Surely every person who decides to build own house and going through different building materials, choosing the most suitable one, he heard about the shell rock. And there is nothing surprising here. In some regions, shell rock is the main building material. For example, many houses in the Crimea and other regions of our country adjacent to the seas are built using shell rock.
Shell house in Crimea
Today, thanks to the developed freight transportation, you can buy shell rock in any major city in Russia, regardless of how far it is located from the seas and deposits of this wonderful building material. However, before you build your housing from shell rock, you should learn more about it, about its structure, pluses and minuses. Only then can you make the right decision - objective and well thought out.
Shell rock is one of the special varieties of limestone. This is a mountain sedimentary rock created by nature itself over many millennia at the bottom of a large sea. For thousands and millions of years, various single-celled microorganisms, as well as mollusks, dying, fell to the bottom of the seas. Under great pressure they were compressed, turning into a durable porous material, which is widely used today in construction.
Therefore, the shell rock (or, as it is also called, shell rock) is nothing more than shells and fragments of tiny inhabitants of the salty seas. It is for this reason that experts attribute it to rocks of zoological origin.
Almost 100% shell rock is calcium carbonate.
However, in addition to calcium, it contains a certain amount of iodine and sea salt. This can be called a significant plus, but we will return to this issue in more detail a little later.
Projects of shell houses
Projects of shell houses are striking in their diversity. Due to its versatility and shape (it is a piece material), it is possible to build a building of any geometry, with any architectural delights.
An example of a shell rock house project with original geometry Shell rock can be used for construction ground floor, apply for the construction of capital bearing walls first and second floors, build an attic from it. For each specific solution selected material brand. This guarantees an ideal ratio of reliability and weight of the structure.
The weak point of the shell rock house projects are the balconies with the removal.
For their arrangement, it is necessary to use a special plate, which will become the basis of the balcony. Console attachments are practically not used. But balconies placed in niches and hidden in the geometry of the facade will look great.
The choice of material does not play on the appearance and style of the exterior. Both one-story estates and two or three-story villas are created from shell rock.
project of a three-story house from a shell rock It can be classic European houses with tiled roofs, as well as Gothic castles with towers and gabled roofs. The shell rock is perfect for both a year-round home and for dacha building used seasonally. Due to the porosity of the material, shell rock houses are quickly heated to the required temperature, which is easy to maintain at no extra cost.
All projects of houses made of shell rock, without exception, require mandatory facade finishing.
It's not just the aesthetic side of the issue. The shell rock itself, unless of course it is decorative facade tiles, and the building block material looks very unpresentable. The special structure of the shell rock is such that the pores of the material can be through. And in this case, it will be impossible to achieve the heat saving indicators promised by the manufacturer.
Most frequent materials for finishing facades - wood and pvc. Special panels are mounted on the assembled frame. This technology makes it possible to good ventilation, which shell walls need, but at the same time protect them from wind and drafts. decorative plaster and painting is not recommended, as this will worsen the vapor barrier properties of the material, and will also affect the environmental friendliness of the building.
If you like houses made of block and brick, but their cost scares you away, you can safely take a closer look at the projects of shell houses, or adapt the project you like to use this building material. In most cases, it will be possible not only to save on material and reduce the cost of work, but also to increase operational properties: heat preservation, sound insulation, vapor permeability.
Scheme of thermal insulation of a shell rock house Thanks to this, to build a truly environmentally friendly house with an excellent microclimate and self-regulating air humidity.
What can be made from shell rock
The construction of shell houses is quite common in many regions of our country. But what exactly can be built from this material? As it turns out, it can be used in almost any area of private construction. From it you can build:
Read also
Projects and construction of houses from polystyrene concrete
As you can see, having a sufficient amount of high-quality shell rock, you can easily build not only the house itself, but also equip the entire territory adjacent to it. Therefore, there is nothing surprising in the fact that the demand for this material is very high, and reviews on it, with correct use, extremely positive. However, in order not to regret in the future that you chose a shell rock for building a house, it would not be superfluous to find out about its pluses and, no less important, minuses.
Project one-story house with an attic of shell rock Advantages and disadvantages of shell rock
Each building material has certain disadvantages and advantages. Of course, the shell rock is no exception. To begin with, it is worth talking about its advantages: they are much more numerous than the disadvantages.
