Walls 

The construction of the walls of the house, purpose, types of walls, structural materials. Structural materials

A house is usually built not only for itself, but also for posterity. For it to stand for centuries, we need reliable, strong load-bearing walls in the house. From what material to erect them, we consider below.

Before choosing material for the future home, order its project, and then proceeding from it, you can closely engage in the purchase of material. The walls bearing the main load are erected from:

  • brick;
  • concrete blocks;
  • stone, which, like brick and concrete blocks, refers to heavy materials. Under them, the foundation needs an appropriate one;
  • wood, which is lightweight and can be saved on the foundation;
  • also from different modern materialshaving, as a rule, light weight. We are talking about aerated concrete, glued beams, ceramics.

It is necessary to proceed from such considerations:

  • how severe the climate in your area;
  • whether the house will be one-story or it is planned to erect 2-3 floors;
  • what materials are actually available in your market;
  • if your finances are enough to purchase certain materials.

Consider several options for load-bearing walls.

Load-bearing wall in a brick house

If you build a house of brick, then for financial costs it will be expensive, but it is strong and reliable, because this material is time-tested. When purchasing a brick, you should know that it happens:

Modern materials for the supporting walls of the house

Gas and foam blocks are very popular. Their advantage:

  • in relative cheapness;
  • in lightness;
  • in ease of installation;
  • in good thermal conductivity.

If we compare them with such traditional material as brick, then they:

  • much more fragile
  • less durable. This refers to the compression load;
  • their frost resistance is almost half lower than that of a brick;
  • moisture resistance is lower than even white brick.

For the bearing walls of a multi-storey building, neither aerated concrete blocks nor foam concrete blocks are suitable, but for construction country house   aerated concrete is quite acceptable. You should know when buying gas blocks:

  • they have a marking that indicates the density from D300 to D1200;
  • the relationship between density and thermal conductivity is inversely proportional: the higher the density index, the lower the thermal conductivity. Therefore, when choosing a high density, take blocks with a large width;
  • better are those gas blocks that have an end face. Its presence allows you to save on glue, since they do not need to fill vertical seams.


From this video you will learn how the load-bearing walls of a ceramic brick house are built:

And here the most environmentally friendly load-bearing walls are built from a completely unusual material - straw. Well, this option also has a right to exist:

The main structural part of the building is the walls. Walls are load-bearing structures, calculated to have sufficient strength, stability under vertical and horizontal loads.

Wall   It is a vertical fence that separates the room from the external environment or from another room.

Walls are divided:

  • depending on the perception of loads - on bearing, self-supporting   and non-bearing;
  • by the nature of the material - on stone, wooden, walls made of local materials, as well as combined

In this article we will consider the main types of walls by type of material - wooden   and stone.

Wooden walls

For the walls of low-rise buildings, the traditional material is wood. The most comfortable hygiene requirements are cobblestone walls   and chopped walls   from coniferous trees. Their disadvantages are sedimentary deformation in the first 1.5–2 years and low fire resistance.

Frame walls   justified in the presence of lumber and effective insulation. Note that frame walls do not require massive foundations, unlike chopped ones, they do not give post-construction deformations. Fire resistance and capitalism of frame walls increases with brick cladding.

Logs   it is advisable to harvest in winter, as the wood is less prone to decay, warping during drying. The moisture content of wood should be 80–90%. Logs should be without cracks, rot, not affected by beetle bark beetle and fungus. The quality of the material can be determined by hitting the butt of the ax, a clean and clear sound indicates good quality. Wooden houses are built with a height of no more than two floors.

By design   wooden walls of heated buildings are divided into chopped logs or beams, frame, panel and frame-panel.

Chopped Log Walls

Characteristic

Chopped Log Walls represent a design of logs stacked on top of each other in horizontal rows and connected in the corners by notches. The thickness of the logs in the upper cut for the outer walls of heated buildings located in the central strip of Russia is 22 cm, in the northern and northeastern regions 24–26 cm. The diameter of the logs is chosen the same, with a difference between the upper and lower cut not more than 3 cm.

Technology

Each row of logs in the wall is called crown. The crowns laid successively one on top of the other from the bottom to the top of the wall form a blockhouse. The first lower crown is called a flange; it is made 2-3 cm thicker than the other crowns.

The crowns are stacked with knots alternately in different directions and connected in length by vertical crest   (Fig. 10), and the joints of the crowns along the height of the wall are positioned apart. The crowns are rallied with the help of grooved grooves and inserted spikes with a size of 25x50x120.

