Currently, large-format bricks are increasingly being used to create permanent load-bearing walls instead of traditional solid bricks. ceramic blocks. This provides many advantages, first of all, the speed of wall construction increases. In size, a large-format ceramic block is much larger than a brick, while having a relatively low weight. It is easy and convenient for builders to work with such blocks; the walls from them grow by leaps and bounds and, most importantly, they can be lined with any finishing materials.
Opportunities and prospects
Large-format ceramic blocks are produced by several companies, in particular, Porotherm blocks are presented on the market, which have proven themselves well in our climatic conditions and are deservedly popular among house builders. The blocks serve long time, the wall made from them turns out to be strong and reliable, so there is essentially only one problem - the need for cladding. Like the vast majority of wall materials, ceramic block requires exterior finishing. And if some wall materials, let’s say, are “capricious” in terms of cladding - one cannot be plastered, another is undesirable to be finished with natural stone, which ultimately creates more headaches for both builders and homeowners - then there is no such problem with ceramic blocks. Of course, there is no common technology for all facing materials, and in each case both the methods and the accompanying materials will be different.
One of the most common questions is how to properly bandage/attach to a ceramic block. facing material. In practice, several methods of such fastening are used. One of them involves the use of flexible ties made of basalt plastic in the amount of five to seven pieces per square meter. Basalt-plastic flexible connections combine strength, durability and lightness. These connections connect the load-bearing and facing layers. Flexible connections can also connect the load-bearing wall with the facing layer through the insulation. In addition, finishing or insulating materials can be attached to a load-bearing wall made of ceramic blocks using anchors made of of stainless steel. Thus, a wall made of ceramic blocks can be faced, for example, with facade (facing) brick, which is considered the most durable finishing material. There are different varieties of it in color and texture modern market- hundreds, if not thousands, especially if you count imported bricks. Facade brick is intended for exterior finishing walls and foundations and simultaneously performs protective and decorative functions. You can also use ceramic clinker tiles with the same success; the material is just as strong and durable.
Great option cladding of large-format blocks can be natural or fake diamond. It is noteworthy that no special technologies will have to be used; the process is carried out standard, which means in an inexpensive way. A wall made of ceramic blocks is first prepared with a plaster composition with a mesh, after which the prepared cladding elements are glued to a special glue. If desired, a wall made of ceramic blocks can be completely covered with plaster; it is applied according to the manufacturer's instructions plaster mixture. As an option, you can use today’s popular and very inexpensive siding. In this case, the wall is also pre-plastered, after which the frame is mounted and siding is hung.
Finally, ceramic blocks interact perfectly with technology such as a ventilated (or curtain) façade. IN last years it is used more and more often, allowing, on the one hand, to protect the wall from external influences, and on the other, to ensure ventilation and normal humidity balance in the wall mass. The curtain facade is a system consisting of cladding and the so-called sub-cladding structure, the arrangement of which leaves a gap between outer covering and a wall. This gap ensures the free movement of air flow and, among other things, significantly improves the sound and heat insulation of the wall structure. The modern construction market is distinguished by a variety of panels for facades. Facade panels can be single-layer or composite (multilayer). Today we present clinker panels, porcelain stoneware, metal (iron, aluminum or copper), panels from natural stone, as well as fiber cement panels. Such panels are dyed in bulk, have a natural range of colors, and do not fade under the influence of sun rays and successfully resist any external influences. In general, it should be noted that finishing walls made of ceramic blocks is, in principle, no different from finishing walls made of other materials. The main thing here is to choose the right one necessary materials(dry mixtures, etc.) and use them according to the manufacturer's instructions supplied.
Nuances of technology
To ensure the quality of the coating in the process of facing walls from ceramic blocks, it is important to observe certain nuances of technology. Questions that arise in practice require unambiguous answers, for example, the question of the need for a ventilation gap between facing bricks and ceramic blocks. Is it needed at all? Experts say that if there is no insulation, there is no need to create a gap. If between load-bearing wall and the front layer has insulation, the gap is needed to dry it.
Or take such a nuance as the need to insulate a wall during the cladding process. This insulation may or may not be done if the wall, for example, is insulated from the inside. The decision in each specific case is determined thermotechnical calculation and depends on the design of the wall and the type of used wall material. At one time, large-format porous ceramic blocks were created specifically in order to exclude insulation from the so-called wall pie. Therefore, when using them neither internal nor external additional insulation, as a rule, is not required.
If the decision to insulate the walls outside is nevertheless made, subtleties may also arise here. You can take, for example, standard mineral wool insulation. However, in some cases it is preferable to install an external heat-insulating layer using facade thermal panels. Such thermal panels are a complex multi-layer system consisting of a moisture-insulating layer, insulation (polyurethane foam or polystyrene foam) and a decorative and protective layer, which can be clinker tiles ( ceramic brick). Fixed to the sheathing of buildings, these durable panels provide excellent protection against all adverse weather conditions.