These are just the main advantages of the material. But this is already enough for a person who is not even very well versed in construction and building materials to understand that he will not have to regret such a choice. However, for objectivity, it is worth listing the shortcomings that this material.
Well, now you know both the pros and cons of this material. So, you can decide whether to build the cottages of your dreams from shell rock or prefer another building material.
Some more interesting facts about the shell rock
Surely many people who decide to build their house from shell rock will be pleased with the fact that this material, due to its unique chemical composition, is not at all afraid of corrosion and decay. In addition, it does not burn at all, although with prolonged contact with an open flame it can lose strength and simply collapse.
The porosity of the shell rock can vary significantly - from 22 to 70 percent.
It depends on the place of extraction, as well as the age of the shell rock. Of course, this affects the strength and thermal insulation characteristics. Therefore, before starting construction, it will be useful to know the characteristics of a particular material.
The cost of a shell rock is a rather complicated issue. If you can buy shell rock in the places of its extraction simply for a surprisingly low price, then in other regions the price can be several times higher. And the further your city is from the shell rock deposit, the higher the cost of the material will be.
This is what a shell rock deposit looks like So find out in advance in a specialized store where the material is brought from and what its cost is. This will allow you to more accurately calculate the cost of purchasing materials, and you will definitely not be disappointed with excessively high costs when you decide to build your own. Vacation home from this material.
The color of the shell rock also depends on the deposit. In some places it has a rich yellow or light brown color, while in others it is white or gray. Also, a huge number of shades are possible. Therefore, it will be relatively easy to choose exactly the color that would fully meet your requirements.
On the territory of Russia, shell rock of various grades is mined: from M-15 to M-35. They differ not only in color, but also in performance. For example, the M-35 is able to withstand significant physical exertion, which allows it to be used for basement or foundation equipment.
But the shell rock brand M-15, having in its composition a large number of sand, cannot boast of high strength. Therefore, it is most often used as thermal insulation material and for the construction of self-supporting partitions.
As a building material, shell rock is widely used in the coastal regions of southern Ukraine. The local builders have gained extensive experience in the construction and operation of shell houses. When starting to build such a house, it should be borne in mind that this natural material has a number of features that distinguish it from artificial building stone (concrete blocks, bricks).
Shell rock has a relatively low density, which is why many people consider it not a very reliable material for the construction of buildings. Therefore, the construction of a shell rock house needs justification.
As an example, we will give a simplified calculation for a three-story house with shell rock walls and reinforced concrete floors. The thickness of the walls in our calculation is 38 cm (one stone).
It should be noted that the calculation of the house will be made only for the conditions of seismically calm areas. Such areas in the figure below are marked in blue with the number 5 (illustration corresponds to the provisions of DBN B.1.1-12:2006 "Construction of buildings in seismically hazardous areas):
For areas of Ukraine with a higher degree of seismic hazard, the following additions must be made to the design of the future shell rock house:
- arrangement of a reinforced concrete frame and reinforced concrete belts;
- increase in the thickness of walls and piers;
- the use of shell rock of higher grades;
- reduction of free wall spans.
If all the above measures are taken, the question of the bearing capacity of the stone will disappear.
IN Table 1 the degree of strength of the shell rock is given different types. For our calculations, we will choose the lowest strength, that is, the “weakest” option - “Crimean central and western (finely porous yellow). The average brand of its strength is only 6M.
1.
In our calculations, only the area of \u200b\u200bthe walls on which reinforced concrete floors will be based will be taken into account. These overlaps are highlighted in red in the following figure. This zone bears the maximum load. The area of the wall sections on which the floor slabs are pressed is 56 X16 cm². 2. Now you need to calculate the weight of the shell rock walls with the above thickness of 38 cm. The height of such walls is 9 m (three floors). We multiply the total volume of the walls by the density of the shell rock 1150 kg / m3 (taking into account the density of the masonry mortar 1800 kg / m3) and we get 55 750 kg - this is the weight of the walls of our future home.
3. Next, you need to calculate the weight of three reinforced concrete prefabricated floors (first floor, second and attic). For calculation, we take PK-60-12 plates. Standard weight one such plate - 2100 kg. In total, 18 slabs will be needed for construction. Considering the thickness of the screed (3 cm), the total weight of the floor slabs will be 4Z 905 kg.
