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Types of lintels for houses made of aerated concrete blocks. Window openings in aerated concrete

At the stage of building a house made of aerated concrete blocks, additional reinforcement of door and window openings is required. This is necessary to strengthen the entire structure, prevent the formation of cracks or other defects on the walls of the building that may be discovered during further operation. For this purpose they are used different kinds construction crossbars, differing in cost, speed and ease of installation, and durability. Lintels over windows in a house made of aerated concrete solve many pressing problems, but before using them you should familiarize yourself with some of the nuances and important characteristics.

Types of lintels for walls made of aerated concrete blocks

Depending on the tasks assigned, they can be used in construction the following types jumpers.

Made from reinforced aerated concrete

They are used in the construction of buildings made of cellular concrete blocks. They are often used to cover load-bearing walls of residential and public buildings up to four floors. Equipping box openings with aerated concrete lintels in load-bearing walls is advisable for houses whose height does not exceed 17 meters. The advantages of using aerated concrete beams are as follows:

high speed of work;
small weight;
a clear and smooth surface that can be decorated with paint or thin-layer plaster;
absence of “cold zones”.

The disadvantage of these products is the high price, but it is compensated by other advantages.

Reinforced concrete

Made from steel rods and heavy concrete mortar. Such devices have wide range applications. They are used in construction for floors, and also as supporting structures. The main advantage is their availability and low price. The disadvantages of reinforced concrete lintels for aerated blocks include high thermal conductivity and significant mass.

Wooden

Such additional devices are used in the construction of houses made of brick, wood or cellular concrete material. The main requirements for buildings when installing wooden lintels is the presence of ceilings with wooden floor. The material used is first thoroughly dried and treated with an antiseptic. The advantage of wooden lintels over windows in a house made of aerated concrete is the ability to build them yourself. Also, one cannot fail to note their heat-retaining properties, low cost, and light weight. When influenced external factors, they, unfortunately, become deformed and rot. Exposure to external influences and short service life, in comparison with other types of crossbars, are their main disadvantages.

Metal profiles

They have excellent load-bearing characteristics, but their use is not always justified. The fact is that they are prone to metal corrosion. Yes, and the thermal conductivity of such products is very high, so there is a need for additional insulation. However, before making steel lintels over the windows in a house made of aerated concrete, you should take into account some nuances:

Before laying, it is advisable to cover the corners with paint on all sides;
for fixation, the profiles are fastened with a wire tie or welding;
the corners do not protrude from the wall, they are mounted in aerated concrete;
Before installation, the corners are wrapped with plaster mesh to ensure adhesion to the plaster.

Made from monolithic concrete

This method creating a concrete lintel on aerated concrete is the cheapest, but requires a lot of trouble. The result is a fairly strong structure that can withstand heavy loads. The disadvantages include the fact that after its installation, the uniformity of the wall surface is lost, which is revealed when a thin layer of plaster is applied. Before starting work on constructing a monolithic beam, it is necessary to construct removable formwork from plywood, boards or other similar material.

When choosing material for jumpers, take into account the following characteristics: the height of the building, its area, the weight of the walls, roof, ceilings (attic or between floors). It is also advisable to pay attention to the cost of the material and desired timing construction of the building.

For the reliability of the entire structure, it is very important to correctly calculate such parameters as the support area, the length and width of the reinforcing products. These components are determined based on the width of the window opening, as well as the height of the masonry above it. The depth of support of the lintels on an aerated concrete wall or minimum length We determine the establishments in the masonry depending on their type. The most popular options are:

The option without jumpers is also used in practice. To implement this plan, several requirements must be met:

The width of the window opening does not exceed 120 cm.
The height of the masonry above the frame is no more than 2/3 of the width of the opening.
Temporary formwork is being installed.
Reinforcement of several rows is carried out above the strengthening.
The voids are filled with aerated concrete adhesive.

Installation

Having become familiar with what lintels for aerated concrete are and the depth of support, let’s move on to the direct process of their installation.

Sequence of actions when installing aerated concrete U-blocks

Such beams are the most common in Lately, since the process of laying a finished factory product is quite simple. In addition, craftsmen manage to maintain the continuity of the masonry, while obtaining a perfectly flat surface. The technology is used to strengthen openings up to three meters, the work is as follows:

When can construction continue? Only after the structure has completely hardened do we continue construction. The timing depends on what time of year the construction takes place, on weather conditions, temperature and humidity. In hot, dry weather, concrete needs to be watered until it is completely set.

