Most often, monolithic concrete foundations are poured under suburban low-rise buildings. However, sometimes a brick is also used to assemble the base of the house. The choice of this material in most cases is determined by the fact that it is possible to erect a very attractive design from the point of view of aesthetics from it.
The advantage of using bricks
The estimated service life of foundations erected from this material is lower than that of monolithic ones. However, it has been observed that in practice it usually happens the other way around. If the concrete strip of the building is able to reliably protect the walls of the house from destruction for 200-300 years, then the service life of the brick foundation often exceeds 400. But of course, such a construction will be strong and durable only if the construction technology is strictly observed. Further in the article, we will consider how to lay out the foundation of brick with your own hands correctly.
In which cases, instead of concrete, you can use a brick
The foundations of houses of this type are being erected mainly on dry non-porous soils. It is also desirable that the groundwater level at the construction site be as low as possible. On not very stable soils made of bricks, the foundation may be assembled only with preliminary pouring of a concrete “cushion” and mandatory reinforcement. With a high occurrence of groundwater, special compounds are added to the masonry mortar that increase its waterproofing properties. Otherwise, such a base will quickly collapse due to high humidity.
For houses above three floors of brick, the foundation is not allowed to be erected by building codes. In case of emergency, the assembly of a reinforced powerful base of this variety is allowed. However, in this case, the foundation is unreasonably expensive. Therefore, in practice, monolithic concrete foundations are usually erected for buildings from 3 floors.
Among other things, structures of this type are most often assembled under the walls of buildings made of light materials. For example, a very good solution would be to build a brick foundation for a log house. Very well, this option is also suitable for block, panel houses or for walls made of foam concrete. Under brick or monolithic structures, such bases are not suitable. In this case, it is also advisable to build a monolithic reinforced concrete structure.
The regulations allow such bases to be used not only for residential buildings, but also for any other structures. Very often, for example, a brick foundation is built for a bathhouse, a gazebo, a garage. The technology for assembling such a base for structures for various purposes is almost the same.
How to choose a material
There are many varieties of bricks in the modern market. However, not all types of this material can be used for the construction of foundations. Only red ceramic brick is suitable for this purpose, and even then not everyone. The indicators of the stone intended for the construction of the foundation of the house should be as follows:
brand strength not less than 150;
frost resistance from 35 cycles;
density not less than 1600 kg / m 3 ;
water absorption - 6-16%.
In the people, a material that meets all these requirements is called iron brick. When choosing such a stone, you should pay attention, including its appearance. The crimson color of the brick suggests that it is not sufficiently burned, and therefore not too durable and moisture resistant. The concave or convex edges of the stone, on the contrary, indicate that it was kept in the furnace for too long. Such a brick is fragile. To build the foundation of the house is possible only from the highest quality material. Therefore, among other things, when buying a stone, you should pay attention to the reputation of the supplier and manufacturer.
Sometimes the owners of suburban areas, the foundation itself (its underground part) is assembled from red iron ore, and the base is made of silicate brick. To do so with building codes is allowed. But only in the most extreme case - on dry soils and during the construction of some insignificant buildings (summer kitchens, garages, sheds, utility units, etc.).
How to dig a trench
So how do you build a foundation of brick with your own hands? Step-by-step assembly instructions for this structure will be presented below in detail in the article. However, first you still need to figure out what the trench should be for this structure, as well as how to properly carry out the preparatory work.
Only columnar or tape foundations of houses are allowed to be erected from stone by building codes. Unfinished brick foundations are not assembled from bricks. The sole of this design in any case should be located below the level of freezing of the soil. For the southern regions of the country, this figure is 0.6-1 m, for the northern regions it can reach up to 2.5 m. Exact numbers can be found in special directories.
Trenches under the brick foundation will have to be excavated not only deep, but also wide. Indeed, in this case, you need to make sure that the bricklayer has enough free space to do the masonry. After erecting a foundation from a brick, this "extra" space is filled with expanded clay or light soil. This allows you to reduce the indicator of the level of freezing for this particular place, as well as to minimize the negative impact on the underground parts of the structure during spring heaving.