4. Then we calculate the load of the roof on the floor. For the correct calculation of the roof, we take the heaviest tile at an angle of 45o. The specific load of the roof projection is 80 kgf/m2. Let us take into account that for Kyiv snow load averages 70 kgf/m². As a result, we get that the load from the roof (6x8 m) on the floor is 7200 kg.
5. The total weight of the house structures = 106,855 kg.
6. Specific load on the lower row of stone: load on the block = 106 855 / 56 Z16 = 1.9 kgf/cm2.
7. Design resistance compression of low strength natural stone masonry correct form(our shell rock brand M6 and mortar brand M10) = 2.16 kgf / m². (Data taken from SNiP II-22-81 "Reinforced masonry and stone structures", table 7).
As we can see, despite a very heavy three-story house with three reinforced concrete floors, a tiled roof and concrete screed the maximum load still does not exceed the permissible - even when using the least durable shell rock.
Of course, our calculation for a shell house was rather simplified. We did not take into account the effects of window and doorways, as well as some other factors. However, even after such calculations, we were able to prove that the shell rock is quite suitable for use as a self-supporting building material in the construction of individual houses.
MASONRY OF WALLS FROM SHELL
It must be remembered that the mortar used for laying shell rock walls must be plastic. If the solution turns out to be too hard, it will be difficult even for experienced masons to lay walls from shell rock. The "correct" masonry mortar should not spread, but at the same time be easily pliable. To make the best solution, you will need:
- cement PC-400 (1 bucket);
- sand (4 buckets);
- water (about 1 bucket).
When kneading such a composition without special additives, it will turn out to be too hard and unsuitable for laying shell rock. If you try to make it less rigid by adding water, the solution will begin to delaminate rapidly, which will lead to an even greater loss of plasticity. Therefore, when mixing the solution, it is necessary to use a suitable additive that will increase the characteristics of its plasticity. For this purpose it is recommended to use the additive DOMOLIT-TR.
To prepare 1 cubic meter of solution, you will need about 0.5 kg of such an additive (the exact dosages are indicated in the instructions). If it is not possible to buy an additive, you can use the usual one instead. liquid soap or detergent for dishes in the proportion of 10 ml per liter of water for mixing the solution.
In the photo you see a masonry mortar, the consistency of which is optimal for laying shell rock walls.
If the volume of masonry is 5000 blocks of shell rock or more, it will be more profitable to use a concrete mixer to mix the mortar. If there is no concrete mixer, the efficiency of the masons team will noticeably decrease, since one worker will have to be allocated to mix the mortar. That is, a concrete mixer under such conditions will pay for itself very quickly. In addition, it is useful for preparing mortar and concrete during other construction works.
If the volume of masonry work is planned to be small, the mortar for laying shell rock can be kneaded by hand. The kneading is done on an ordinary steel sheet or some other waterproof, durable surface.
The set of tools needed to build a shell rock house is as follows:
- Master OK;
- mallet ( rubber mallet);
- kapron thread;
- measuring corner;
- high-quality building level;
- buckets for solution. 
Should be given Special attention quality building level, since the accuracy of the masonry will depend on it. Don't buy cheap levels with a weak bar. As for buckets, it is also not recommended to save on them: it is better to buy not plastic, but steel buckets that will not break under the weight of the solution.
The laying of the outer walls of a shell rock house starts from the corners (just like the laying of any other stone). The most time-consuming and responsible work at this stage is to bring the corner of the walls evenly. In our case, this task is complicated by poor geometry and irregular shape shell rock blocks. It is better to entrust the laying of corners to the most experienced masons. And if you decide to carry out the masonry yourself, without having such experience, invite a “consultant” bricklayer to show you how to use the building level correctly.
This is how the process of laying walls from shell rock looks like:
It is necessary to lay the blocks so that the upper corner of each block “looks” into the thread, but not close to it, but at a distance of 2 millimeters. If the block is applied close to the thread, then it will be pressed through, which will lead to an arcuate curvature of the entire row. By properly maintaining the masonry along the thread, you will eliminate all possible errors.