Stages of work when reinforcing an opening with a monolithic concrete product

Fill concrete mixture is, as already mentioned, the cheapest way to arrange a future window. Follow the step-by-step instructions:

Installation of jumpers from corners

Experts advise using metal corners to reinforce window designs up to 1.2 meters if the height of the subsequent masonry is at least two-thirds of the width of the opening. Subject to this requirement, we proceed as follows:

We cut out the grooves for the corners with an indentation from the edges of approximately 10-13 cm.
Processing metal structure anti-corrosion compound, wrap it with plaster mesh.
Make sure that the product rests on the walls.
We lay the corners on the inside and outside.

Along with this method, reinforcement is also successfully used to strengthen narrow openings. The use of aerated concrete or reinforced concrete beams in these cases is not justified. To reinforce one opening, four rods with a diameter of 10 mm are used. The rods are placed in the holes, which are then filled with glue or mortar. Blocks are then laid on the fixed rods.

Strengthening the opening is a process that requires certain knowledge and skills. To ensure the reliability and durability of the structure, it is important to correctly perform the calculations and consistently carry out the described actions.

Many inexperienced builders use reinforced concrete lintels when constructing wall openings. However, modern manufacturers offer more practical option. The use of jumpers for aerated concrete blocks allows such work to be carried out much faster, and also does not spoil appearance opening. In addition, the use of such material increases the thermal insulation of the box. All the subtleties of using aerated concrete are worth considering in more detail.

What is it used for?

The aerated concrete masonry above the opening is subject to serious pressure. High loads affect it not only during the construction of the house, but also during its operation. To evenly distribute the load on the opening, reinforcing bars should be installed using a wall chaser. After placing the reinforcement in the groove, it is sealed with mortar.

How to choose the type of lintel for a door or window opening? To accept correct solution, indicators such as the availability of material and the length of the span to be covered should be taken into account.

Features of installation of different designs

Openings that are quite long can be covered with monolithic reinforced concrete products. If the length of the opening does not exceed 3 m, reinforced concrete beams placed in permanent formwork should be used. If the opening in the aerated concrete wall is only 1.2 m long, there is no need to make a lintel. This condition is met in cases where the masonry above the opening has a height of no more than 2/3 of the width of the opening itself.

Piers in load-bearing structure must have a width of at least 60 cm. If it is necessary to make a partition of smaller width, it should be built of brick. For such partitions, aerated concrete blocks with reinforcement can also be used.

More optimal solution To maintain the thermal insulation of the external walls of the house, it is necessary to create lintels that are made of aerated concrete. They are installed above window and door openings. Such blocks usually have a density grade of D700. For this purpose, monolithic products in permanent formwork, which is represented by U-blocks, can also be used. The latter have a density of D500.

Sometimes reinforcing lintels is the simplest procedure, thanks to which you can cover an opening no larger than 174 cm. When choosing lintels, you should take into account their weight. Monolithic reinforced concrete products are very heavily loaded load-bearing walls. To install such structures, you will need to use lifting equipment. To lay reinforced aerated concrete structures for masonry, there is no need to create special unloading areas.

The lintels made over the openings are usually 2 cm long. The wall of the U-block, which is thicker, faces the street. The assembly of permanent formwork from such blocks is carried out on a temporary support. After the solution has completely hardened, it is removed.

Monolithic products

When using monolithic reinforced concrete lintels, it is possible to block openings up to 3 m wide. Such structures are second only to ceilings made of heavy concrete. U-shaped reinforced concrete products are installed without the use of special equipment. This circumstance is a significant advantage.

However, this technology requires good preparation and a fairly large amount of work during which the jumper will be created. The product is equipped metal frame in U-shaped blocks. If they are 20 cm wide and the tray is 12 cm wide, it is permissible to reinforce them with 2 reinforcing bars. All blocks that have a tray width greater than 15 cm must be reinforced using 4 rods.

Openings can be constructed without lintels if several mandatory requirements are met. One of them has already been mentioned above - the masonry above the opening should be no more than 2/3 of the width of the opening. To create rows of masonry with such an opening, it is necessary to use temporary formwork. During work, aerated concrete adhesive is used.