In the rest, trenches under such a foundation are excavated according to the same rules as under the usual monolithic. That is, marking is preliminarily performed using pegs and a cord (according to the "Egyptian triangle" or "two curves" method), and then excavation work is carried out.
Preparation of masonry mortar
The quality of the brick foundation is subject to increased requirements. After all, the service life of the entire building depends on how reliable it is. Therefore, it is responsible to approach not only the choice of the stone itself, but also the procedure for preparing the solution. Sand before kneading must be sieved. Lime in a solution intended for laying the foundation, in no case add. It is necessary to prepare the mixture using a concrete mixer. The more uniform the composition, the better.
The construction of the strip foundation: preparatory work
In a dug under the base of the house, the trench is first carefully compacted and the bottom leveled. Then a sand-gravel mixture with a thickness of 15 cm is poured onto it. The resulting “pillow” is carefully compacted with a tamper and water. Then equip the waterproofing layer. To prevent the soles of the foundation from getting wet during operation, a ruberoid (2-3 layers) is rolled out on a “pillow”. Simultaneously with the bottom waterproofing, it is desirable to equip the side. To do this, additional strips of roofing material are glued to the canvas on both sides using bitumen mastic.
Mortar support device
On soft soils made of brick, the foundation, as already mentioned, is being erected with a preliminary arrangement of a reinforced concrete “pillow”. The latter is poured into a wooden formwork with a reinforcing frame, assembled from a 12 mm rod. The thickness of the “pillow” should be at least 10 cm. Before you begin assembling the pillars, you need to withstand it for two weeks.
Assembly of the strip foundation
The first row of bricks is laid directly on concrete or roofing material, taking into account the subsequent dressing and filling the vertical joints with mortar. Next, the foundation is assembled according to general rules with mandatory reinforcement, vertical and horizontal. To build the base of the house from brick is possible only with a single-row dressing of seams. In order to reduce the adhesion of the walls of the structure to the ground, flashing is performed (flush). Seams are not treated only if in the subsequent walls of the structure it is supposed to be plastered for additional waterproofing.
Reliable do-it-yourself brick pillar foundation: step-by-step instructions
In this case, not holes are dug under the base, as when using concrete mortar, as well as trenches. After all, for the laying of the pillars, the bricklayer needs a place. You need to install supports under all the bearing walls of the building. Mandatory posts should be laid out on the corners. They also need to be installed at the intersection of the walls. The minimum side length of a column of a square section is 380 mm (1.5 bricks). Above the ground, the support should rise at least 20 cm.
In order for the masonry to turn out to be even, first the box templates knocked down from the boards are installed in the trench. Under them, waterproofing is pre-laid and concrete platforms are poured.
Masonry lead around these patterns. After several rows are laid out, the box is taken out. As a result, an empty space remains inside the column that needs to be filled with concrete. Next, the masonry is carried out, constantly leveling the bricks to the desired height. Reinforcement (three rods of 12 mm each) is inserted into the empty space remaining in the center of the posts and the solution is poured.
Above ground, finished poles are often joined with concrete tape. It is poured in the formwork with reinforcement. It is impossible to connect its parts with each other and with poles. Instead of concrete, the space between the pillars can also be easily laid with bricks.
Brick foundation for a bath
The principle of building the foundation for such a structure is the same as for a residential building. Most often, a do-it-yourself brick foundation for a bath is poured in the form of a continuous tape. However, if the walls are supposed to be made of shield, you can save and get by with a columnar base. For the basement of the strip foundation of the bath, it is better to use red brick. Silicate is afraid of moisture. Also, when arranging the base under the walls of the bath, maximum attention should be paid to waterproofing.
How to make a brick foundation with your own hands for a gazebo
In this case, it will be enough to erect four columns at the corners of the structure. Under very light arbors, such foundations are sometimes not even buried. For large structures of this type, 6-8 supports are installed.
Like the strip foundation made of brick for a bath, the base under the arbor should be waterproofed. Under the supports, roofing material in several layers is necessarily laid. When pouring the empty central part of the posts, pins or rods are installed under the harness and arbor frame racks. Above the surface of the support they should rise by 20 cm. The rods are also deepened into concrete by 20 cm.