If the walls of the house, as in our case, are laid one stone wide, the masonry should be dressed every 4th row of blocks. Bandaging can be done in two ways:
- laying a number of blocks across the wall ("poke");
- laying a masonry mesh 50x50x4 mm in the seam between the rows.
Wall bonding is used to bind the wall of the house, making it more monolithic and durable. The red arrows in the next photo indicate the rows of blocks with wall bonding:
FLOOR EQUIPMENT IN A HOUSE FROM SHELL STONE
Ceilings in a house with shell rock walls can be done again in two ways:
- on masonry, directly on the masonry mortar;
- along the reinforced concrete belt.
In seismically safe regions, marked in blue in the first figure in this article, floors can be made without arranging a reinforced concrete belt (with a wall thickness of one stone, 38 cm). According to SNiP II-22-88, the length of the plate support surface must be at least 12 cm.
The design of the prefabricated reinforced concrete floor along the walls made of shell rock without a reinforcing reinforced concrete belt is as follows:
The device of a reinforced concrete belt for private residential buildings is necessary during construction in a seismically unsafe area, and also if the thickness of the walls is insufficient for stability (for example, when laying half a stone, 18 cm). This is how the belt device looks like (in the diagram: 1 - concrete belt; 2 - formwork):
Since the shell stone masonry has an uneven surface, it is impossible to lay the slabs exactly on the masonry. Often a level difference of 5-15 mm is formed between the plates. Given this, in order for the ceiling of the floor panels to turn out to be even, it is possible to make a leveling concrete belt, on which the slabs will then be laid. However, this measure will only help if the plates themselves are perfectly even. Experienced Builders note that the surface of the factory reinforced concrete slabs often uneven, which excludes the possibility of making a smooth ceiling without subsequent additional finishing.
INTERIOR FINISHING OF THE WALLS OF THE HOUSE FROM SHELL STONE
The best option for finishing - this is plaster, since it keeps perfectly on the shell rock, due to its porous rough surface. Professional builders do not recommend finishing shell walls with drywall on a galvanized profile or wooden beam because drilling this stone to set the profile is very difficult. Due to the heterogeneous structure of the shell rock, the drill is strongly displaced from its initial position.
There is an opinion that when plastering a shell rock, it is necessary to first strengthen a steel mesh on it, but this is not so - the plaster layer will be well fixed on the stone even without using a mesh. The main thing is to apply a spray before applying the base coat, in order to create an initial rough layer.
In wet rooms, only cement-sand plaster is used, and for drier rooms, you can also take gypsum plaster. Before calculating the cost-effectiveness of choosing between gypsum and cement-sand plaster, it is necessary to take into account the thickness of the future plaster layer.
If the thickness of the plaster is small (up to 2 cm), it is more profitable to use gypsum machine plaster. If the layer thickness reaches 3-4 cm (or more), then the cost of gypsum plaster will outweigh the benefit of cheaper work compared to ordinary cement-sand plaster, which is applied by hand.
If your choice fell on machine-made gypsum plaster, do not forget that such material will be beneficial only for large amounts of work - 200 sq. meters of walls or more. At the same time, it must also be remembered that the main part of the models of installations for plastering walls works only from the network. three-phase voltage.
The surface of natural shell rock is beautiful in its own way - it has an interesting texture and a pleasant warm color. Therefore, as a finish, you can use an open cladding with this stone. Especially organically, the shell rock finish will fit into the interior, where there are wooden or made of other natural materials elements.
Most building materials are transformed from raw materials into marketable products after several stages of processing. Clay bricks are molded and fired in a kiln, while aerated concrete goes through a cycle of kneading, autoclave curing and cutting. The cinder block is formed from mineral filler and cement mortar.
The only material that nature has given us completely “ready to use” is shell rock.
It is a conglomerate consisting of shells of mollusks that lived in ancient seas. Accumulating at the bottom, the calcareous shells over millions of years have turned into a durable stone, which a person can only cut into blocks of the desired size.
Large deposits of limestone shell rock are located in the Crimea, Dagestan, Kazakhstan, Azerbaijan, and Moldova. This material is obtained open way without high energy consumption. Therefore, the selling price of blocks in a quarry is very low. As you move away from the deposit, the shell rock becomes more expensive (transportation costs are added to the cost of the material).