Crowns stack groove down, thereby eliminating the possibility of water flowing into it. In the grooves between the crowns lay tow to seal the seam and insulation. Depending on climatic conditions, the groove width is from 12 to 15 cm.

Spikes   put through 1.5–2.0 m in height of the log house in a checkerboard pattern, rectangular (8x2 cm) or round (3-4 cm) section, 10-12 cm high. In the piers, the thorns are placed in each crown one above the other in the amount not less than two and positioned from the edges of the wall by 15–20 cm.

Within 1-2 years after the erection, the log house gives a draft of 1/20 of its height, due to drying of the wood and compaction in the joints of the tow. In connection with logging draft   nests for spikes should exceed the height of the spikes by 10–20 mm, and over the openings leave gaps of 6–10 cm, which are filled with tow and covered with platbands.

Seams between logs   to reduce blowing capacity, caulk is caulked for the first time immediately after installation of the walls and for the second time 1-2 years after the end of precipitation. In the corners of the building, the crowns mate with a notch with the remainder in the bowl or without the remainder - in the paw. With the method of pairing the crowns in the corners of the paw, that is, without residue, the wood is consumed in a smaller volume, so this method is more appropriate. In fig. 11 shows a section of a chopped log wall from the cornice to the foundation.

Advantages and disadvantages

Chopped log walls are highly durable and good. heat-shielding qualities, under favorable operating conditions, durability. Processing logs and walling is a laborious process requiring a large consumption of wood.

Cobblestone walls

Characteristic

Cobblestone walls   erected from horizontally stacked beams. The use of bars makes it possible to exclude the manual processing of logs, cutting of mates of corners, adjoining walls and go to the mechanized preparation of wall elements.

Procurement of material

Bars for walls   harvested at the factory with all the notches for mates and nests for spikes. Compared to log houses, the complexity of erecting block houses is much less, and wood consumption is reduced. Unlike timbered, tiled walls are assembled immediately on ready foundations.

Technology

Section of bars   for external walls take 150x150 mm and 180x180 mm. Depending on climatic conditions, for internal walls - 100x150 mm and 100x180 mm. The bars are stacked on top of each other with a tar between them laying and caulking seams. For better water drainage from the horizontal seam between the beams, a 20x20 mm chamfer is removed from the upper edge of the front part of the beam.

The rows of bars are interconnected cylindrical pins   with a diameter of 30 mm and a length of 60 mm, placing them at a distance of 1.5–2 m from one another. The crowns of the mating cobblestone walls are on the same level and connect them in corners, adjacencies and sections in various ways. The conjugation of the angle and the abutment of the walls using the keys is shown in Fig. 12 with the help of spikes with dimensions of 35x35 mm and 35x25 mm.

Cobble Wall Protection

Effective weather protection of cobblestone walls planking   or brick cladding, which protects the walls from moisture, increases thermal protection, reduces the effects of wind, with brick cladding of walls increases fire resistance. Brick cladding must be installed with a gap from the tiled walls at a distance of 5-7 cm, leave vents at the bottom and top of the brick cladding to provide ventilation.

Frame walls

Benefits

Frame walls   require less wood than log or block walls, are less labor intensive, and therefore more economical.

The basis of the frame walls is supporting wooden frame, sheathed on both sides by sheet or molded materials. Frame walls, due to their lightness, are practically not subject to shrinkage, which allows them to be sheathed or lined immediately after construction.

Wall protection

Frame walls must be protected from atmospheric moisture by outer cladding with overlapping vertical and horizontal joints and arranging plum from the protruding elements of the walls. Protection against water vapor is ensured by arranging a vapor barrier from a synthetic film, a glassine, or using other types of vapor barrier, laying them between the inner lining and the insulation.

Technology

For frame manufacturing   External and internal walls use boards 50 mm thick, as for the device of rafters and beams. With a thickness of 50 mm, it is recommended to use struts of supporting walls with a width of at least 100 mm.

Width of the frame racks   in the outer walls they determine the calculated thickness of the insulation, depending on the efficiency of the insulation itself and the calculated temperature of the outside air. The supporting racks of the frame are located at a distance of 0.5 m, linking with the dimensions of the window and door openings. Basement beams are located at a distance of 0.5 m. Corner racks of the frame are made of beams or composite boards, and ordinary ones from boards 50x100, or 60x120 mm.

The frame from the inside is sheathed with boards of any profile and section, plasterboard plates; typesetting, sheet wall panels and other finishing materials. On the outside, for lining the frame, they use a “lining”, siding, tes, thermobrick panels and other materials.

