to know what the wall is made of, to which the steps of the cantilever staircase will later be attached. It's best if it's brickwork, or other heavy materials. This is necessary because it is in the wall that the ends of the steps are installed with your own hands, buried at least 20 cm with a flight width of 80 cm. The size of the recess must be increased to 30-40 cm if the wall consists of expanded clay concrete blocks or slotted bricks, as seen in the photo.

Style trends in interior design are increasingly influencing the modification staircase structures. Thus, cantilever stairs are gaining popularity. Its advantage is that it does not interfere with the spread of light indoors. This design looks quite non-standard, one might even say bizarre. The treads simply hang in the air on consoles lowered from the ceiling. But you shouldn’t be afraid to walk on it, because the design is well thought out. If you have construction experience and desire, you can make a comfortable and unusual cantilever staircase with your own hands.

Design features

Design advantages:

unusual appearance;
low material consumption - such stairs do not have risers, and sometimes even railings;
space saving.

It is important when designing such a structure to take into account the loads perceived by the tread. They must withstand 150 kg. – and this figure does not take into account the weight of the handrails.

Even organizations engaged in the manufacture of cantilever staircases do not have products ready for installation. They have only individual elements from which the march will later be assembled. Each design must be developed individually for the customer, taking into account all conditions.

But making such a staircase is quite difficult. Its installation takes place during the construction stage or before finishing the premises. There are several ways to attach treads:

Embedding steps into the wall.
Embedding brackets into the enclosing structure, onto which treads will subsequently be attached.
Fastening steps using anchors.
Ceiling mount.
Brackets that are welded or screwed to a steel bowstring.

If the house is made of brick or heavy blocks, good option To install a cantilever staircase, the steps will be sealed during the construction stage. To do this, the ends of the treads must be embedded in the wall at a distance of 1/4 of finished product. So, if you want to make a flight of stairs equal to 80 cm, then you need to lay 20 cm steps. Another requirement for this installation option is that the tread must be pressed down with at least ten rows of masonry.

In case of using lighter building materials, such as porous ceramic, hollow expanded clay concrete blocks or slotted brick, the depth of laying the treads increases by 1.5-2 times and will be 30-40 cm. This will be difficult to implement if the thickness of the designed wall is less than required.

Aerated concrete buildings also have their own design features for cantilever staircases. In the walls, it will be necessary to strengthen the places where all treads are sealed using embedded elements made of heavy concrete. There is no need to worry about your appearance, because there are decorative overlays, for example, wooden. Laminated panels, natural or artificial stone are also suitable. When using this design in a loft style solution, you can leave everything unchanged.

With this option for installing a cantilever staircase, it is necessary to wall up a profile pipe no more than a meter long into the wall. The depth of the bookmark should be at least 25-30 centimeters. The remaining outlets should correspond to 2/3 of the tread length. The requirements for the walls remain the same, and the possibility of choosing the material for the steps has expanded. For this fastening option, you can use engineered solid wood, as well as materials based on wood composite, such as chipboard, MOR. This happens because the treads no longer act as self-supporting structures. The entire load is transferred to the brackets embedded in the wall. Metal parts can be hidden in grooves or holes that are drilled into the treads.

Fastening with anchors

This method is used when the walls have already been erected and it is not possible to embed fasteners into the finished enclosing structure, as in the first two cases. But it also remains important material. Walls made of porous block or slotted brick are unable to hold anchors.

To reduce the possibility of anchors being pulled out if the walls are not made of sufficiently strong material, it is necessary to significantly increase the size support platforms.

In order to carry out such an installation of a cantilever staircase, you will need welded brackets with support platforms. The finished elements must be attached to the wall at the location of the steps using anchor bolts. Their number must be at least four, and their length must be from 15 cm, while the radius must be chosen more than 10 cm.

Ceiling mount

This method will be an alternative for those whose house has already been built or whose boundary walls are not strong enough to withstand the loads. The steps must be secured before starting finishing works. To briefly describe the essence of this method, it consists in using a powerful welded metal frame made of a channel; a profile pipe is also suitable. This design spans the entire height of the room, because how to attach metal frame will be towards the ceiling.

The metal frame is placed along the entire length of the flight close to the wall. It also needs to be tied to the upper and lower floors. After this, it is necessary to weld the cantilever supports for the treads to the resulting racks; it is possible to use fastening bolts. The resulting frame can be hidden with plasterboard sheathing or masonry made of light blocks.

Steel bowstring

This method of installing a cantilever staircase is perhaps the most difficult.. It uses brackets that are welded or screwed to a steel bowstring. This is the only support. It must be secured to the floors using powerful support platforms and anchors. To prevent the bowstring from twisting under load, it is necessary to create complex design. It will have welded trusses with stiffening ribs, which are located transversely, diagonally and longitudinally. This design is a bit like the booms of a tower crane. You will also have to work hard with the console. It needs to be thought through to avoid the unsteadiness of the steps, provided that it is not embedded in the wall.

