Mauerlat is mounted to aerated concrete or foam concrete, as a rule, by means of a reinforcing belt located in the upper part of wall structures. It is he who becomes the support for the Mauerlat and provides great strength to the whole house.
What is Armopoyas for?
As you know, aerated concrete is characterized by high sensitivity to local loads. That is, when the allowable pressure of the drill used to create holes in the block is exceeded, it is likely that it will become cracked or crack at all. To prevent such changes, an arm belt is set up, and it also avoids the sliding and deformation of blocks, which leads to uneven pressure of the total weight.
What you need to know
The functions of the Mauerlat are to connect the building box and the rafter system, as well as to share the load with the roof structure along all the walls. For the manufacture of fasteners, mainly wood is used. The best option is a hardwood beam, the surface of which is covered with an antiseptic composition.
It is advisable that the fastening of the Mauerlat to the wall of aerated concrete be continuous around the perimeter of the wall structures. To fix individual elements, a direct lock of a suitable size is used. To ensure rigidity, nails are driven in, as a result, the bars form a single system for the installation of rafters, connected with neighboring elements. The bars should be located on the inside of the masonry, with at least 5-6 cm to the outside. To support the Mauerlat, a brick parapet is made along the outer edge of the wall, individual parts of which are fastened with a direct lock.
Methods for attaching Mauerlat to aerated concrete walls
It is possible to use several techniques suitable for various conditions:
- fixing with studs mounted in masonry;
- Anchor anchoring based on armopoyas;
- Mauerlat mounting to aerated concrete wire.
In the latter version, the wire is laid between the bricks so that the middle part is located under them, and the outer sides are outside. The length should be sufficient for free threading through the beam and subsequent tightening. The number of strands should correspond to the number of rafters. Using a metal wire, the Mauerlat is then fixed to the wall.
Reinforced belt
Mounting Mauerlat to aerated concrete with an arm belt is the most preferable, since the blocks are not dense enough in structure and it is difficult to mount any type of clamps. It is worth noting the benefits of using a reinforced belt. First of all, it is the alignment of the upper part of the walls and the strengthening of the entire structure of the house, with its arrangement, clamps for Mauerlat are created in advance. In the design, the easiest way is to use U-shaped block elements in the form of a gutter around the perimeter of wall external structures, while there should be no interruptions. Next, a cut is formed on the corner parts. To assemble the frame, reinforcement with transverse jumpers is used, then it is laid in the gutter, followed by pouring concrete mixture. To ensure solidity, the mass is poured in one go. Before this, an anchor with a wire is fixed on a reinforced belt. Of particular importance is the careful compliance with the level. The studs are also fixed on the frame along the line in accordance with the tensioned cord, in a vertical arrangement. Just as in the case of using steel wire, the number of rafter legs and anchor clips should match. It is necessary to first determine the optimal location of the elements in order to avoid coincidence with the places of fixation of the rafters.
Mounting Mauerlat to aerated concrete using studs
This option is optimal for small buildings and roofs that have a lightweight structure when there are no significant loads on the roof and walls. There are two types of hairpins: these are bolts forming a single structure with a steel square, or elements in the form of a L-shaped. Their fastening is carried out during the laying of the blocks in several rows to the top, while the length should be enough for the locknut and the thickness of the bars. The process is similar to the anchor method: the beam is put on the studs when the masonry solidifies and fixed with nuts. There are also other ways of attaching Mauerlat to aerated concrete, but they are used less often because of less reliability.
Sufficient rigidity and reliability of fastening is formed due to the binding of bolts to the frame and their additional bricking with concrete. It is enough to put the Mauerlat on the studs and with the help of nuts tighten to the blocks.
If it is necessary to mount the Mauerlat to aerated concrete without armored belts, monolithic plugs and pillows in the walls are used. Their dimensions should be within 400 mm, they are recesses with a structure of reinforcement of small thickness or metal bars, and anchors are fixed on it.
Features
The use of anchors and studs requires the prior creation of holes. A number of difficulties may arise here. For example, fasteners may not be smooth enough, even if the cord and level are used, it is most difficult to work with liquid concrete. First of all, the exact location of the fasteners is set, the points of the upper parts of the bolts are marked on a board with a flat surface, then they are transferred to the Mauerlat, in which the corresponding holes are drilled. Next, the beam is fixed to the wall. The base of the rafters is fixed on bolts, washers and nuts are additionally used.
Mauerlat should be fastened to aerated concrete after selecting the fixing method and preliminary planning of the number and location of the retainers. First of all, reliable insulation is formed between concrete and wood. This is necessary due to the development of intensive rotting of the tree, to prevent this process, a material for waterproofing, laid in two layers, is used. As it can be both modern options, and familiar, such as polyethylene or roofing material.
When using wire, it is enough to make holes at a distance of no more than 35 cm for all fasteners, thread the wire, while the ends are twisted so as to obtain the maximum connection between the wall and the Mauerlat.
It should be noted that saw blades should not be used with a grinder, as this tool is not suitable for wood. Failure to comply with this rule may result in personal injury during use.
Sliding pairing
The rafters are mounted after tightly securing the Mauerlat. The rafter structure can be hinged or rigidly fixed, the selection of a suitable option depends on the requirements that the Mauerlat attachment points to aerated concrete must meet, the general configuration and type of structure (hanging or layered).
The hinged version may have a different pairing. The most common is the mount with rigid pairing, while there is no possibility of displacement and rotation. Sliding mating is also used, providing beam movement and rotation in relation to the beam. The latter option reduces the expansion of wood caused by temperature and shrinkage of the building; all this prevents the transfer of bursting loads on the wall structure.
To create a sliding pairing, three methods are used:
- the use of a special metal fastener for connecting rafters;
- bringing the beam out of the walls and fixing it with a plate;
- creating a gash in the rafters board and installing it on a Mauerlat using a corner, brackets or nails.
Hard pairing
Concrete and wooden buildings, as well as timber structures, are rarely dispensed with without it. Due to the fact that both frame and wood houses are notable for shrinkage, in the absence of the possibility of simultaneous displacement of the building’s box and roof, there is the possibility of significant stress causing damage to the walls and rafters. To create a rigid interface, support bars with a length of 1 meter are required, fixed on rafters, nails and steel corners. The rafter with a beam should abut the Mauerlat structure in accordance with the pressure line. This prevents perpendicular displacements. Corners and nails eliminate lateral displacement, while the latter should be driven in at an angle on both sides, so that they intersect in the beam. A third nail is driven through the beam, which should have a vertical direction.
Conclusion
The fastening of the Mauerlat to aerated concrete has its own characteristic features that must be taken into account when installing, so that problems with the operation of the roof can be prevented. In the absence of experience and relevant knowledge for the creation of the project and the subsequent installation of the rafter system, it is advisable to turn to professionals who guarantee a reliable roof that will protect the house from cold and rain for many years. During construction, you should not save at this stage of work, as this can cause additional financial investments and time costs.