If we talk about comparatively new technology facing walls made of ceramic blocks - the so-called ventilated (curtain) facades - it should be taken into account that since their development and introduction into construction, methods of thermal insulation have fundamentally changed. In the recent past, heat-insulating materials were often mounted to the inner surface of the wall, which not only reduced usable area premises, but also did not provide a sufficient level of heat conservation. The main difference of this technology was the transfer heat-insulating materials from internal space buildings outside. In conclusion, it is worth mentioning such a seemingly trifle as calculating the number of facing bricks. It is also produced in a special way. The basis for the calculation is the area of the front part of the brick, as well as the width of the vertical (10 mm) and horizontal (12 mm) seams. In this case, you should always have a five percent reserve, since during the cladding process some of the material may become unusable for one reason or another.
Text: Vladimir Mikhailov
Since the base on which the first row of blocks is laid is never level, the first row is placed on a leveling layer.To begin with, a thin layer of waterproof mortar is applied to the surface of the base, to the area of the future masonry. Then the layer is rolled out roll waterproofing, following the rule - flush with the surface of the future external wall and a 2-3 centimeter outlet inside, under the internal walls the outlet is arranged on both sides.
The next step a thicker layer is applied masonry mortar, which is aligned to provide single level. Before installing the blocks, a thin layer of pure cement should be applied to the surface of the leveling layer. This will prevent the slot block from being immersed in a relatively soft solution, which would negate the preliminary work on preparing the leveling layer.
After preparatory work begin installing the corner blocks using a level and a rubber mallet. Next, the distance between the corners is measured, and the first row of blocks is laid out completely, while horizontal sliding of the blocks is not allowed; each block along the tongue-and-groove direction is pushed in from above.
After laying the entire perimeter of the wall, work is stopped for 12 hours. And it begins again with the installation of corner blocks. The position of each block is checked using a level and a cord guide; the position is corrected using rubber mallet. It is also necessary to check the verticality of the masonry with a level and plumb line.
If necessary, you can give the blocks the required size using reciprocating saw or alligator type saws, more about this in the article How to cut ceramic blocks.
The connection of the outer wall with the inner walls and partitions is carried out using perforated steel anchors placed in the pastel seam of every second row. To prevent the load from the ceiling from being transferred to the partitions in the future, it is important to follow the rule - do not load-bearing walls should be 1-2 cm below the load-bearing walls. In the future, the gap can be filled with polyurethane foam.
Every day, upon completion of work, it is necessary to cover the masonry of slotted blocks with a tarpaulin or covering films, otherwise, in case of rain, the voids of the porous blocks will be filled with water.
A single-layer ceramic wall has significant advantages over double-layer walls. Porous ceramic blocks are very durable material, the service life of a wall made of such material is estimated by experts to be 100 years or more.
If directly compared with two-layer wall structures, then they major renovation will be required very soon, the forecast period is 30 - 35 years, and even 20 years for low-quality polystyrene. Ordinary cheap insulation will fail during this period and will basically lose its unique properties.
Other advantages of a single layer ceramic wall
A single-layer ceramic wall is much more resistant to all kinds of damage than a two-layer one. Violations facade finishing will not lead to the same consequences as if they disturbed the finish over mineral wool or polystyrene foam.
Also:
- There is no risk of moisture if construction technology is violated or layers are damaged. Indeed, if you violate the principles of insulation in double-layer walls, you can easily over-moisten the structure.
- A single-layer wall is generally cheaper. If the quality of the materials is comparable, then in any case, a single-layer structure will have a lower final price.
- easier, faster to build. During construction, simplicity and manufacturability often dictate design features. You need to look for insulation specialists to do the second layer correctly, etc. These questions simply disappear.
What is known
From blocks of porous ceramics it is possible to build a single-layer wall with satisfactory heat-saving properties for moderate and warm climates.
But in cold regions, a single-layer block wall cannot provide the necessary thermal insulation.
There it is necessary (it becomes more profitable) to build two-layer walls, in which the load-bearing layer is covered with insulation.
Heat-saving properties of ceramic blocks
A reduction in thermal conductivity in products made of porous ceramics is achieved due to the presence of many closed cavities with air. The production of ceramic blocks is in many ways similar to the production of ordinary bricks, but components are added to the material, which burn when fired, forming pores.
Hollow blocks and bricks with large internal cavities are formed from such a mass. As a result, the thermal conductivity coefficient of the ceramic block is 0.15 - 0.17 W/mK, and for hollow brick- 0.2 W/mK.