Warming

Insulation of frame walls   carried out using mineral and organic materials with a density of up to 500–600 kg / m³. Mineral, glass wool plates, expanded polystyrene are effective modern heaters, because they are fire resistant, lightweight, not subject to decay, exposure and penetration of bacteria, fungi, not destroyed by rodents. Organic heaters are susceptible to destruction by rodents, combustible, and rot; in addition, they must be treated with an antiseptic before filling and mixed with mineral binder - cement, lime, gypsum before use, then laid in wet layers of 15–20 cm, tamping. Such a backfill dries out within 4–5 weeks; therefore, prefabricated slabs and blocks of lightweight concrete should be used to fill the frame. The following materials are used for backfill: pumice, sawdust, gilak, shavings, peat and others, which are significantly inferior in their properties to modern mineral insulation.

Shield walls

Benefits

Difference panel wooden houses   from frame consists in the fact that their main structural parts consist of enlarged shield elements, made, as a rule, at the factory. The process of building panel houses comes down to installation at the construction site and finishing work. The construction of wooden panel houses reduces the complexity of the work, provides high installation rates.

Technology

In panel wooden houses, the basis of the walls is the lower binding of wooden antiseptic barslaid on the basement of the building and attached to it with anchor bolts. Wall panels are installed on the strapping. From above wall panels   fasten the upper harness laid on them, on which the attic floor is supported. Wall panels produce internal and external, which, in turn, are divided into deaf, window and door. The height of the shields is equal to the height of the floor, the width is taken equal to 600–1200 mm. Shields consist of cobblestone strapping and sheathing, internal and external, between which a heater is placed.

As a shield insulation, mattresses from mineral felt. A vapor barrier is placed under the casing on the inside of the shield in order to prevent the formation of condensation of water vapor inside the shield penetrating into it from the side of the room. To reduce blowing, paper is laid under the outer skin.

Shields are placed vertically and connected with nails. When connecting joints between shields, it is necessary to ensure sufficient density and non-blowing of the joint. In fig. 14b shows the recommended design of vertical joint of boards. The joint must be covered with continuous layers of air and vapor barrier.

In the joint lay mineral felt 20 mm thick, gluing it cold bituminous mastic. Then with the help of the lever device produce compression of the joint. In panel houses, ceilings are arranged with panel or beam.

Wall protection

When installing the basement and cornice nodes, it is necessary to take measures to protect them from freezing by the device insulated base   and an insulated frieze belt at the eaves, as well as from humidification with vaporous moisture in the internal air, arranging vapor barrier for this purpose. Under the basement, the underground is not insulated. The underground should be cold and well ventilated, and the structure floors above the underground   and especially the basement unit should have reliable insulation and vapor barrier, laid on top under the clean floor structure. To protect against freezing at the level of overlap, an insulated belt is arranged outside.

Stone walls

Homogeneous walls

Material

Homogeneous walls   made of ordinary hollow or light building bricks. In heterogeneous, lightweight walls   part masonry replaced the thickness of the wall with heat-insulating tiles and an air gap.

Technology

The walls are erected with a thickness of 1/2, 1, 11/2, 2, 21/2, 3 bricks and more, taking into account the thickness of vertical joints equal to 10 mm, brick walls have a thickness of 120, 250, 380, 510, 640, 770, respectively mm and more. The thickness of the horizontal joints is 12 mm, then the height of 13 rows of masonry should be 1 m.

When erecting brick walls, two masonry systems are used: two-row - chain and six-row spoon.

IN double row masonry system   row rows alternate with spoon rows. Cross joints in this system overlap 1/4 of the brick, and longitudinal joints overlap 1/2 of the brick (Fig. 16).

Six-row system   involves the alternation of five spoon rows with one poke. In each spoon row, the transverse vertical seams are tied into a half-brick, the longitudinal vertical seams formed by the spoons are tied in rows of rows through five spoon rows.

Masonry using a six-row system is simpler than double-row. To reduce the breathability of the walls, the front joints of the masonry are sealed with a special tool, giving the seams the shape of a roller, fillet or triangle. This method is called joint stitches.

disadvantages

The disadvantage of ordinary solid brick, clay or silicate, is its large volumetric weight and, therefore, large thermal conductivity.

Crowning cornices

Technology

Crowning cornicedepicted in fig. 17, brick masonry walls with a small extension - up to 300 mm and not more than 1/2 the thickness of the wall, can be laid out of brick by gradually releasing rows of masonry 60–80 mm in each row. With the removal of more than 300 mm, the eaves are arranged from prefabricated reinforced concrete slabs embedded in the walls.