The extraction of shell rock is carried out in several stages. First, earth-moving equipment releases from the soil and levels the shell massif. After that, a machine with a huge cutter is installed on the site, which slowly moves along the rails and cuts the layers of the desired thickness. Having cut a multi-meter "pie" from shells into blocks, they are put into vehicles and taken to the buyer.
The answer to the question where shell rock is used is obvious. This material is intended for laying exterior walls and internal partitions residential buildings, construction of outbuildings, garages, basements and fences.
The high decorative qualities of shell rock allow it to be used in landscape design for the construction of retaining walls, grottoes and fountains.
In addition to wall blocks, shell rock tiles are used in construction. For outer cladding it is polished and treated with water-repellent compounds (hydrophobising). Indoors for walls, floors and stairs use sawn tiles.
The main characteristics of shell rock
The density of shell blocks depends on the deposit and ranges from 800 to 2300 kg/m3. The lower limit of the density of the material corresponds to freshly sawn wood, and the upper one brings it closer to concrete.
The density of shell rock is directly related to its weight and strength. Block standard size(380x180x180mm), sawn from light shell rock, weighs about 10 kg. The mass of masonry stone from the densest array reaches 25 kg.
According to the level of strength, the shell rock is divided into three grades (M15, M25 and M35).
The lightweight block (compressive strength 15 kg/cm2) is optimally suited for masonry walls of one-story residential buildings, garages and outbuildings. Grade 25 is most often used for construction two-storey houses. The most durable and heaviest shell rock (grade 35) goes to the walls of basements and basement parts of foundations.
An example of the appearance of the M25 block
Since according to appearance blocks of brands M15 and M35 are often difficult to distinguish, then the manufacturers themselves recommend testing them for strength simple method. Picking up a block and throwing it on a hard surface, look at the result. Durable shell rock grade 35 does not break with such an impact, and less dense material grade 15 with a high content of sand falls apart into several pieces. The most accurate and reliable method for determining strength is testing in a construction laboratory. To remove all doubts, you need to transfer several blocks from the purchased lot to the specialists.
The level of frost resistance of shell rock blocks is very high (50-60 cycles). In this regard, they are not inferior to ceramic bricks and are almost 2 times superior to gas and foam concrete.
The water absorption of this porous material is high (up to 17% by volume). Therefore, without exterior plaster, brick cladding or installing a ventilated facade, this material will pull dampness into the house.
The heat resistance of shell rock is low (at the level of aerated concrete), therefore it is impossible to lay stoves, fireboxes and chimneys from it.
Advantages and disadvantages
Environmental friendliness is the main plus of this material. Extracted from sea bottom sediments, it does not contain chemical substances and heavy metal impurities. However, this advantage can be easily lost by insulating a shell rock house with foam plastic.
This material has one dimensional standard - 380x180x180 mm. Unfortunately, this value is more theoretical than practical, since the actual sizes of shell blocks "walk" within 2-3 cm. For this reason, builders do not really like to work with shell rock, preferring even aerated concrete blocks. Consumption of plaster mortar for finishing porous and not too flat wall significantly higher than that of ordinary bricks and cinder blocks.
The dimensions of the shell tiles differ from the standard masonry blocks and are 35x17 cm with a thickness of 2 to 3 cm. For its production, the most dense and durable material of the M35 brand is used.
Popular with developers in the southern regions of Russia, the Crimean shell stone, when delivered to the central and northern regions of the country, rises in price significantly (2-2.5 times). It levels out important advantage this material is low cost.
Shell rock of low grades (15-25) is a fragile material, so the percentage of damage during transportation is quite high. Despite this, you can avoid excess losses and buy quality material. To do this, you need to personally visit loading area seller and inspect the batch of purchased material.
The approximate price for 1 block in the central region of Russia is from 70 to 80 rubles. For comparison, let's say that in the Crimea this material is sold at 25-30 rubles per block.
If we compare the price of a shell rock with the cost of gas silicate blocks, we will get the following result. 72 blocks are placed in 1 m3. With an average price of 75 rubles per piece, we get the cost of a cube of 5400 rubles, which is significantly more expensive than the price of gas silicate blocks (2700-4500 rubles / m3).
Price facing tiles from shell rock depends on the deposit and the distance of transportation. The lower price limit is 700 rubles, and the upper one rises to 1200 rubles/m2.
