Proper fastening of the Mauerlat to aerated concrete - possible options tested in practice. There is no reinforced belt in a house made of aerated concrete. How to attach a roof to aerated concrete

For a user uninitiated in capital construction, it is unlikely that it will be known what a Mauerlat is, what role it plays in the construction of the structure, and so on. Therefore, the question of how the Mauerlat is attached to aerated concrete generally causes misunderstanding.

However, the use of such technology is a relevant and very effective solution. With its help, you can solve a number of significant problems that can reduce the durability and strength of the structure.

It is also necessary to mention more economical option implementation of the specified fastening method. If it is necessary to fasten the Mauerlat to aerated concrete without an armored belt, then in this case it is not a continuous armored belt that is poured, but concrete pads are made in the right places. This type of fastening for foam blocks is also quite reliable.

2.3 Metal studs

In the presence of small house, as well as a little pressure from the roof, to fasten the cinder block walls to the Mauerlat beam, you can use a lightweight method - metal pins embedded in the wall. These are steel fasteners in the form of bolts with a base in the form of a square with sides more than 5 cm.

If, when laying cinder blocks, studs are embedded in the wall, they must be installed one or two rows before the top edge. The length of the pin should be sufficient to pass through the beam.

Subsequent commit similar to fastening a Mauerlat with a cinder block using anchor bolts.

2.4 Waterproofing during installation

Having decided on the method of fastening, it is necessary to calculate the fastening elements and their location. If it is necessary to fix the Mauerlat to the gas block without an armored belt, then the first option is suitable - steel wire.

Mauerlat is a design designed accept and evenly distribute the load, created by the roof and perceived by the walls. With its help, the stability of the roof is ensured, provided that the Mauerlat is fastened according to all the rules. To do this, you need to know what a Mauerlat is, how it is attached to the aerated concrete wall, and also in what sequence the work should be performed.

Do you need a Mauerlat?

Without a Mauerlat it is possible to install roofing systems on frame houses, as well as buildings erected from timber and logs. They have this function structural element can make the top crown of logs or the top beam. For buildings made of aerated concrete, this is unacceptable, and therefore the installation of a Mauerlat must be done without fail.

With it you can:

significantly strengthen the building box;
increase the rigidity of the installed roof;
align the upper crown of the wall in a horizontal plane;
provide fastening roofing structure and the walls of the building.

The thickness of the Mauerlat depends on design features mounted roof. Most often, timber with dimensions of 150 x 150, 150 x 100 or 80 x 180 mm is used for its manufacture. It is also acceptable to use logs that have been cleared of bark and cut on one side. Trimming is done to ensure maximum adherence of the structure to the wall surface.

The moisture content of the wood used must be appropriate regulatory requirements. When using “raw” wood, it must be provided possibility of adjusting the anchor nut once every five years. After the timber has dried, the shrinkage of the wet wood will occur less intensely, and therefore the nut will need to be tightened less frequently.

The prepared wood undergoes special treatment antiseptic composition to protect the structure as much as possible from rotting and insect damage. Before laying, the log should be wrapped in waterproofing material, for example, bitumen-polymer. It is better to avoid using roofing felt.

If mounted metal carcass, for the manufacture of the Mauerlat, rolled products are used: channel or I-beam. It can be treated with anti-corrosion compounds.

Features of installing the Mauerlat

The Mauerlat must be laid in such a way that there is some distance left to the outer edge of the wall. As a rule, about 5 cm. Sometimes it is provided protrusion into which the mounted structure should rest. Subsequently, the roofing system will need to be attached to this structure.

To increase the service life of a structure made of wood, waterproofing must be provided. For this, roofing felt or any other waterproofing material is used.

Methods of fastening to aerated concrete walls

The preferred option is to install the element along the entire perimeter of the wall. To connect individual elements into a single whole, it is advisable to use straight lock, the dimensions of which directly depend on the geometric parameters of the timber used. For reliability, nails are additionally driven into the lock to form a rigid, integral system, to which the rafters are subsequently attached.

To secure the Mauerlat, you can use several methods:

chemical;
mechanical.