The inner ends of reinforced concrete slabs are covered with precast longitudinal reinforced concrete beams, which are attached to the masonry using steel anchors embedded in it, thereby ensuring the stability of the cornice.

Lightweight brick walls

Characteristic

Lightweight brick walls, in which the brick is partially freed from heat-insulating functions unusual for it, by replacing part of the masonry with less heat-conducting materials, they can significantly reduce the consumption of bricks, thereby increasing material savings.

Classification

Lightweight brick walls are divided into 2 groups. The first group includes structures consisting of two thin longitudinal brick walls between which thermal insulation material is laid, the second group includes structures consisting of one brick wallinsulated with heat-insulating plates.

Brick walls with insulation from insulation panels

Characteristic

Brick walls with insulation   of heat-insulating panels (Fig. 19) consist of a bearing part - masonry, the thickness of which is determined only from the strength and stability of the wall, and a heat-insulating part - foam, gypsum or gypsum slag panels.

Advantages and disadvantages

Lightweight concrete stones   Compared with ordinary brick, they have lower bulk density and lower thermal conductivity, therefore, the use of ceramic stones for the construction of external walls can reduce their thickness. The disadvantage is that lightweight concrete stones of lower bulk weight have less strength and resistance to weathering.

Characteristic

Three hollow stones with large voids have dimensions of 390x190x188 mm. In the stitch rows, a stony stone with a smooth end surface is used.

After stones are laid in the wall, the voids in the climatic conditions of the middle and northern regions should be covered with slag, low heat conductive material, because with large voids, air exchange occurs in them, which increases the thermal conductivity of the wall. Filling voids with low-conductivity materials increases the complexity of masonry. To reduce air circulation in voids, three-hollow stones with non-through voids - five-walled stones are used.

Walls   must - protect, protect, and delight the eye. Walls are the heaviest, most labor-intensive and most expensive building structures.

By the nature of the perception of loads wallscan be bearing and not bearing. Bearing walls perceive the load from its own weight, the weight of floors and coatings, as well as from the wind. They transfer the load to the foundations, and non-bearing ( interior partitions) - on floors.

Distinguishing them is quite simple. The bearing wall is a natural extension and an integral element of the building structure, serves as a support for beams or concrete slabs of the floor, that is, it bears some kind of load. Try to mentally remove it: if this violates the integrity of the structure - the supporting wall.

A curtain wall is, as a rule, a usual internal partition of a house, designed to divide the volume into several parts or to highlight functional areas in the room.

It is made of lighter materials. Its dismantling does not entail a redistribution of loads in the building structure.

Walls are divided into:

Monolithic;

Small and large blocks;

Panel and panel board;

Wireframe;

Prefabricated (log cabin and timber);

Combined.

Construction materials

Materials for the walls are chosen taking into account the design, strength, durability, the required comfort and external expressiveness.

Wood (logs, boards, single and double layer frames with planking) is a traditional material for individual construction. Wooden log cabin - a dwelling based on centuries-old traditions. Such a house is not afraid of frost, especially when it has a fireplace or stove.

It can be a more modern building stylized as a hut, in which logs and profiled timber (solid or glued) are only finished, and mineral wool insulation is located inside the walls. The most serious drawbacks of such walls are fire hazard and high cost, as well as (if a solid beam is used) shrinkage deformations during the first 2-3 years of operation.

A special case of a wooden house is frame. Using this technology, up to 80% of private housing is being built all over the world, although our compatriots are still skeptical about it.

The basis of such a house is a wooden frame made of timber,   mounted on columnar foundations. Its walls resemble a sandwich. The filling is usually mineral wool insulation. From the outside, it is sewn up with moisture-resistant plywood or OSB boards, which are finished with facade plaster, sheathed with siding or faced with brick.

Interior decoration - from drywall.   Component Mounting Units frame house   (racks of the frame to the foundation, beams to racks and rafters to beams) in the West are thought out even at the design stage and, precisely executed by builders, allow the house to survive even during a hurricane.

Stone walls   most strong and durable. The material used is cobblestone, limestone, shell rock, tuff, sandstone. According to their thermal insulation properties, stone walls are significantly inferior to many others. Their use is advisable only in the southern regions. In the middle lane, stone is most often used for making socles, laying fences and retaining walls.

Concrete   - economical, durable and fireproof wall material. A wall made of monolithic reinforced concrete or heavy concrete blocks has a high bearing capacity, but low heat and sound insulation properties. To rid concrete of these shortcomings, it is given a porous structure. Such concretes are called cellular.