If the height of the masonry is insufficient, the opening should be reinforced with an ordinary non-load-bearing retaining structure. Steel angles can also be used. When using them, several subtleties must be taken into account:

Steel corners can be painted with rust. They are coated with paint both inside and outside.
The support on the masonry has a minimum length of 20 cm.
It is better if the corners are fastened with steel tape. A wire tie is used for this. Welding can be used to fasten the tape.
The corners are usually recessed into aerated concrete. They should not protrude from the wall.
Steel corners must be wrapped with plaster mesh if the walls are subsequently plastered.

When creating a monolithic jumper, you will need to perform the following steps:

It is necessary to combine reinforced structures using lifting equipment. The jumper is installed with the arrow pointing up. It is better to make the support with a depth of 25 cm. It is optimal if it is 30 cm. The width should be equal to the width of the block.
The jumpers must be fastened together. The element should not be deformed. It should not be shortened or made into the hole element. Violation of the integrity of the structure will lead to loss of its strength.
The next jumper is laid close to the previous one.
The surface of the structures is leveled with a plane.
The mixture for thin joint masonry is expected to set.

When performing such actions, you can design a door or window opening with your own hands. The support of the lintels on the walls should be as reliable as possible. This can be ensured by performing correct calculations.

The main task window systems is protection from weather conditions, maintaining heat in the house. From correct installation Windows depend on safety and durability.

Since aerated concrete is very easy to saw, using a special corner you can easily get a perfectly straight window opening.

Aerated concrete masonry above the window experiences heavy loads not only during the construction of the building, but also during further operation.

Reinforcement units for a building made of aerated concrete blocks: 1 – wall made of aerated concrete blocks; 2 – reinforcement at the joints between floor slabs; 3 – reinforced concrete belt; 4 – insulation elements of the armored belt; 5 – reinforcement of lintel support zones; 6 – reinforcement of the window sill zone; 7 – reinforcement of blank walls large area; 8 – reinforcement of the support seam.

In the standard case, in order to evenly distribute the load on the side parts of the entire window opening (and partitions), the reinforcement is installed using a wall chaser so that the 12-mm reinforcement easily fits into the groove. The latter is filled with mortar, and reinforcement is placed inside the groove so that its ends extend more than half a meter.

Wooden boxes For windows in a house made of aerated concrete, they are produced without grooves. After sawing and planing the bars of the required size, quarters and grooves are selected. Spikes and eyes are cut out at both ends of each bar. Next, we assemble the “mosaic” into a box. Often the bottom block is left intact.

The technology for constructing windows and partitions depends on the load-bearing or non-load-bearing lintels used, and the nodes supporting the walls. If window frames are used, they are inserted into the opening and secured with nails or anchor bolts.

The seams between the wall and the frame are insulated polyurethane foam or mineral stove.

Installing lintels over window openings is a difficult stage in the work, requiring care, diligence and adherence to technology. The support of any lintel on an aerated concrete wall must be installed to a length of more than 2 m. Next, the opening is made like this. Taking into account the thickness of the walls, one or two lintels are placed close to each other. If the window is 1.2 m wide or more, it must be strengthened by extending the support to 2.5 m.

Jumper diagram.

The following lintels are used in the construction of aerated concrete buildings:

Depending on the reinforcement zone:

the bearings are reinforced in the tensile zone with working reinforcement, calculated for bending strength, support shear, deflection, and lateral force;
non-load-bearing ones are structurally reinforced (gas and reinforced concrete lintels).

Depending on the material used:

aerated concrete, divided into lintels made of U-shaped aerated concrete blocks and reinforced lintels made of aerated concrete;
reinforced concrete;
wooden;
rolled metal profiles - angles, I-beams, channels.

Installing jumpers

Option for installing formwork for pouring a lintel.