In the first case it is used special fastening capsules. The chemical substance, having penetrated into the material, ensures reliable fixation of the Mauerlat. At the same time, the condition of the top layer improves and the degree of heat and waterproofing increases. The capsules used for fastening are affordable.

To make a Mauerlat you must only use quality materials. The wood should not have knots. The waterproofing layer must not be damaged, which is achieved by using a special tool.

When mechanically fastening it is necessary to follow a certain procedure:

dowels are inserted into holes prepared in advance;
the fastening element is screwed in;
the teeth of the harpoon are firmly pressed into the aerated concrete;
surface expanded;
fastening has been done.

The Mauerlat must be fastened in such a way that adjacent links were not connected to each other. This improves the stability of the structure. However mechanical fastening involves creating an expansion force, which can cause some problems along the edge of the structure.

Fastening with anchor bolts and armored belt

For buildings built from aerated blocks, armored belt is required, since this one construction material not strong enough, which can cause certain difficulties when installing fasteners, especially anchor bolts. Therefore, the question of whether a Mauerlat is needed is not relevant in this situation: you simply cannot do without it.

Fasteners for the Mauerlat must be laid in advance. To construct a reinforced belt, it is advisable to use U-shaped blocks, with which you can form a characteristic groove around the entire perimeter outer wall. To avoid the formation of gaps, the corner blocks are sawn through.

The reinforcement frame is assembled using 12 mm reinforcement, which is tied with 6 mm jumpers. Threaded anchors are attached to the frame placed inside the gutter. They must take a certain spatial position, which is controlled using a stretched fishing line or cord. The anchors are placed at right angles to the mauerlat as close as possible to the top beam.

Fastening points should be located along the entire perimeter of the wall. Their number directly depends on the number of rafters: at least there should be the same or more. The fastenings must be positioned in such a way as to avoid contact with the rafters in the future. In order to reduce financial costs it is possible to fill not a solid armored belt around the entire perimeter of the wall, but only individual concrete pads.

After reinforcement cage together with anchor bolts will be placed in a pre-formed trench and concrete will be poured. To form monolithic design The filling process cannot be interrupted. Work must be carried out continuously along the outer wall. The gutter must be filled with concrete in one pass.

After the concrete has completely dried, the anchors will be securely fixed in the specified spatial position. At the same time very it is important to ensure their precise positioning during the solidification of the solution.

As soon as the concrete gains the necessary strength, the beams are laid on concrete belt and anchors, which should be inside pre-drilled holes in the wood. Then the nuts are tightened to secure the beams.

To determine the location of the holes in the timber, it is first laid on top of the bolts, and then force impact sufficient to cause dents in the wood. In these places holes are drilled for anchors.

For people uninitiated in the nuances capital construction It is hardly known on the roof why the Mauerlat is needed, what kind of structure it is. And the question of how to make a Mauerlat on aerated concrete causes complete misunderstanding. In fact, it attaches simply. The main thing is to prepare all the components: reinforcement frame, fasteners, timber beams and competently carry out waterproofing and wood processing.

Mauerlat - description in detail

This structure is made of wood beams. Performs the function of additional support for the load from the roof, with further uniform distribution along the entire perimeter of the walls.

If we summarize all of the above, we come to the conclusion that the Mauerlat is responsible for two important tasks:

uniform distribution of the weight of the rafters on the walls;
fixing the rafters to the frame of the building;

The Mauerlat can be made not only from wooden beams, but also from metal channels or beams.

In this option, the rafter system also needs to be made of steel. But this option is used extremely rarely due to the high cost of the material and difficulties in installation.

Materials and calculations

The strength and reliability of the roof depends on how securely the Mauerlat is attached to the aerated concrete. Therefore, everything needs to be calculated correctly. The minimum cross-sectional dimensions of wood beams must be no less than 10×10 cm. experienced craftsmen and designers recommend using higher values.

When using wooden logs for the mauerlat, one side should be hewn. This is necessary for a tight fit to the surface of the upper aerated concrete wall.