Another way to increase the insulating properties of concrete is to impart porosity to the aggregate. So get expanded clay blocks (aggregate - expanded clay, which is a foamed and baked clay), slag concrete blocks (aggregate - fuel slag), sawdust concrete blocks (concrete with the addition of woodworking waste).

Another modern technology using concrete is Thermodom. Such a building is erected from monolithic concrete with the use of stationary fixed formwork in the form of hollow polystyrene foam blocks that perform the role of thermal insulation after hardening of concrete.

Brick,   without exaggeration, the most popular wall material. Brick house   It is considered safer for health in comparison, for example, with concrete. Recently, the brick has undergone significant improvement: it is expanding not only the product range, but also developing new technologies for lightweight masonry.

But the unequivocal conclusion that the brick is good, and all other materials are bad, should not be done.

Heat saving

There are three options for insulation, depending on the location of the insulation in the building envelope: on the inside, in the thickness of the wall and outside.

Warming from the inside has two drawbacks: a decrease in the area of \u200b\u200bthe room and the risk of moisture condensation in the insulation layer, which can lead to dampness, mold, and subsequently even to the destruction of the wall. When finishing with drywall, the dew point can occur on the surface of the insulation in the place where it adjoins the wall, but only if moisture penetrates from the room.

To prevent this, a vapor barrier layer (in other words, a film) is provided, which is located between the insulation and the inner lining. Thus, the steam is removed from the room by ventilation.

Insulation "inside the wall" is used, for example, in timber frame houses and in brick masonry. In the latter case, the thickness of the inner layer is determined by strength indicators, and for the outer layer that protects the insulation from external influences, use front or plastered brick.

External insulation is the so-called “wet type” systems (with plastering or facade cladding) and a ventilated facade.

The “wet” type insulation system consists of three layers: thermal insulation (a plate of mineral wool or expanded polystyrene), reinforced (is an adhesive composition reinforced with a mesh) and protective and decorative. This system has many advantages: evaporation of condensate, heat accumulation in the building envelope, the absence of temperature deformations of the load-bearing wall and efflorescence on the facades, increased sound insulation, the possibility of use both on new and on reconstructed buildings. The disadvantages include seasonality of work.

The effectiveness of the “wet” type system depends on the compatibility of the layers. Its components are usually manufactured by various manufacturers, however, the responsibility for the quality of the system is assumed by one company - its developer.

The hinged ventilated facade consists of a cladding (plates or sheet materials) and a sub-cladding structure that is attached to the wall so that there is a gap for air between the protective and decorative coating and the wall. If the wall is additionally insulated and heat-insulating material is attached to it, a gap is left between the lining and the insulation.

Hinged facades allow load-bearing structures to work in “greenhouse” conditions: in the cold season, the wall remains dry and warm, and in the summer - cool, it “breathes” freely, thereby increasing the comfort of the premises.

Hinged facades are assembled from high-quality elements of full factory readiness, do not require additional decoration, and there are no “wet” processes during their installation. A variety of materials can be used as cladding: natural stone, ceramic granite, cement-fiber panels, vinyl siding, polyurethane, polyester and polypropylene panels.

Porous concrete blocks

With a relatively small volumetric weight, blocks of porous concrete have a sufficiently high strength, which makes it possible to make floors from ordinary reinforced concrete hollow slabs.

Depending on the production method, cellular concrete is divided into foam and aerated concrete.

Aerated concrete   receive, introducing into the cement mortar special substances that cause the process of gas formation. Most often this is aluminum powder. Aluminum reacts with the products of cement hydration; hydrogen is released, which causes the cement mortar to become porous. When the concrete hardens, its porosity is maintained.

Foam concrete obtained by mixing cement with specially prepared foam. Bubbles containing air are evenly distributed throughout the volume of the mixture.

Aerated concrete can have different porosity. The density of concrete depends on the number and size of pores, that is, the weight of one cubic meter: the more pores, the lighter it is, the higher its heat and sound insulating properties, but less strength. With a decrease in porosity and an increase in density, strength increases, but the heat and sound insulating properties deteriorate. Depending on the density of aerated concrete, its purpose also changes (for external or internal walls).

Cellular concrete   do not burn and do not support combustion. They are impeccable from an environmental point of view - abroad they are often called "bioblocks". Like wood, foam blocks can be sawed with a hacksaw, nailed into them, made of arches, which allows you to give the house an architectural expressiveness.