Window opening and partitions in aerated concrete walls They are partitioned with prefabricated lintels made of timber or monolith. Prefabricated monolithic lintels are produced from U-shaped heavy concrete (M200) blocks with the assistance of permanent formwork. U-blocks are aerated concrete blocks made in a specific format, the inside of which is reinforced. The walls of the U-block perform the function of formwork (load-bearing capacity) for monolithic lintels and thermal insulation. The frame is made from steel reinforcement class A III. Prefabricated lintels, depending on the size and weight, can be produced by lifting mechanisms or independently by hand. Next, the lintels are laid only on the mortar used for laying the walls. The window opening in aerated concrete does not have a quarter. Wooden boxes are fastened with galvanized nails or metal brushes. The gaps between the window opening and the frame are sealed with insulation with elastic gaskets or polyurethane foam, and the slopes are treated with plaster.

The window sills of the external walls are protected by a steel roof drain.

Options for insulating a lintel over an opening in a wall made of aerated concrete block.

The window opening is covered with U-shaped blocks (prefabricated monolithic lintels) in several stages.

Installation of U-blocks with a wide part on the outer side of the walls on a prepared base to a depth of at least 2.5 m. In the case of block lintels above the opening, temporary supports are installed before they are laid. To avoid sagging of the lintel, the window support must be reliable.
The window opening also requires sizing. Sizing vertical seams between U-blocks is made with thin joint mortar.
Checking the evenness of block laying building level and, if necessary, leveling the masonry with a rubber hammer.
To properly design the opening, you need to perform reinforcement. The reinforcement (frame) is placed in the resulting cavity between the recesses of the U-blocks in such a way that it is covered with concrete on all sides.
Laying thermal insulation (for example, polystyrene) between the reinforcement and the outer wall of the U-shaped block.
The opening is wetted in the area of the U-bridge with water.
Filling the cavities of the blocks with compacted fine-grained concrete. The composition of concrete and reinforcement are selected taking into account the perceived load.
Leveling the concrete surface.
Removing temporary supports after the concrete mortar has completely set in U-shaped aerated concrete blocks.

Installation of reinforced lintels

Location of anchors in the window and doorways when facing aerated concrete walls with brick: 1. Facing wall made of brick. 2. Anchor.

To simplify the work, you can purchase ready-made jumpers, rectangular in cross-section, from reinforced aerated concrete autoclaved hardening, which cover spans of windows and partitions of no more than 2.5 m. Reinforced lintels are characterized by strength, thanks to a three-dimensional frame made of steel coated with an anti-corrosion compound. They also provide uniform load distribution and simplify the selection of jumpers. The main problem when building houses from aerated concrete is the appearance of cold bridges from windows. The thermal conductivity of a lintel made of reinforced concrete is low, as a result of which the likelihood of cold bridges disappears. As a result of installing such jumpers, a homogeneous base for finishing with plaster is obtained. There is a variety of lintel sizes to suit any block width. Thus, reinforced lintels have a number of advantages. Firstly, low thermal conductivity. Secondly, light weight. Thirdly, high fire resistance. Finally, the exact geometric dimensions. This option significantly saves time on building construction and is the most environmentally friendly.

The reinforced lintel is used as a single-span beam that takes the load along its entire length.

Layout of the mounting points for the window block box in the wall opening: 1 - places for permanent fastening of the structure to the wall.

To obtain a jumper required width windows we perform several actions:

We make a combination of reinforced lintels using lifting vehicles, for example, a crane, or with our own hands. The jumper must be installed with the arrow pointing upward. The depth of the support should be at least 25 cm, optimally 30 cm of masonry, the width should be equal to the width of the block, the height should be equal to the height of one or two blocks. You can also attach two jumpers at once. Installation of window supports is carried out only with monolithic blocks.
We fasten the jumpers together and in the places of support with glue or mortar for fine joint work. Under no circumstances should the jumper be deformed to shorten it, holes should be drilled, or the integrity of the cross-section of the block should be violated in any way. Otherwise, this will lead to loss of thermal protection, deformation, and deflection.
Place the next jumper tightly against the previous one using a rubber hammer.
Level the surface of the jumpers with a plane.
We are waiting for the mixture to set for thin-stitch masonry.

Installing a jumper from a metal corner

Pouring a monolithic concrete lintel.

Aerated concrete can be easily cut using a special saw. A special corner promotes optimal smooth cut, as a result, select the right size block to the window is not difficult. It is important to note that the cut block is inserted more than a meter long. Using pre-purchased blocks of various sizes, you can easily adjust the height of the windows either by trimming the block, or by selecting blocks of different sizes.