As for the type of wood, it is better to choose hardwood. Before installation, be sure to treat it with an antiseptic. Arrange the beams so that they evenly cover the entire upper part of the walls. Fasten adjacent parts with a straight lock and reinforce with nails.

The width of wooden beams is smaller than that of gas blocks, so they must be installed by moving them towards the inner edge, not reaching the end by 5 centimeters.

Ultimately, a solid structure with high levels of rigidity and reliable support for truss structure.

Preparing wooden beams before installation

As already mentioned, the beams should be treated with antiseptics before installing the Mauerlat on aerated concrete. They will prevent putrefactive processes in wood. Take logs with a section of 100 by 100 mm, but it is better to choose stronger ones 150 by 150 mm. Wrap them with waterproofing material, for example, bitumen-polymer. Ruberoid is not used for these purposes.

Only high-quality materials can create a durable structure; there should be no knots in the logs. Special attention the moisture content of the wood deserves - it must meet regulatory indicators. If wet material is used (meaning beams), then the anchor nut must be adjusted.

The nut should be tightened once a year for 5 years. This is necessary because in the first few years the wood is subject to intense shrinkage. And as the material dries, the nut must be tightened all the time. After 5 years, this procedure will have to be done less and less often. The Mauerlat is secured with special anchors with a nut and washer. They must have G- or T-shape with thread size M12 or M14.

According to European and international standards, the distance between two adjacent anchors should be no less and no more than 1-1.2 meters. This is especially true for earthquake-prone regions.

Attaching the Mauerlat to gas blocks without and with an armored belt

To complete this task, you need to ensure that the power plate is installed correctly and not securely fastened. There are two fastening technologies used by developers: with or without a reinforced belt.

Method of fastening a structure with an armored belt

When choosing aerated concrete for building walls, you need to understand that the frame of a house made from it will not cope with the weight of the roof placed on it. The construction of a reinforced belt will help her cope with this problem.

Dimensions of the armored belt and its purpose

An armored belt is a reinforced concrete closed structure that envelops the building perimetrically (that is, around the entire building). Tasks put forward to him:

protection against wall deformation;
additional rigidity for aerated concrete buildings;
adjusting the load on all wall surfaces evenly.

An armored belt is a kind of foundation intended for the roof of a building. Its dimensions are selected in accordance with the width of the walls and are approximately 25 cm. The outermost row should be laid out in blocks like English letter U. They will subsequently perform the task of formwork when pouring concrete.

It is extremely important that the Armopoyas is produced in a continuous monolithic structure.

Installation of armored belt

The step-by-step technology for producing armored belts is as follows:

First, formwork should be built around the perimeter of the house.
Next, an armored belt is made from monolithic blocks.
Then the frame is assembled from reinforcing bars.
Studs are installed for fastening.
Now everything needs to be filled with concrete mortar.
When it hardens, the formwork must be removed.

After completing the construction of the armored belt and removing the formwork, it will be possible to begin installing the Mauerlat.

How to properly install and secure the Mauerlat

This element and the rafter system must consist of the same materials.

Before installing the Mauerlat on aerated concrete, you must remember to treat it with antiseptic substances. Then wrap it in plastic waterproofing material type: hydroisol, steklomastelastoizol.

The Mauerlat is fixed to the wall structure with studs, iron wire or anchors. If it is made of wood, then it can be secured with special metal brackets.

After this, it will be necessary to fasten the Mauerlat to the rafters. The connection is made by tapping, tapping or sawing down to no more than 25% of the thickness. It is fixed with bolts, self-tapping screws, special angles, and steel plates.

The construction of a reinforced concrete armored belt will be able to prevent unwanted punching in aerated concrete blocks. It will contribute to the uniform distribution of gravity on the house box and the influence of dynamic and static forces pressing on the walls.

Installation technology without armored belt

The SNiP requirements state that installing a Mauerlat on aerated concrete house without a reinforced belt is in principle unacceptable. This is allowed to be done only in rare cases. This can be explained by the fact that an aerated concrete structure is not able to cope with the thrust snow load, dynamic and wind. The armored belt provides significant protection against deformation. As an exception, the Mauerlat is allowed to be mounted on a building without an armored belt.

