The construction industry is constantly replenished with new high-tech materials, ideas and technologies for building construction, but the traditional concept of the eco-house still remains relevant. Such facilities attract fundamentally important advantages, including minimal financial investments and environmental safety. One of the most affordable and common methods of construction in this direction is the device of a house made of clay and straw. A photo of the finished structure of this kind is presented below.
The advantages of clay and straw houses
In addition to modest monetary investments in the construction of an eco-house and the naturalness of materials, a whole series of its technical and operational advantages can be distinguished:
- Thermal insulation. The clay structure has a good insulating function, quickly warming up and for a long time retaining thermal energy indoors.
- Soundproofing. Another advantage associated with the insulating properties of clay.
- Durability. With careful use, such houses can stand for about 50 years without losing their basic protective properties.
- The ability to communicate. In the course of building a house of clay and straw with your own hands, you can make a channel of any configuration for future laying of a cable or pipeline. The flexibility and flexibility of the material opens up almost limitless possibilities in the engineering equipment of the structure.
- Fire resistance. One of the rare cases when natural building materials without special protection and additives can withstand fire.
The technology can also be considered as a worthy alternative to modular construction in terms of an optimized approach to the direct construction of a building. Even without the help of specialists and professional equipment, such an object can be implemented in the shortest possible time.
Disadvantages of clay and straw houses
Despite their longevity, these are not the strongest houses, even compared to today's popular frame constructions with a modular design. Much depends on the quality of construction, but homemade clay as such cannot compete with either brick or foam block in terms of strength. On the other hand, the lightness of clay and straw houses makes them more resistant to dynamic loads, so from the point of view of earthquake resistance this is not a bad housing option. As for the weak points of this type of ecohouse, without a regular biological treatment, the risk of developing fungus, mold and bacteria indoors will always remain.
Creating a house project
The clay structures have a fairly simple layout, they have few rooms, there is no attic and technical rooms. Therefore, the creation of a technical plan can be reduced to a sketch on paper in the form of a drawing. It should outline the geometry of the premises, the lines of walls and partitions, the shape of the facade and the parameters of the corridors. Based on the prepared project of a house made of clay and straw, a calculation is made according to the volume of building materials. It is important to consider that the work will require not only clay with straw, but also sand, gravel (or gravel), reinforcement elements, lumber and communication consumables.
Clay selection for home
A fundamentally important point, since clay will be laid in the foundation of the frame and the entire load will be on it. In some regions, this material can be mined free of charge right at the site of future house construction. This is possible if a sufficient clay content is present in the soil as such. To find out whether a particular material is suitable for construction, the following test will help:
- Clay samples are made with its removal from the pits, removed from each other at a distance of 10-15 m. Usually take up to 10 samples.
- About 3 g of salt is diluted in 3 l of water. The finished solution is poured into cans.
- One jar of clay is placed in each jar.
- At intervals of 30-40 minutes. shake each jar several times.
The process of separation of the ingredients of the composition will follow. Already by its signs, it is possible to determine whether a house made of clay and straw will be durable, if this composition is used. In the process of softening the samples, three groups of ingredients will be separated - sand, garbage in the form of grass and various organics, and clay itself. The sand should settle, and the clay should stay afloat. If in the end, a layer with a sand fraction is thicker than clay material, then a specific sample is suitable for construction.
The technology of creating a clay mixture
On the basis of clay, a full-fledged mortar is made, but unlike cement mixtures, it will be used precisely as raw materials for blocks. As already noted, you can use traditional ingredients with gravel or gravel, or you can limit yourself to a minimal set of components for building a house of clay and straw. The technology of manufacturing the solution involves the use of 1 part clay, 0.5 part straw and 2 parts sand. There are no strict standards for water, since the volume will depend on the structure of a particular clay variety. That is, it will be necessary to select a ratio by eye, so that it turns out not a liquid, but not a dry, friable mixture. Stir the ingredients with a stirrer after thoroughly softening.
Building Block Formation
Clay blocks are made from the prepared solution. Without special equipment, the simplest devices can be made in the open air - of course, it is advisable to do this on warm days under the bright sun. Initially, a lathing structure is made of timber and planks with cells of 20x40 cm and a height of about 20 cm. A solid sheet of plywood can be used as a substrate. At this stage, it is worth answering the question of how to build a house of clay and straw so that it has even geometry and a minimum of gaps with cold bridges? The quality of the frame largely depends on how correct the shape of the blocks is. If they allow you to build smooth and dense walls, then an adequate margin of safety and thermal insulation effect will be achieved. Each cell is neatly filled with solution. The full hardening time can vary from several days to a month - it depends both on the properties of the solution and on climatic conditions. During periods of rain or wind, the structure is covered with polyethylene or roofing material.