Strengthening the structure

If you doubt the safety of operation and reliability of your cantilever staircase, you can use some engineering tricks to strengthen the structure:

Rigid connection of treads to each other. Loaches are suitable for this. They will transfer the loads to the floor. Bolts are hidden bolts that are used with a spacer sleeve. If we talk about the cantilever structure, then it is necessary to connect each pair of treads using one such bolt, placing it at the hanging edge. Since all the main loads fall on the wall mount, it becomes possible to use bolts small size. This option for strengthening the structure will make it possible to reduce the brackets. So, for each stage it will be sufficient to use one pair of rods that will have following parameters: length – 40-60 cm, diameter – 3-4 cm, embedding in the wall – 8-16 cm.

Bolts can be hidden by disguising them as parts of the enclosing structure, and also hidden in the inside of the riser.

Mounting to the ceiling using ties. For this work you will need cables, the material for which is stainless steel 8-10 mm thick. You will also need to install screw hooks - a lanyard. They will help eliminate slackness of the cords. This type of hanging fastening will make the structure airy, unlike bolt-on.

Possible errors

When installing a cantilever staircase, there is a possibility of missing some features of its structure, which will lead to danger of use. The most common mistakes are:

Incorrectly chosen method of attachment to the enclosing structure. For example, it would be a mistake to try to tie it to the masonry using anchors if the wall is made of slotted bricks or light blocks.
Unreliable fastening of brackets to the wall. At wrong choice diameter of the steel anchor or if used plastic dowel instead, loosening of the treads may occur.
Using insufficiently thick metal as a bracket or frame. Selecting an element diameter of less than 3 mm. can lead to twisting of load-bearing elements under load.
Installation of treads on brackets in the wall without using a special damping gasket. Its use will prevent the transmission of footstep sounds through the building envelope to adjacent rooms.
Use of fairly heavy material for railings. It is worth abandoning cast or forged fencing, because it will place additional stress on the steps.

Perhaps this representative of the family of interfloor stairs is the most spectacular. Sometimes it seems that its steps are floating in the air. But this is only an illusion; in fact, this is a carefully thought-out engineering design.

Traditional wooden staircase on bowstrings or stringers, with its massive pillars, obligatory risers, turned balusters and wide handrails, creates a feeling of solidity, but at the same time blocks the light flux and limits the field of view. In other words, it requires a lot of free space. Modern interior styles do not tolerate such extravagance: designs should be light and transparent, lines should be simple and sweeping.

1. The main support of this unusual staircase cantilever brackets, auxiliary support, ceiling ties. The design has retained its visual lightness, despite the fact that its steps are quite massive, and thanks to the handrail running along the wall and the rope fence, it is very convenient and safe to move along it.
2-4. The cantilever principle is widely used in the manufacture spiral staircases. The assembly of their attachment to the pole can be made in such a way that the step does not require any additional support. The pillar will have to be made more massive, but then neither a bowstring nor a stringer will be required.

5. Typically, the steps are strung on a central pillar, installed spaced between the floors, and clamped using spacer bushings.
6. Bolts and miniature wall brackets are used to add rigidity to the structure.
7, 8. Multilayer fencing tempered glass(7) has a significant mass, so it is almost never supported on steps, but attached to the floors. Such railings can become additional support for the march, and the main load is taken by steel brackets attached with anchors to the wall (8).

In response to requests from designers, new types of staircases appeared: cantilever, suspended (on ties), bolted, spinal (on a central stringer) and combined. Probably, the dream of fans of minimalism and high-tech style is fully embodied by console models, in which there are no unnecessary parts, only steps, and attached to a support (wall, pillar, column) with only one end, while the other is free." floats" in the air. They try to make the fencing of such stairs as inconspicuous as possible, and in radical versions they do without railings at all. But it should still be noted that such extremes are rare and are intended more for demonstration than for practical application. And the console steps themselves pure form You don’t see it often, usually this mount is combined with other support units.

As a rule, cantilever stairs are not sold ready-made; they are made to size specific premises and taking into account the requirements of the home owner. When fulfilling such orders, European companies take one of their catalog models as a basis and use factory components, making a minimum of changes to the design (thanks to this, their products are of consistently high quality). Domestic firms produce mainly piece goods.

Looking for a foothold

Building a cantilever staircase is a complex and time-consuming task. Its foundation must be laid at the stage of erecting the walls of the building (or at least before interior decoration), because each step must withstand a load of at least 150 kgf applied to its suspended, that is, not supported by anything end (and this is in addition to the weight of the railing!). Such high strength can be achieved in different ways.

