Building your own house or bath inevitably raises hundreds of questions for a beginner, and one of the first among them is the question of the foundation and its reinforcement. The correct answer here is literally fundamental: if the foundation is the basis of the strength of the whole house, then the reinforcement is the key to a reliable foundation. Reinforcement allows several times to increase the resistance of the foundation to the unevenly distributed weight of the house, low temperatures, weathering, painting and other destructive processes. Any mistake here is fraught with the fact that after a few years, such a strong outwardly concrete is covered with cracks, a more or less noticeable deviation of the entire structure from the vertical appears. Therefore, we will consider several of the most important points of reinforcement that should be taken into account already at the stage of preparing the pit.
1. About the difficulties of choice. Rolled metal for reinforcement includes cold-drawn wire from which a frame mesh and hot-rolled rods, corners and channels are woven, and steel with an admixture of chromium, silicon, titanium, manganese is used as a material for them to improve the strength indicators. In private construction, metal rods with a length of 4-6 meters and a diameter of 1 to 4 or more centimeters are most often used as the basis for walls and foundations. The obvious assumption of a beginner is that the thicker the reinforcement, the stronger the structure being erected will be, but in fact there are several subtleties here. First of all, this is a way of attaching reinforcing rods to each other – according to the pros, the best option is to tie them with a specially designed knitting wire. But bonding allows you to firmly connect only rods with a diameter of up to 2-2.5 centimeters, for more massive structures, the only way of fixing is welding. Secondly, in order to achieve maximum stability characteristics, it is not enough to choose just the right diameter; it is also important to ensure that the metal and cement form the most monolithic structure. Therefore, choose reinforcement with the maximum large bonding area – notches, edges and corrugations..
2. Layout of reinforcement. At first glance, the traditional laying scheme for the foundation is quite simple – a frame is created from perpendicularly intersecting rods, the distance between the intersection points is 1.2-1.5 meters, and 3-4 rods fit into each row. Professional builders complement it with a few more important touches. Firstly, under the frame, it is necessary to put a layer of reinforcing mesh, put exactly the same on top, welded it to the rods. Secondly, the distance between the rods should be no more than 20 centimeters, and their “overlap” along the perimeter should be about 60 centimeters. For most wooden and brick cottages, this is enough, but if columns and load-bearing walls are installed in the house, then in the area of their intended location you need to add another layer of reinforcing mesh in order to compensate for the load on the foundation.
3. A few words about saving. Beginners are advised to reduce foundation costs by using relatively cheap scrap metal for reinforcement. And if we are talking about a small building – for example, a summer kitchen or a terrace – then the use of scrap ferrous metals really allows you to reduce the construction cost estimate, and an insignificant load does not create precedents for the appearance of cracks in concrete. In the case of the construction of a country house or a garage, it is worth remembering the requirements for reinforcement – strength, plasticity, absence of corrosion and resistance to it, high adhesion to concrete, the ability to easily recreate the desired scheme. In addition, the metal must be weldable easily. Therefore, if scrap metal meets all these requirements, then its partial use really allows you to reduce construction costs without compromising quality..
Author: Elvira Kurmaeva