Foundation building
To begin with, it is worth deciding on the choice of a site for construction, since not on each soil, in principle, the construction of such buildings is allowed. The surface must be reliable, earthquake-resistant and with a low groundwater level.
Directly to the foundation of the foundation can be approached in different ways. Simple technology, which is mainly used in African villages, involves the use of stone blocks as a bearing part. But if there are all the necessary components for creating a cement mortar, then there is no point in abandoning the strip foundation. In both cases, a perimeter trench will be required (contours of external walls) of a depth of about 50 cm. If you plan to build a house of clay and straw on a stone base, the bottom of the trench should be covered with a drainage pillow. There sand is filled with gravel and soil. Only after this stones are evenly stacked, which, however, will also be useful to fasten with one or another mortar. The grillage in this case is made of large logs or beams. In the case of a strip foundation, it will be necessary to form a reinforcing frame in a trench, after which arrange a wooden formwork and fill the mold with concrete.
Wall frame construction
The key difference between clay and straw walls and a brick house is that a wooden profile is used instead of cement mortar. At the joints, starting from the level of the grillage, intermediate strips are installed. The empty space of the frame is just filled with blocks of clay and straw. The house is strengthened by metal rods that sew structural bars across the entire height and width of the frame. The lower blocks are put on reinforcement fixed in the foundation at a distance of about 100 cm. At the next levels, additional rods are passed.
Home decoration
In order to increase thermal insulation and protect block surfaces, it is worth using an outer coating of fibrous mats. The same straw can also be used for them, but it is better to include stiffer elements like reeds or chestnut trunks in the strata and strata. A house made of clay and straw with such a finish will receive effective insulation and an attractive appearance. In the manufacture of mats used linen twine or aluminum wire. The coating is knitted, which is then either stuccoed or fixed to the crate by blocking it to the facade.
Construction of the roof truss system
The supporting structure for the roofing is made of straight sanded poles. Full-length boards and bars, which are usually used in the rafters of private wooden houses in this case, will not work because of the large weight. The geometry of the slopes is calculated on exposure angles of the order of 40-50 °. As a support for poles, which will be arranged in a circle connecting the walls of the house with corollas, you can use dowels. Poles with a thickness of 6-7 cm are inserted into pre-prepared holes and fastened with nails. To insure the structure, you can additionally use supporting elements from thin boards. Usually they are used for the drying period of a heavy clay roof, and then removed.
Roofing device
Sheaves of 50-70 cm long and 10-15 cm thick are knitted from straw. In this case, spikelets must be cut. Next, each sheaf is aged for several hours in a clay solution with the addition of water. Ready snopiki need to cover the roof frame, completely covering the surface of the rafter system. When making the roof of a house made of clay and straw with your own hands, it is important to correctly calculate the load. Excessive solution content in the sheaves will increase the mass of the structure, which is undesirable. In addition, it is necessary to consider the elements of reinforcing the strapping of the coating using reinforcing elements. Mounting to the ramps can be done using the same wire or thin reinforcing bars with clamps based on clamps. In this case, it is worth abandoning the linen strapping, since in conditions of direct contact with precipitation it does not retain its strength properties for long.
Repair of clay and straw houses
Periodically, the clay house will need to be updated in design, minor repairs and replacement of individual parts. Serious structural replacements are mainly required in relation to the foundations and are reduced to lining with silicate brick, and the rest is cosmetic in nature. For the most part, the restoration of a house outside with clay and straw consists in the coating of damaged areas on the surface. To do this, you can use the same clay mortars, and special compositions for plaster. Preferred is moisture resistant and mechanically resistant primers. Decorative decoration in the form of whitewash or painting will be useful to combine with a practical protective function, using means with an antiseptic effect.
Conclusion
Clay soil construction should not be regarded as an exceptionally cheap technology that justifies itself only in African villages. Improved techniques of such construction are actively used in civilized countries. What is the name of the house made of clay and straw in the language of experts? Such objects are called saman (from the Turkic name for straw). But the main distinguishing feature still relates to the use of clay mixtures in a particular recipe. Today, there are many modifications of this technology, which also allow the use of raw brick, wood-shaving materials, lime, expanded clay filling, etc. The specific technique with the technical nuances of construction is determined by the requirements for housing and the conditions for its future operation, taking into account climatic conditions.