Dimensional accuracy allows you to put blocks on adhesive mixtures with a minimum joint thickness (3-5 mm), which minimizes the number of “cold bridges” and significantly reduces heat loss. In addition, the cost of subsequent wall decoration is significantly reduced.

Due to the high thermal resistance, foam concrete buildings are able to accumulate heat, which reduces heating costs by 20-30%. Weight reduction also leads to savings on foundations.

Which is better: aerated concrete or foam concrete - definitely can not be said. Foam concrete is cheaper, however, it loses somewhat in strength. In Germany, for example, they are often used together: load-bearing walls are laid from more durable aerated concrete blocks, and foam concrete is used for partitions that do not carry significant loads.

Many private developers think that, using foam blocks, they will immediately solve all problems - both in terms of heat and strength. However, the construction of a box of foam blocks with a density of 800, sufficient in strength, although it is quite cheap, but entails the need for insulation - blocks with a lower density will not cope with the bearing functions.

A definite plus of using foam blocks is that construction is fast and can be divided into two stages: first, erect a box, install windows and doors, install a roof, and after saving money, after a year or two, proceed with insulation and decoration. But in winter, it is better not to live in an insulated house: when heating, walls can be covered.

Brick walls

Brick - expensive and prestigious construction material. The brick mansion is an indicator of the security of its owners and the seriousness of their intentions: with any architecture, this is a house for several generations.

Brick is a multifunctional material. He performs both the supporting role and the insulation - and quite convincingly. However, according to today's standards, it does not pass as a heater (unless, of course, the walls are not a meter thick). Therefore, a multilayer structure is constructed in which only the supporting role is assigned to the brick, and other materials take on the insulation function (see above “Heat Saving”).

By bearing capacity   almost any brick is suitable for the construction of a private house - if only its brand matches the design, the appearance is not important. As for thermal conductivity, in this ordinary brick is inferior to large hollow brick blocks.

So, we offer you three options for the design of external walls. The first is a brick wall with insulation from the inside, the second is a wall of foam blocks with external insulation and cladding siding, the third is a wall of foam blocks with external insulation “wet”.



Each of the wall materials has its own advantages and disadvantages, which determine the scope of their application.

To make it easier for you to decide on the choice of material for the construction of your country house, below we will consider the characteristics of various blocks and bricks.

Expanded clay block

Compared with other blocks, it has a higher level of strength and frost resistance, which together gives a significant service life, as well as excellent structural reliability. Due to the fact that the level of water absorption at the expanded clay block is the lowest, it does not need care and is resistant to weather phenomena.

Another positive feature is the absence of shrinkage - this allows in the future to avoid the appearance of cracks on the walls, as well as changes in the geometry of the walls.



Due to the long cooling period, the level of comfort increases, since temperature differences inside the building are reduced. The low cost of these blocks also relates to the advantages of the material.

If we talk about the shortcomings of expanded clay concrete blocks, then this is an imperfect (in comparison with foam concrete) geometry. The same applies to the weight of the blocks - it is quite large.

Foam concrete block (foam block)

It has less weight, as well as perfect geometry - this greatly facilitates the installation of walls. The strength margin of the foam block is sufficient, but this is subject to competent insulation and wall insulation from atmospheric effects, because frost resistance is quite low, and water absorption is close to 100%.

A foam block construction can have a long service life only if it is properly insulated.



As a minus, the inconvenience of fasteners is noted (the porous structure of the blocks does not allow the dowels to be securely fixed in it). In addition, the porous structure of the material is a convenient environment for the appearance of a variety of fungi. It has a shrinkage, as a result of which cracks may appear on the walls of the building. The cost is pretty high.

Brick

Like claydite-concrete blocks, brick has a good margin of safety, as well as sufficient frost resistance. Due to this, brick walls are durable and resistant to atmospheric phenomena. Due to the low level of water absorption, brick can also be used as a facing material.



Among the minuses, it is necessary to note the complexity of installation, low thermal insulation properties, the high cost of both the material itself and the masonry services, and a rather high consumption of masonry mortar.

Gas silicate block

It has the smallest weight, as well as perfect geometry. This reduces time. construction workfacilitates installation of material. Another advantage is the ability to lay blocks on glue, which minimizes the inconvenience when working in residential apartments.

The disadvantages are the following qualities of the gas silicate block: low level of strength, frost resistance, high level of water absorption - this limits the scope of its application only to dry and warm rooms as a material for partitions.



In addition, this material, like foam concrete, is prone to the appearance of a fungus. It has shrinkage, which leads to the appearance of cracks on the walls.