Humidity affects these values, but to a much lesser extent than for aerated concrete blocks, which have less porosity and a larger number of pores.
How to make the entire masonry and wall warm
Ceramic blocks of high precision manufacturing, with a height inaccuracy of no more than 1 mm (polished), can be laid on a thin layer of glue or on a special adhesive foam.
In these cases, the thermal conductivity coefficient of the finished masonry made of ceramic blocks does not increase significantly compared to the blocks themselves.
The masonry and wall may lose possible heat-saving properties if only a thick layer of ordinary heavy mortar is used. Then the large-scale cold bridges that form simply neutralize the achievements of warm ceramics.
Selection of blocks and mortar based on heat loss
Blocks are usually produced in lengths of 25, 38, 44 and 51 cm. They are placed across the wall, with the embossed side surface to the adjacent blocks. Then the thickness of the wall is equal to the length of the block.
Let's look at an example. For the Moscow region, the required heat transfer resistance of the walls of a house is no less than 3.15 m2*K/W. Approximately the same value is for masonry made of ceramic blocks 51 cm thick, made with heat-saving mortar or glue.
But if you use ordinary cement-lime mortar, then the heat transfer resistance of the wall will be 2.7 - 2.8 m2*K/W.
For the construction of private houses up to 3 floors in non-cold climates, it is more profitable to use blocks instead of bricks, the masonry of which is more expensive and much colder.
Reduce the number of additional blocks
Vertical joints between blocks with a tongue-and-groove side surface are not filled with mortar. Their filling is necessary in the case of using additional blocks with smooth edges or bricks.
A large number of such blocks can be in corners, wall bends, and near openings.
If the vertical seams between the blocks are filled with mortar, the thermal conductivity of the wall will increase. The number of such places should be minimized.
House designs made from ceramic blocks provide for distances that are multiples of an integer number of blocks, so the use of additional ones is kept to a minimum.
To increase heat savings, it is recommended to build a house in accordance with the project.
What size ceramic blocks to choose
A wall made of ceramic blocks with unfilled vertical joints must be plastered on both sides to reduce air permeability.
On the outside, only a special vapor-permeable plaster layer should be used. You can further increase the heat-saving properties of the wall if you apply warm plaster on the outside with a layer of 4 cm thick.
A popular technology is in which a wall made of ceramic blocks is lined with hollow façade bricks. The laying is carried out without leaving an air gap. The wall thickness increases by at least 12 cm. At the same time, the thermal insulation characteristics also increase slightly.
Therefore for southern regions and in Ukraine, ceramic blocks 38 cm long (masonry thickness 38 cm) plastered on the outside with a layer of warm plaster 4 -7 cm, or lined with hollow façade bricks. Such a wall will have for regions with mild winters satisfactory heat-saving properties.
Suitable wall width
If the heat transfer resistance of the wall turns out to be lower than the recommendations of SNiP 02.23.2003, then it is possible to compensate for the deficiency and bring the total heat loss of the building in accordance with the requirements of the standards by increasing the insulation of other building structures, in accordance with design solutions.
It should be taken into account that a wide wall places increased demands on the strength and size of the foundation.
A wall made of porous ceramic blocks can be wider than the base by no more than 20%, and up to 30% when confirmed by strength calculations in the project.
It is not economically profitable to build a ceramic wall wider than 63 cm (51 + 12), since it will be spent on insulation significant amount dear durable material(porous ceramics) which is not necessary due to strength requirements.
In fact, this is the condition for switching to the construction of two-layer walls with a narrow load-bearing layer in the northern regions.
Construction of wall insulation made of ceramic blocks, thermal insulation measures in various places of masonry
Reinforced concrete and metal elements structures that have much greater thermal conductivity than the wall itself, so they are necessarily fenced from the street side with an additional layer of insulation.
- Above window or doorways Crossbars are installed - reinforced concrete lintel beams. This standard elements specially designed for openings in wide walls. WITH outside they are fenced with a layer of at least 10 cm mineral wool And thin layer ceramics.
- The ceilings on the floors and the mauerlat timber for the roof must rest on a reinforced concrete frame, made as a solid structure above all load-bearing walls at the floor level, and evenly distributing the loads on the walls. This reinforced concrete frame (concrete belt) is fenced on the street side with at least 10 cm of moderately hard mineral wool insulation and additional ceramic blocks.
- The internal load-bearing walls are connected with masonry to the external walls. Blocks interior walls on the street side they are fenced in the same way.
- Reinforced concrete plinth on which load-bearing walls rest (masonry made of ceramic blocks can only rest on a monolithic strip foundation sufficient rigidity according to the design), the outside is enclosed with extruded polystyrene foam insulation (usually at least 8 cm thick according to calculation) or foam glass with a thickness of 12 cm or more.