Sealing the steps. During the construction of the wall, the ends of the steps are embedded into it to a length of at least 200 mm (with a maximum flight width of 800 mm). This is only feasible if the masonry is made of bricks or fairly heavy (for example, solid expanded clay concrete) blocks, and it is necessary that each step be pressed down by at least ten rows of masonry. When using porous ceramic and hollow expanded clay concrete blocks, as well as slotted bricks, the depth of embedding must be increased to 300-400 mm, which is not always possible with the thickness of the wall. When building with aerated concrete, it will be necessary to strengthen the embedding site of each step with embedded elements made of heavy concrete. Not just any steps are suitable either, but only those made of very hard and elastic materials, such as reinforced concrete. However, they are quite easy to decorate with the help of wood overlays, laminated panels, natural or artificial stone. Or you can leave the steps in their original form - you can’t find anything better for a loft-style interior.

Sealing the brackets. Sections of profile pipe up to 1 m long are embedded into the wall to a depth of 250-300 mm, leaving outlets equal to approximately 2/3 of the length of the step. At the same time, the requirements for the wall are not reduced at all, but the steps can be made of engineered solid wood, as well as materials based on wood composite (chipboard, MDF). The fact is that in this design they are no longer self-supporting, but are supported by steel brackets. Metal parts are usually hidden in grooves or holes milled (drilled) in the steps. Please note that to implement projects with pinched and embedded consoles, you should contact only leading construction companies, and architectural supervision is a prerequisite for success.

Fastening with anchors. The method is applicable after completion of the main construction, but will require welded brackets with support platforms. Each such element is secured to the wall with four or more anchor bolts with a length of at least 150 mm and a diameter of 10 mm. The requirements for the material of the enclosing structure in this case are very strict: neither a porous block nor a slotted brick will hold the anchors (or, in order to reduce the force of pulling out, the supporting platforms will have to be greatly increased).

9. The creation of more and more original architectural forms is becoming increasingly important for manufacturing companies in a great way demonstrate the skills of your engineers.
10-12. High-tech style corresponds to products made of aluminum, glass and plain laminated panels (10, 12). Solid wood steps with chrome railings emphasize the eclecticism of the interior (11).

13, 14. When making fencing according to individual order You can give free rein to your imagination, for example, decorate pillars and balusters with inserts made of copper, brass, bronze or cut glass. It is only important not to overload the supporting units and not to disrupt the stylistic unity of the interior.
15. Glass steps always require bolt support, since they only allow the use of short wall brackets.
16. Only the most experienced specialists undertake the design and construction of reinforced concrete stairs.

Don't depend on the walls

If the wall does not have the necessary strength, this is a serious obstacle to the construction of a cantilever staircase. But still surmountable. Let us describe a method for attaching steps, which can be implemented in almost any building before finishing work begins. Its essence is the use of a powerful welded metal frame made from a channel or profile pipe. The structure is made up to the ceiling, the entire length of the flight, placed close to the wall and tied to the upper and lower ceilings. Cantilever supports for the steps are welded (or bolted) to the racks. The frame is then hidden using plasterboard sheathing or lightweight block masonry.

The most complex type of cantilever staircase with brackets welded (screwed) to a single steel string, which is attached to the floors using powerful support platforms and anchors. To prevent the bowstring from twisting under load, it itself must be a complex welded truss with longitudinal, transverse and diagonal stiffeners (like a tower crane boom). And yet, even a well-thought-out and well-made console (except for one embedded in the wall) does not allow you to completely get rid of the unsteadiness of the steps. The staircase, first of all, should be safe and comfortable, but what kind of comfort can we talk about if you feel deflections and backlashes at every step? We have to look for ways to strengthen the structure.

Console help

The engineers' task is to create a not too noticeable, but sufficiently reliable support for the second end of the steps. For example, you can rigidly connect all the treads to each other using bolts and thus transfer the load to the floors. Bolts are hidden bolts used in conjunction with spacer bushings. In the case of cantilever design each pair of steps is connected with just one such bolt (and not two, like a typical bolt), located at the hanging edge. Since the main load is borne by wall mount, the bolts can be made miniature and disguised as fencing parts or hidden inside risers. On the other hand, the use of bolts makes it possible to significantly simplify and reduce the brackets: for each step, a pair of rods with a diameter of 30-40 mm and a length of 400-600 mm, embedded in the wall at 80-160 mm, is quite sufficient.

Fastening steps to the ceiling with ties is no more difficult than a bolt connection. You just need to purchase cables from stainless steel 8-10 mm thick and install screw hooks, allowing you to select the slack of the cords and lanyards. Stairs with hanging mount they look even more airy than bolts.

The editors would like to thank the companies "White Maple", "SM Kvadrat", Euroscala, UNION
for assistance in preparing the material.