Concrete lintels, having the property of high thermal conductivity, unlike aerated concrete, require additional insulation, for example, using polystyrene. The process is labor-intensive (aerated concrete, polystyrene, concrete) and requires professional intervention. It is better to install this kind of jumpers on wide windows. In addition, the insulation will contribute to weakening of the frame and loss of vapor permeability. The latter contributes to the formation of condensation and mold inside the window.

One of the most reliable and simplest ways to install an aerated concrete block on lintels is to lay lintels from a metal corner into the body of the aerated concrete block at a distance of 1/3 of the width from the edge. If the width of the windows is up to 1.2 m, then the 50th corner is suitable, if up to 2 m - the 75th corner. The metal corner is durable and, therefore, able to hold a number of glued gas silicate blocks. To ensure maximum strength of the wall, aerated concrete is laid using glue and dressing. The advantage of a metal corner is that the masonry from the outside looks uniform. The dimensions of reinforced concrete lintels depend on the load of windows and partitions, and the pressure from unset masonry. The following jumper profiles are distinguished:

channels, I-beams;
profile pipes;
hot rolled steel angles;
unequal and equal flange steel angles.

For structural reasons, for more convenient laying of aerated concrete, it is optimal to use four corners instead of two. Rolled metal profiles must rest on the wall more than 25 cm and 40-50 cm in earthquake-prone regions.

The use of monolithic reinforced concrete lintels is a labor-intensive process. The technology for installing such a jumper includes:

height selection;
reinforcement;
installation of formwork;
formwork support;
tying reinforcement;
concreting reinforcement.

Wooden lintels are the most economical option, having a small thermal conductivity coefficient. Main disadvantage– the unreliability that the openings will have, therefore the use of wooden lintels is impractical.

Window block installation

Installation of window block.

In order to prevent the formation of cracks, condensation, mold, mildew, and reduce sound insulation, it is necessary to perform all technological methods:

Leveling the surface of masonry slopes.
Impregnation of the opening with primer.
Removing dirt and debris.
Applying primer to the openings where the tapes are glued.
Thermal insulation of internal slopes.
Prepare sealing and insulating tapes equal to the width of the window plus 2 cm.
Gluing a 60 mm wide vapor barrier tape to the vertical and horizontal upper sides of the slope, retreating 30 mm from each side of the opening using a limiter strip. Do not pull out the tape. The tape must be applied in an even layer without bubbles or folds.
Carefully fill the tape at the joints (joining is allowed from top to bottom, no more than one per opening).
Gluing the vapor-permeable sealing tape first to the vertical sides, then to the horizontal ceiling, which can be laid both to the frame and to the surface of the window opening. At the same time, remove the protective paper tape. The cross-section of the vapor-permeable tape should be more than 70% of the length of the tape compressed by the window.
Installation and fastening of the window so as not to tear the tapes glued to the window opening.
Insertion of load-bearing blocks that do not interfere with the fastening of tapes.
Filling of pre-moistened seams with polyurethane foam for heat, sound insulation and durability, evenly from bottom to top, 40 mm thick.
Gluing the free edge of the vapor barrier tape to the surface of the block.
Fastening trims, drain and window sill.
Sealing the cracks that the opening has.

List of tools and materials

Installing a window in the opening.

Required tools:

mallet;
wall chaser;
carriage;
ladle;
grater;
hacksaw for aerated concrete;
building level;
rubber hammer;
plane;
roulette;
Master OK;
putty knife;
ruler level, rule;
drill with special attachment;
concrete mixer;
gloves;
bucket.

Required materials:

expanded polystyrene;
steel reinforcement;
U-blocks/aerated concrete reinforced lintels;
galvanized nails/metal brushes;
mortar for thin joint work;
concrete solution;
plaster;
polyurethane foam.

Materials for concrete mortar:

cement;
water;
sand;
or a ready-made solution.

Correct reinforcement of objects from aerated concrete material is considered the key to long-term operation of the structure and makes it possible to prevent the formation of cracks and deformations. Lintels for aerated concrete blocks are used to increase the level of strength gas silicate walls cottages and low-rise buildings. These elements are installed during the construction of openings. This measure allows you to redistribute loads from floors and upper floors, excluding the formation of cracks in the opening area.

Elements made of iron and concrete are considered cold and require additional insulation.