Sawdust concrete block

The advantage is a rather low cost, as well as low weight. However, due to the high level of water absorption, as well as the insufficiently high level of frost resistance, the life of the walls made of this material is limited.



In addition, sawdust concrete blocks have poor geometry, because the sawdust included in the concrete changes the geometry during the pressing process.

Cinder block

This building material is now obsolete. The advantages are low weight and low cost of blocks. Due to the use of blast furnace slag as a raw material, it has a low level of environmental friendliness.

In addition, the cinder block has poor water absorption and frost resistance, which significantly reduces the service life of the walls.

To date, it has been replaced by an environmentally friendly expanded clay concrete block, which, by the most important indicators, is much superior to cinder blocks.



So which block to choose? Builders in European and other developed countries give preference to expanded clay concrete blocks, as the most optimal option for a combination of parameters. In Europe, the share of construction from expanded clay concrete blocks exceeds 50%.

Brick is also widely used, but more as a facing material, which contributes to its presentable appearance and level of durability.

From the above data, we can conclude that for the erection of the walls of country houses, the expanded clay block is the best material, and it is better to choose a brick for facade material.

Structures of external walls of civil and industrial buildings

The exterior walls of civil and industrial buildings are classified according to the following criteria:

1) by static function:

a) bearing;

b) self-supporting;

c) non-bearing (mounted).

In fig. 3.19 shows a General view of these types of external walls.

Load-bearing exterior walls   perceive and transfer to the foundations their own weight and loads from adjacent structures of the building: floors, partitions, roofs, etc. (at the same time they carry the bearing and enclosing functions).

Self-supporting exterior walls   perceive the vertical load only from its own weight (including the load from balconies, bay windows, parapets and other wall elements) and transfer them to the foundations through intermediate supporting structures - foundation beams, grillages or basement panels (at the same time carry out the bearing and enclosing functions).

Curtain (curtain) external walls   floor-by-floor (or through several floors) are based on adjacent supporting structures of the building - floors, frame or walls. Thus, curtain walls perform only a protecting function.

Fig. 3.19. Types of external walls by static function:
   a - bearing; b - self-supporting; c - non-bearing (mounted): 1 - overlap of the building; 2 - column frame; 3 - foundation

Bearing and non-bearing external walls are used in buildings of any number of storeys. Self-supporting walls are based on their own foundation, so their height is limited due to the possibility of mutual deformation of the outer walls and internal structures of the building. The higher the building, the greater the difference in vertical deformations, therefore, for example, in panel houses, the use of self-supporting walls is allowed at a building height of no more than 5 floors.

The stability of the self-supporting external walls is ensured by flexible connections with the internal structures of the building.

  2) According to the material:

but) stone walls   erected from brick (clay or silicate) or stones (concrete or natural) and are used in buildings of any number of storeys. Stone blocks are made of natural stone (limestone, tuff, etc.) or artificial (concrete, lightweight concrete).

b) Concrete walls   They are made of heavy concrete of class B15 and higher with a density of 1600 ÷ 2000 kg / m 3 (load-bearing parts of the walls) or light concrete of classes B5 ÷ B15 with a density of 1200 ÷ 1600 kg / m 3 (for heat-insulating parts of the walls).

For the manufacture of lightweight concrete, artificial porous aggregates (expanded clay, perlite, shungizite, agloporite, etc.) or natural light aggregates (crushed stone from pumice, slag, tuff) are used.

When erecting non-supporting external walls, cellular concrete (foam concrete, aerated concrete, etc.) of classes B2 ÷ B5 with a density of 600 ÷ 1600 kg / m 3 is also used. Concrete walls are used in buildings of any number of storeys.

in) Wooden walls   used in low-rise buildings. For their construction, pine logs with a diameter of 180 ÷ 240 mm or beams with a section of 150x150 mm or 180x180 mm, as well as board or glue boards and panels with a thickness of 150 ÷ \u200b\u200b200 mm, are used.

d) walls made of non-concrete materialsmainly used in the construction of industrial buildings or low-rise civil buildings. Structurally, they consist of external and internal sheathing of sheet material (steel, aluminum alloys, plastic, asbestos cement, etc.) and insulation (sandwich panels). Walls of this type are designed as load-bearing only for one-story buildings, and with higher floors - only as non-load-bearing.

3) by constructive decision:

a) single layer;

b) two-layer;

c) three-layer.

The number of layers of the exterior walls of the building is determined by the results of the heat engineering calculation. To comply with modern standards for heat transfer resistance in most regions of Russia, it is necessary to design three-layer structures of external walls with effective insulation.

