If you are a resident of one of the historical cities of Russia, then you are surrounded by familiar facades of old brick buildings every day. Their openwork, carved plastic gives a special flavor to each city separately, while making them somewhat similar to each other. The facades of such houses differ little in terms of their constructive solution. As a rule, the thickness of the walls of the two upper floors of buildings was assigned at least 2.5 bricks and increased as we moved downward by 0.5 bricks every 2 floors (according to studies carried out in Moscow). Such a wall served as a reliable load-bearing structure, was a good heat insulator, and from the outside it was a beautiful facade.
Those days are long gone, and today the outer walls of buildings are not homogeneous brickwork, but a multi-layer "cake", the inner layer of which has become effective thermal insulation.
What is a modern brick façade? This is a self-supporting brickwork with a thickness of 85 to 250 mm, firmly attached to the supporting wall structure. Such masonry can stand on the foundation, or it can start from the 2nd or 3rd floor. The latter is especially important during construction in the central part of cities, where the first floors of buildings, as a rule, are reserved for shops and offices with glass showcases or panoramic windows. And then there is a need to suspend the brickwork of the facade.
One of the hanging methods is offered by the Lithuanian company BAUTOPAS. The BAUT system produced by her consists of stainless steel brackets, reinforcement bars, clamps, ties and ventilation boxes. The essence of hanging is as follows. A number of brackets are attached to the building frame at intervals, usually of one brick. If it is necessary to hide the brackets, the first row of masonry is located below the level of the brackets (Fig. 1). The second row rests on the shelves of the brackets. The first 3 rows of masonry are reinforced with Murfor or BAUT longitudinal reinforcement. Thus, a reinforced stone belt is formed, supported by brackets. It serves as the basis for the overlying masonry.
Upon reaching a 2-storey height (in Russia, the recommended masonry height on brackets is 1 floor), the masonry is interrupted. A number of brackets are mounted, the process of forming a reinforced stone belt with subsequent laying is repeated (Fig. 2). Thus, by dividing the facades into separate fragments with deformation, temperature-shrinkage joints, brick facades of multi-storey buildings are being erected.
Brick lintels deserve special attention. If you look again at the old brick buildings, you can see what a serious aesthetic load the window and door openings bore.
At all times, architects tried to play up the openings, highlighting them from the general context, at least with a pattern of masonry. The use of clamps of the BAUT system complete with fittings allows you to make any lintel known in the architecture (Fig. 3).
With large openings, more than 2 m, there may be a danger of the lintel deflection or even its destruction. To avoid this, jumper brackets are additionally installed. Their number and distribution above the openings is calculated in each case separately.
Suspended brick facades offer great opportunities. Not tied to the foundation of the building, they do not constrain the architect's imagination, they allow the most daring architectural project to be realized.
The experience of using hinged brick facades in the restoration of historical objects deserves attention. It is no secret that the structure of old brick buildings is often in a deplorable state and cannot be repaired. In such cases, a decision is made to demolish the historical object and restore it to its former appearance. The photo shows an object in Vilnius, demolished and restored taking into account the requirements for thermal insulation.
The BAUT system has also proven itself in low-rise, cottage construction. The use of brick lintels, longitudinal reinforcement, flexible ties and other accessories for masonry significantly improves the quality of the facades being erected.
Without diminishing the importance of the listed brickwork accessories, let us dwell in more detail on flexible connections.
The idea of a multi-layer facade brick wall is not new. She is so old that it is hard to believe in it. Little known to a wide circle of compatriots, Russian engineer A. N. Gerard in 1829 proposed to arrange walls of two walls of ½ brick each, connected by metal ties, and fill the space between them with slag. A year before, the engineer had built an "exemplary" house in his estate Bolshoye Golubino near Moscow. The house has not survived, but the idea is alive and well and is widely used in modern construction. For a long time, only stainless steel metal rods with a diameter of 4 mm were used as ties. The wire diameter is optimal because not only reliably connects two walls into a single whole, but also allows slight movements of the facade wall in relation to the inner wall structure. This is necessary because the façade is constantly exposed to wind loads and thermal expansion. To this day, in European standards, only metal products are regulated as structural connecting elements. However, in recent years, along with metal bonds, bonds made of composite materials, such as basalt-plastic, have become widespread in Russia. These bonds are very strong, they are not "cold bridges", do not corrode in an alkaline solution. Time will tell whether the successful competition between basalt-plastic reinforcement and metal will serve as the basis for the widespread introduction of polymeric materials in construction.
Architect Y. Ohanyan
The exclusive representative of the Lithuanian company BAUTOPAS in Russia is the company Slavdom. In the online store of the Slavdom company you can familiarize yourself with the assortment of BAUT products. You will also find detailed information about the BAUT system on the manufacturer's official website.