This construction option will speed up and reduce the cost of the construction process. But in this case, you should adhere to the following requirements:

for the base, a light but larger beam is selected, having a cross-section of at least 20 cm;
it should be reinforced with steel elements: metal profile, nails or locks;
The climate where construction is taking place is not harsh and there are snow or wind loads, but they are of insignificant force.
The Mauerlat should be positioned in relation to the outer edge in the load-bearing walls at a distance of 0.5 - 1 cm. The Mauerlat is fixed with chemical anchors, steel wire or special pins.

It is very important before installing the Mauerlat on aerated concrete , accurately count the number of fasteners, as well as the distance between two adjacent fasteners.

You need to understand that the service life of the roof directly and largely depends on the strength and correct installation Mauerlat. And for this reason, errors, even seemingly insignificant ones, should not be allowed. This is the only way the roof will not cause deformation of the house, but will serve reliable protection from external and weather factors. This work should be entrusted to experienced developers and roofers.

The Mauerlat is attached to aerated concrete or foam concrete, as a rule, using a reinforcing belt located in the upper part of the wall structures. It is this that becomes the support for the Mauerlat and provides greater strength to the entire house.

Why do you need an armored belt?

As is known, aerated concrete is characterized by high sensitivity to local loads. That is, when exceeding permissible pressure drill used to create holes in the block, there is a high probability that it will become cracked or even split. To prevent such changes, an armored belt is installed; it also helps to avoid sliding and deformation of the blocks, which is caused by uneven pressure total weight.

What you need to know

The functions of the Mauerlat are to connect the building box and rafter system, as well as in dividing the load from the roof structure along all walls. Mostly wood is used to make fasteners. The best option is a timber made of hardwood, the surface of which is coated with an antiseptic composition.

It is desirable that the fastening of the Mauerlat to the aerated concrete wall be continuous along the entire perimeter of the wall structures. To secure individual elements, a straight lock of a suitable size is used. To ensure rigidity, nails are driven in, ultimately forming the beams unified system for the installation of rafters, connected to adjacent elements. The bars must be with inside masonry, while there should be at least 5-6 cm to the outside. To support the Mauerlat, a brick parapet is made along the outer edge of the wall, the 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 different conditions:

fixation with studs built into the masonry;
anchoring based on armored belt;
fastening the Mauerlat to aerated concrete with wire.

In the latter option, the wire is laid between the bricks so that the middle part is located under them, and external sides were outside. The length should be sufficient to freely thread through the beam and then tighten it. The number of strappings must correspond to the number of rafters. Using metal wire, the Mauerlat is then secured to the wall.

Reinforced belt

Fastening the Mauerlat to aerated concrete with an armored belt is the most preferable, since the blocks have an insufficiently dense structure and the difficulty of installing fasteners of any kind. It is worth noting the advantages of using a reinforced belt. First of all, this is leveling the upper part of the walls and strengthening the entire structure of the house; when arranging it, clamps for the Mauerlat are created in advance. The easiest way to implement it is to use U-shaped block elements in the form of a gutter along the perimeter of the external wall structures, and 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 a gutter and then poured concrete mixture. To ensure solidity, the mass is poured in one go. Before that on reinforced belt anchors with wire are secured. Special meaning has careful level matching. The studs are also fixed on the frame along a line in accordance with the tensioned cord, in a vertical position. Just as in the case of using steel wire, the number of rafter legs and anchor clamps must match. It is necessary to first determine the optimal location of the elements in order to avoid coincidence with the places where the rafters are fixed.

Fastening the Mauerlat to aerated concrete using studs

This option optimal for small buildings and roofs with lightweight construction, when there are no significant loads on the roof and walls. There are two types of studs: these are bolts that form a single structure with a steel square, or elements in the form of an L-shape. They are secured by laying the blocks several rows before the top, and the length should be enough for the lock nut and the thickness of the bars. The process is similar to the anchor method: the timber is put on studs when the masonry hardens and is fixed with nuts. There are also other methods of attaching the Mauerlat to aerated concrete, but they are used less frequently due to their lower reliability.