  4) by construction technology:

a) by traditional technology   hand-made masonry stone walls are being erected. In this case, bricks or stones are stacked in rows along a layer of cement-sand mortar. The strength of the stone walls is ensured by the strength of the stone and mortar, as well as the mutual dressing of vertical joints. To further increase the bearing capacity of masonry (for example, for narrow piers), horizontal reinforcement with welded meshes is used after 2 ÷ 5 rows.

The required thickness of the stone walls is determined by the heat engineering calculation and linked to standard sizes   bricks or stones. Brick walls with a thickness of 1 are used; 1.5; 2; 2.5 and 3 bricks (250, 380, 510, 640 and 770 mm, respectively). Walls made of concrete or natural stones when laying in 1 and 1.5 stones have a thickness of 390 and 490 mm, respectively.

In fig. 3.20 shows several types of solid brickwork and brick blocks. In fig. 3.21 shows the construction of a three-layer brick wall with a thickness of 510 mm (for the climatic region of the Nizhny Novgorod region).


Fig. 3.20. Types of solid masonry: a - six-row brickwork; b - two-row brickwork; in - a laying from ceramic stones; g and d - masonry made of concrete or natural stones; е - masonry made of aerated concrete stones with an external brick lining

On the inner layer of a three-layer stone wall, ceilings and load-bearing roof structures are supported. The outer and inner layers of brickwork are interconnected by reinforcing mesh with a vertical step of not more than 600 mm. The thickness of the inner layer is accepted 250 mm for buildings with a height of 1 ÷ 4 floors, 380 mm - for buildings with a height of 5 ÷ 14 floors and 510 mm - for buildings with a height of more than 14 floors.

Fig. 3.21. Three-layer stone wall:

1 - inner carrier layer;

2 - a layer of thermal insulation;

3 - air gap;

4 - outer self-supporting (facing) layer

b) fully assembled technologyused in the construction of large-panel and volume-block buildings. In this case, the installation of individual building elements is carried out by cranes.

The outer walls of large-panel buildings are made of concrete or brick panels. The thickness of the panels is 300, 350, 400 mm. In fig. 3.22 shows the main types of concrete panels used in civil engineering.


Fig. 3.22. Concrete panels of external walls: a - single layer; b - two-layer; in - three-layer:

1 - structural heat-insulating layer;

2 - a protective and finishing layer;

3 - a bearing layer;

4 - thermal insulation layer

Volumetric-block buildings are prefabricated buildings that are mounted from individual factory-made room blocks. The outer walls of such volumetric blocks can be one-, two- and three-layer.

in) monolithic and precast monolithic construction technology   allow to build one-, two- and three-layer monolithic concrete walls.


Fig. 3.23. Prefabricated monolithic external walls (in plan):
   a - two-layer with an outer layer of thermal insulation;

b - the same with the inner layer of thermal insulation;

c - three-layer with an outer layer of thermal insulation

When using this technology, the formwork (form) is first installed in which the concrete mixture is poured. Single-layer walls are made of lightweight concrete 300–500 mm thick.

Laminated walls are prefabricated-monolithic using the outer or inner layer of stone blocks made of cellular concrete. (see fig. 3.23).

  5) the location of the window openings:

In fig. 3.24 shows various options for the location of window openings in the outer walls of buildings. Options but, b, in, g   used in the design of residential and public buildingsoption d   - when designing industrial and public buildings, option e   - for public buildings.

From consideration of these options, you can see that the functional purpose of the building (residential, public or industrial) determines the design solution of its external walls and the appearance as a whole.

One of the main requirements for external walls is the necessary fire resistance. According to the requirements of fire safety standards, the supporting external walls must be made of fireproof materials with a fire resistance of at least 2 hours (stone, concrete). The use of hard-burning load-bearing walls (for example, wooden plastered) with a fire resistance of at least 0.5 hours is allowed only in one-, two-story houses.



   Fig. 3.24. Location of window openings in the outer walls of buildings:
   a - wall without openings;

b - a wall with a small number of openings;

in - panel wall with openings;

g - supporting wall with reinforced piers;

d - wall with hinged panels;
   e - fully glazed wall (stained glass window)

High requirements for the fire resistance of load-bearing walls are caused by their main role in the safety of the building, since the destruction of load-bearing walls in a fire causes the collapse of all structures and the building as a whole.

Non-load-bearing exterior walls are designed to be non-combustible or hardly combustible with lower fire resistance limits (from 0.25 to 0.5 hours), since the destruction of these structures during a fire can only cause local damage to the building.