The reliability and quality of brickwork depend on the thickness of the seams between the products. This value is laid down at the stage of drafting the project and must be controlled in each row. It is necessary to check this parameter by measuring the height every 5-6 rows.
Why you should follow the rules
If the recommended values are not met, this will indicate an overspending of the solution, the formation of weak bonds and the rapid destruction of the building in the future. The decrease in strength is due to the occurrence of compressive and bending loads. This factor is also due to the uneven release of excess moisture from the connecting mixtures. This cannot be considered acceptable.
Requirements of SNIP for the thickness of the seam
The thickness of the joints in brickwork is on average 10 mm. The final value is selected depending on the design and type of products used. At largedownward deviations, it is not possible to compensate for the unevenness of the products, and the calculated number of blocks may not be enough. If you increase the mentioned value, then the walls will lose strength for the reasons mentioned above.
The mentioned parameters are used in the construction of load-bearing walls. For masonry, the thickness of the horizontal joints is maintained at 12 mm. Vertical joints are usually 10 mm. The limit in the longitudinal rows varies from 10 to 15. In the transverse rows - from 8 to 12. If certain values are prescribed by the project, then deviation from them is unacceptable, therefore, in the process of work, it is necessary to monitor and verify.
Expert Tips
The thickness of the seams in brickwork is influenced by several factors. This is the professionalism of the masons, the chosen technology and the stiffness of the solution, as well as the climatic conditions during the work and subsequent operation. As for the chosen technology of mortar stiffness, during laying bricks can be placed in a clamp, which requires high-strength cement-sand mixtures. The thickness of the seam is the maximum possible - 12 mm.
If plastic and liquid compounds are used, then the bricks are laid end to end and with trimming, that is, as closely as possible. The step between adjacent products should not be more than 10 mm. The thickness of the joints in the brickwork is made smaller if the work is carried out in winter. At the same time, antifreeze agents are added to the mixtures, and the seams are heated after laying the products. This also applies to the walls that are built in northern latitudes.
Masonry is doneas monolithic as possible to reduce the effect of low temperatures. Thickness can be affected by shapes and geometric dimensional accuracy. If we compare it with aerated concrete blocks that are laid on building glue (the joint thickness is 3 cm), then it is more difficult to install a brick, because you have to correct deviations from the normative and declared values. Elements can be varied and cheap, forcing specialists to change the thickness of the joints by 12 mm to fit the design data.
What else is important to know
The last factor in choosing the thickness of the joints in brickwork is usually decisive. Professionals can correct products with irregular shapes and sizes, and with large deviations, the final strength of the structure can be reduced by up to 25%. To resolve the issue, reinforcement helps little, and the material must be well tested at the stage of purchase.
The reliability of masonry, in addition to the thickness of the mortar, is influenced by the strength grade. It is important to take into account frost resistance, the proportion of voids along with geometric accuracy. This thickness of the horizontal brickwork joint is true for all small-piece elements, including facing and silicate.
Increasing the thickness is slightly permissible when working with double varieties, but when erecting load-bearing walls and performing front masonry, the layer in relation to the vertical seam must be kept within 10 mm; as for the longitudinal, this value is 12 mm. As an exception, high-temperature furnacesheating appliances and similar structures made of refractory products. About 5 mm of solution should be left between them. A separate group should include rectangular tiles. It is laid in compliance with the recommended jointing norm. It depends on the type of edge of the products and the texture, as well as the requirements for moisture protection.
The thickness of the seam between facing bricks
The thickness of the seam in facing brickwork is 12 mm. In order for the wall to breathe better, every fourth vertical seam must be filled with mortar. On sale you can find special spacers-crosses used for brickwork. With their help, you will be able to form the same thickness of the seams.
Gaskets are installed between adjacent bricks and allow you to adjust the distance between products. Remove the spacers before grouting the outside seams. Thus, the thickness of the seam in the brickwork of facing bricks is the same as in the case of ordinary bricks.
Basic types of seams
Depending on the subsequent finishing and installation method, there are three types of seams:
- waste;
- raised seam;
- concave seam.
If the wall is supposed to be plastered, then for better connection with the finishing layer, the seams from the side of the front surface should not be filled with mortar 15 mm deep. Such masonry is called wasteland. If athe solution reaches the front surface, then the laying is performed in pruning. Excess mixture is squeezed out with a brick on the face and trimmed with a trowel. They can be smoothed out with stitching.
Depending on the type of jointing, it is possible to distinguish a convex and concave seam. This method is used when laying on a single-row dressing system. But to facilitate the work, a certain algorithm should be used. After laying the bonder bricks, the spoon bricks are laid, then the inner versts and the filling of the wall go. If you follow this sequence, then you will not have to switch from outer to inner versts as often as when laying, which involves the installation of one row, and then another.
Methods of laying bricks
Now you know the average thickness of the horizontal joints in brickwork. However, for a good result, it is important to ask about the methods of work. The choice of this or that method is subject to several factors, among them:
- season;
- plasticity of the solution;
- appearance of the front surface.
The press-on method is used for both spoon and bond stitches. This technology is applicable in conjunction with rigid solutions with full filling. About 10 mm must be maintained from the edge of the mortar bed of the front wall. There is 1 more method - back to back. Another name for it is in the wasteland. In this case, the facial seams are not completely filled. Plastic solutions are applicable here. With this method, the filling will be incomplete, and the step from the verticalplane will be equal to 30 mm.
You can also apply the butt method with trimming. At the same time, the solution spreads, as for the clamping methods, and masonry work is carried out as if using the butt technology. The solution must be hard, and trimming is carried out by trapping the extruded solution with a trowel. Excess mixture is thrown into the next section. This type of masonry is more economical in terms of the consumption of related materials.
For backfilling, the semi-addition method is used. First, the outer rows are laid, and the work will have to be done with both hands. At the same time, it will be necessary to take two bricks and bring them flat at a distance of 8 cm from the previously laid product.
Masonry mortars
What thickness of the seam in the brickwork should be, you now know. But for independent work, it is important to ask about the types of solutions. Among others, lime mixtures should be distinguished. If you need a more plastic composition for installing interior partitions or installing fences, this mixture is the best fit. The basis will be sand, as well as quicklime. The components are mixed until a homogeneous mass is obtained, to which water is then added. Such a solution should not have impurities and lumps. For one part of lime, from 2 to 5 parts of sand of medium fraction will be enough.
The most common is a cement mortar, which is prepared from the ingredient of the same name and sand. The proportions can be very different and depend on the brand of cement. So, from 3 to 6 parts of sand can be added to a part of cement. First, a dry mixture is kneaded, to which water is gradually added. Everything is mixed until a homogeneous thick mass. The mortar may be stiff, too stiff, or too strong.
The mortar can be complex, in this case it consists of lime, cement and clay. Cement and other components can be added to lime. Clay is added to make the composition more plastic. It does not fall apart during operation and fits easily. After reviewing the thickness of the seam in the brickwork for the furnace or the walls of a residential building, you must decide what kind of mixture will be used for such work.
In closing
In order for the building to be durable, you must comply with SNiP 3.03.01-87. These documents are valid for the construction of stone and brick walls. After reviewing the information, you will be able to learn how to lay with whole bricks and stones of all kinds.