Sufficient rigidity and reliability of fastening is achieved by tying the bolts to the frame and additionally walling them with concrete. It is enough to put the power plate on the studs and tighten it to the blocks using nuts.

If it is necessary to attach the Mauerlat to aerated concrete without an armored belt, monolithic plugs and pillows in the walls are used. Their dimensions should be within 400 mm, they are recesses with a structure made of thin reinforcement or metal rods, and it is on this that the anchors are fixed.

Peculiarities

The use of anchors and studs requires preliminary creation of holes. A number of difficulties may arise here. For example, the fasteners may not be level enough, even if a cord and level are used; the most difficult thing to work with is liquid concrete. First of all, the exact location of the fasteners is set; points are marked on a board with a flat surface upper parts bolts, subsequently 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 with bolts; washers and nuts are additionally used.

Fastening the Mauerlat to aerated concrete should be carried out after choosing the fastening method and preliminary planning number and location of fasteners. First of all, reliable insulation is formed between concrete and wood. This is necessary due to the development of intensive wood decay, to prevent this process waterproofing material is used, laid in two layers. It can serve as modern options, and the usual ones, such as polyethylene or roofing felt.

When using wire, it is enough to make holes at a distance of no more than 35 cm for all fasteners, thread the wire, and twist the ends in such a way as to obtain the maximum connection between the wall and the Mauerlat.

It is worth noting that saw blades should not be used with an angle grinder as this tool is not suitable for wood. Failure to comply with this rule may result in injury during operation.

Sliding Mate

The installation of the rafters is carried out after the Mauerlat is tightly secured. Rafter structure can have hinged or rigid fixation, selection suitable option depends on the requirements that must be met by the mounting points of the Mauerlat to aerated concrete, the general configuration and type of structure (hanging or layered).

The hinged version can have different interfaces. The most common is a rigid mount, with no possibility of displacement or rotation. A sliding coupling is also used to ensure the beam moves and rotates in relation to the beam. The latter option reduces thermal expansion of wood and shrinkage of the building, all of which prevents the transfer of thrust loads to wall structures.

Three techniques are used to create a sliding mate:

the use of a special metal fastener to connect the rafters;
moving the beam beyond the walls and fixing it with a plate;
creating a groove in the rafter board and installing it on the mauerlat using a corner, staples or nails.

Hard mating

Concrete and wooden buildings, as well as structures made of timber. Due to the fact that both frame and timber houses are characterized by noticeable shrinkage, in the absence of the possibility of simultaneous displacement of the building frame and roof, there is a possibility of significant stress causing damage to the structure of the walls and rafters. To create a rigid connection, support bars with a length of within 1 meter are required, fixed to rafters, nails and steel angles. The rafter beam with the beam must rest against the Mauerlat structure in accordance with the pressure line. This helps prevent perpendicular displacements. Angles and nails eliminate lateral movement, and the latter must 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

Attaching the Mauerlat to aerated concrete has its own characteristics, which must be taken into account when arranging, in this way problems with the operation of the roof can be prevented. In the absence of experience and relevant knowledge to create a project and subsequent installation of a rafter system, it is advisable to contact professionals who guarantee reliable roof, which long years will protect the house from cold and precipitation. During construction, you should not save at this stage of work, as this may cause additional financial investments and time costs.

Rafter fastening scheme

Mauerlat is a part of the roof of any structure, which is a beam that is laid on top of the outer wall along the entire perimeter.

Its purpose is to distribute the load evenly from roofing system over the entire surface of load-bearing walls. It can be made of wood or metal. In the case of using a metal Mauerlat, take finished goods: I-beam, channel, corner.

To perform its function, the Mauerlat must be securely fastened. There are two ways: attaching the Mauerlat to aerated concrete without armored belt and with an armored belt.

Fastening the Mauerlat with an armored belt

Using aerated concrete as the main material for laying walls, you need to understand that it will not be able to withstand the load of the rafter system and roof, so the creation of an armored belt is mandatory.