At all times, builders have dreamed of the ideal building material, which has no disadvantages. Whether it will ever be found is unknown, but many people who buy an individual residential building project prefer environmentally friendly materials, such as shell rock, whose popularity is growing every year.
At all times, builders have dreamed of an ideal building material that has no flaws. Whether it will ever be found is unknown, but many people who buy an individual residential building project prefer environmentally friendly materials, such as shell rock, whose popularity is growing every year.
This limestone consists of the shells of marine animals and their remains. He is characterized by:
- macroporosity (21-60%);
- volume weight 1100-2200 kg/m3;
- thermal conductivity is 0.3-0.9 W / (m-K);
- in compression, the ultimate strength reaches 0.5-28 mN/m2.
In the old days, it was quite common and was called "shell rock", "shell", and its dense rocks are known as marble and limestone. The stone is "warm", light, has excellent sound insulation. It is not difficult to process: rectangular blocks are cut out of a large array, which are the building material.
Advantages of a shell rock
Experts divide the shell rock by color and density into two groups: white - more dense, and yellow - less dense. Regardless of where the stone is mined, chemical composition he has the same. Positive traits shell rock are.
- High thermal insulation. The reason for this property is the porosity of the stone: the pore volume is in the range of 21-60%. Walls made of shell rock, due to their porosity, retain heat for a long time in cold weather, and coolness in hot weather.
- Environmental Safety.
- High vapor permeability makes the house dry. The moisture that has appeared is simply forced out through the shell rock, which, although it gets wet, dries out very quickly.
- Doesn't rot.
- Excellent soundproofing.
- The small weight of the stone is also due to the high porosity. The marking of the shell rock used in construction goes from the most durable M35 to the least durable M15. However, it should be remembered that the more visible the pores, the stronger the material.
- The low price of the shell rock is its very big plus. If you decide to order a residential building project, then its construction from shell rock will cost much less than any masonry material. True, immediately inquire where it is mined, since if the material is transported from afar, the price will be higher.
Negative properties of shell rock
The first problem lies again in the porosity of the material, it is correct to say - in heterogeneity. After all, different deposits have different layers, and, consequently, different porosity.
You have decided to buy a project of a country house, which provides for the construction of a residential building from shell rock, you start construction, and a batch of material - with different indicators. In this case, you need to contact only specialists and together with them choose a stone with approximately the same data.
The biggest disadvantage of shell rock is through pores, which greatly reduce the heat-insulating functions. You will have to check each block visually and weigh it - a quality stone M25, M35 has a weight of approximately 16-17 kg. M10, M15, M20 - does not exceed 12 kg.
The second problem is high water absorption. To prevent the walls from “filling up” with water, they need to be covered with special solutions that repel moisture. Outside, a ventilated facade, preferably a wooden one, can solve the problem.
A less dense shell rock crumbles during loading, transportation and unloading, the edges are rounded. Masonry at uneven surface stone will require more mortar.
Use in construction
Having considered all the positive and negative characteristics of the shell rock, it should be noted that it is used quite widely in construction. What exactly cannot be built from it is fireplaces or stoves. Most often it is used for:
- erection of walls and partitions;
- wall insulation;
- lining;
- decoration;
- construction of fences and barriers;
- implementation of landscape projects.
Builders even use shell chips, adding it to concrete. Simple stone processing allows you to build chic arches, cornices, front entrances.
Construction features
When buying individual ones that will be built from shell rock, pay attention to the block size - 20:20:40 cm. Laying a wall in half a block will require 18 pieces per 1 m2, in a whole block - 28 pieces. Any foundation, depending on the type of soil, although for greater certainty it is better to make a monolithic reinforced concrete.
Ceilings on the walls can also be put on any: metal or reinforced concrete, but most often, solely for environmental reasons, wooden beams are used.
Processing shell rock is very easy. Its porous structure allows sawing the block with any saw, including a hand saw.
Shell rock - natural stone, which has many positive properties, although there are problems, fortunately, solvable. But consider some more facts:
- this is the only stone that completely cuts off radiation;
- rodents do not like this stone;
- it also fills the air with iodine.
Builders of most countries of the world consider shell rock to be the undisputed leader in the construction of eco-houses.