How to Insulate Block Walls in Cold Climates
In cold climates, walls made of porous ceramics of a reasonable thickness cannot meet the requirements for heat conservation, so they must be insulated with an additional (second) layer of insulation.
In this case, the supporting layer of porous ceramics is made relatively narrow; usually the width of the masonry is from 25 cm. More vapor-permeable insulation layers made of mineral wool or low-density aerated concrete are used as insulation for the blocks.
The use of vapor barrier materials - polystyrene foam, extruded polystyrene foam, foam glass - creates a risk of wetting the load-bearing wall itself.
What insulation to use
The following insulation materials are used to insulate walls made of ceramic blocks.
- Rigid mineral wool slabs with a density of 125 kg/m3 and more. They are glued to the masonry and plastered on top with a thin layer of vapor-transparent plaster.
- Flexible mineral wool boards with a density of 45 - 80 kg/m3. They are placed under the façade trim lathing, covered with a vapor diffusion membrane, and additionally secured with dowels.
- Rigid slabs of aerated concrete with a density of 100 - 200 kg/m3.
IN Lately learned how to make low-density autoclaved aerated concrete with a thermal conductivity coefficient of 0.05 - 0.06 W/mOK and sufficient structural strength, class B1.0 (compressive strength from 10 kg/m3, vapor permeability coefficient 0.28 mg/(m*year* Pa).
How to make insulation
The slabs are laid in masonry on the foundation ( starting bar) and glued to the load-bearing layer, plastered with vapor-transparent plaster with fiberglass mesh.
These insulation materials can be lined with ceramic bricks, leaving a ventilation gap, and the wall will already have three layers, since the brick layer will be self-supporting and rests on the foundation.
Between the insulation and brick cladding a ventilation gap is left and upward air movement is ensured, similar to a ventilated façade.
When choosing insulation for walls made of ceramic blocks, the main factor remains the durability of the material.
For rigid mineral wool boards from famous manufacturers The service life is set at 35 years. But for aerated concrete blocks this figure is higher. Therefore, recently, aerated concrete has become a significant alternative to mineral wool.
Let us consider in detail why to fill the technological gap between the cladding and the Porotherm block with a solution based on perlite. And so, according to the Porotherm block laying technology, after the block is installed, the outer vertical seam must be carefully covered with mortar. Briefly, why this needs to be done, since masonry with a ceramic porous block is carried out with a groove - a ridge, and the block may not have the correct geometric shape or the worker will not place the block close to each other, then in the place where the groove-ridge will be there will be a gap, in other words, a gap. If you do not seal the vertical seam from the outside, but only plaster it from the inside, then closed convection will not work and the block will lose its thermal efficiency. In order to comply with the rules for laying a block, it was necessary to first raise the wall with a block, and then, when the seams were sealed, begin to lift the cladding. I do it the other way around, raise the lining by 2 - 3 rows of porotherm, then put the block down. This is convenient because you don’t have to install additional scaffolding for laying facing bricks, because both the scaffolding and the work on their construction cost money.
If you choose the most The right way first lay the block then the cladding, then here are some tips for you:
- Place connections in the mortar joint of the block in advance so that you don’t have to drill anything later.
- Put the house under the roof and then finish it with cladding.
- Do not buy facing brick in advance (it may begin to mold, there may be ants and they will drag soil there and the brick will be dirty, get wet in the rain and efflorescence will begin to appear on it).
- Leave the vent. the gap between the cladding and block 1 is 1.5 cm.
You may be wondering why I fill the gap with perlite mortar rather than regular mortar or leave it empty altogether? I decided to do this because the manufacturer recommends placing the ceramic porous POROTHERM block on a warm solution, and it is on perlite. I put POROTHERM 44 on a regular solution, but pouring those. I fill the gap with perlite mortar and close the vertical seams, additionally insulate the wall and remove cold bridges.
The composition of the mixture is perlite.
I made the pouring mixture as follows:
I took 2 buckets of M75 perlite for one batch, my bucket is 12 liters, a 130 liter concrete mixer, 1 bucket of sand, half a bucket of M500 cement, half a bucket of water, maybe more or less, and soap.
Now about the kneading process itself:
Pour water then, turn off the concrete mixer, set it with the hole at the top, carefully (perlite is very volatile), pour out two buckets of perlite, turn on the mixer and put it in the working position, turn for 7-9 minutes (perlite has this property, it first takes up water and begins to clump, then turns into mush) add water if necessary. After the slurry is obtained, fill a bucket of sand (do not mix with sand for a long time), the perlite is mixed with the sand, add cement and mix for no more than 2 minutes, it is no longer recommended that the perlite granules will be broken by the sand and the thermal efficiency will be lost.