Purpose and dimensions of the armored belt

Armopoyas is a closed structure made of reinforced concrete, running along the perimeter of the structure. Purpose of the armored belt:

preventing deformation of load-bearing walls;
giving additional rigidity to aerated concrete structures;
uniform distribution of load on the surface of the walls.

The armored belt is essentially the foundation for the roofing system. The dimensions of the armored belt depend on the width of the walls; for aerated concrete, the width of the armored belt is approximately 25 cm, while the outer row is laid out with U-shaped blocks, which will later act as formwork for pouring concrete mortar.

Important! The armored belt must be a continuous monolithic structure!

Prepared formwork before concreting

Armored belt device technology:

Construction of formwork around the perimeter of the building.
Creating an armored belt from concrete blocks.
Assembling a frame from reinforcement.
Installation of studs for fastening.
Pouring blocks with concrete mortar.
Removing the formwork after the concrete has hardened.

After the armored belt is ready and the formwork has been removed, you can proceed directly to attaching the Mauerlat.

How to attach a Mauerlat to aerated concrete

From him correct fastening to the load-bearing walls and rafter system of the building depends on its resistance to external influences, service life, noise and waterproofing characteristics and strength.

The Mauerlat must be made of the same material as the rafter system. If metal structures are used, then they are used as a Mauerlat. metal beams, channels, corners. For a wooden rafter system, the Mauerlat will be made of wooden beams. The cross-section of the beams depends on the design load, the type of roof and the diameter of the rafter beams.

Before installing a wooden mauerlat on aerated concrete blocks, it is necessary to treat the wooden beams with an antiseptic solution that protects the wood from insects and rot. It is also advisable to wrap the beams with a layer of waterproofing material. For this you can use hydroisol, elastoizol, hydrostekloizol, steklomast. These materials will not weigh down the structure and will create a layer of additional moisture insulation.

The Mauerlat is attached to aerated concrete walls using anchors, studs or metal wire. When laying beams, it is necessary to connect them at the joints with metal brackets.

Fastening diagram using studs (right) and staples (left)

Next, you need to attach the rafters to the Mauerlat. The connection occurs by cutting, tapping, sawing, but it should occupy no more than 25% of the timber. Fastening is done using self-tapping screws, bolts, angles, metal plates and polyurethane foam.

The main methods of fastening, starting with the most preferable:

Fastening with studs. This type of fastening can be used in the construction of both simple one-story buildings and auxiliary structures: baths, summer kitchens, garages, outbuildings, small country houses. This stud fastening method is preferred for most buildings.
Fastening with chemical anchors. The beams are attached to aerated concrete using a special chemical adhesive composition: “liquid dowel”, glued-in anchor, etc. The composition is made on the basis of polymers and contains adhesives in the form of synthetic resins. IN aerated concrete wall A hole is made as for a regular anchor, which is filled with adhesive, then a rod (reinforcement) is inserted into the prepared hole, onto which the Mauerlat is then installed. The strength of this design is quite high, however, with a large perimeter of the Mauerlat, this method will be expensive.
Fastening with steel wire. This method can be used if still at the stage of laying walls between aerated concrete blocks a metal wire was pushed through. Holes are made in the Mauerlat, where the wire is inserted and the strapping is made. It is very important that the number of wire ties is no less than the number of supported rafters.

Fastening the Mauerlat to a wall made of aerated concrete without an armored belt

In accordance with SNiP, fastening without preliminary installation of an armored belt is allowed only in exceptional cases. Aerated concrete is not a strong enough material and will not withstand spacer snow load, as well as dynamic wind load, so an armored belt is required!

In some cases, fastening the Mauerlat to walls made of aerated concrete blocks is possible without installing an armored belt. This significantly reduces the cost and speeds up construction. However, this is possible subject to the following conditions:

Lightweight is used as a base wooden beam with a cross section of no more than 20 cm;
the beam will be strengthened metal elements: locks, nails, metal profiles;
snow and wind loads in your region are insignificant;
The design of the rafter system eliminates thrust loads.

The Mauerlat is located at a distance of 0.5–1 cm from the outer edge load-bearing wall, and to secure it to aerated concrete, use studs, chemical anchors or steel wire.