Lintels made from aerated concrete raw materials have the same thermal conductivity as block material.

To cover technological openings in aerated concrete walls, the following types of lintels are installed:

factory-made;
U-shaped elements of prefabricated type;
structures using metal corners;
monolithic type products.

The flooring option is completely dependent on the length of the entire structure. To strengthen three or more meters, monolithic elements are made. The opening area from 3 to 1.2 m can be covered with U-shaped blocks.

It is allowed not to install lintels on openings whose width is less than 1.2 m, if at least 2/3 of the opening length is to the upper edge of the wall.

Prefabricated lintel made of aerated concrete

The height of the material that has been hardened in an autoclave is 20 and 25 cm. The size of the support must be at least 25 cm. To ensure that the height of the masonry is not violated, additional products are made.

For the window lintel select required amount aerated concrete bars, the thickness of which does not exceed the size of the opening. If the wall thickness is 400 mm, you can install a pair of 150 mm bars and one 100 mm.

The standard dimensions of lintels for walls made of aerated concrete blocks are as follows:

All material manufactured in industrial conditions, fully meets the requirements of GOST, is lightweight and easy to install using an adhesive composition.

After installing the lintel, the surface remains flat, which makes finishing easier. The only disadvantage of the products is the high cost.

Lintel in a permanent formwork structure: installation rules

The use of U-shaped material makes it much easier to cover the opening areas. The dimensions of blocks of this shape coincide with the parameters of ordinary wall stones. Installation can be done manually without using special equipment.

When installing a prefabricated window lintel in a house made of aerated concrete, a regular adhesive solution is used. A thickened external wall creates protection against thermal energy loss. As an addition, insulation material in the form of mineralized wool or polystyrene foam is laid on such a wall.

The U-block is considered a prefabricated element, the typical parameters of which make it possible to select required size by lenght. There is a special tray inside for storing reinforcement cage and pouring concrete mortar.

Installation is performed as follows:

For the assembly of shaped blocks, a rigid base is prepared along the cut of the outer opening section. To prevent deflections from forming during the pouring process, the base is supported at certain points metal pipes or wooden blocks.
The blocks are laid on the platform, and a 25 cm long overlap is placed along the walls. In this case, the supporting wall elements should not have cracks or other deformations.
The thickened wall is placed on the outside, and insulating material is placed along this edge. The tray ends are glued together with a mortar compound prepared in accordance with the manufacturer's instructions.
A frame made of reinforcement is placed in the tray, the rods of which are fastened with knitting wire in increments of forty to fifty centimeters.
U shape block is poured concrete composition brand M200, characterized by a soft consistency.
At the time of pouring, it is necessary to ensure uniform filling of the cavity and enveloping the metal rods. For this purpose, the solution is applied in layers and leveled with a trowel.
Dismantling of the platform is allowed after three weeks.

A U-shaped aerated concrete lintel over a window can be assembled in another way. A platform is leveled on the surface of the ground or indoors, a stable base is arranged, for which it is recommended to use wooden flooring.

The tray bridge is made to the required length, the blocks are connected with glue. The fittings are installed and the mortar is poured using familiar technology.

After twenty-one days, the lintel is lifted onto the wall. To assemble the structure, this method is considered more convenient, but lifting will require the use of lifting equipment.

Element on a metal corner

The installation of lintels in aerated concrete walls can be done in this way. The opening is covered with blocks laid on equal-flange profiles No. 75. If the structure exceeds two meters in length, angle No. 100 can be used. Their strength will give the beam sufficient load-bearing capacity.

Metal corner lintels in aerated concrete walls can be installed in two ways:

the corner shelves are cut in the center or a third from the edge;
metal is placed along the edges with the outer and inside.

The metal recessed into the blocks does not disturb the appearance of the masonry row. The wall can even be painted later without applying a layer of plaster to the top.

If the facade is planned to be plastered, the corners can be installed along the edges of the beams. If the aerated concrete is trimmed correctly, the lintel will be smooth.

Before installing a corner lintel for aerated concrete, certain features should be taken into account:

the metal surface is cleaned from corrosion, primed, and painted;
the corners are connected to each other by welding;
After making cuts, it is recommended to remove dust from the surface;
on each side there must be an overlap of 25 centimeters or more;
To make the finishing process convenient, the corner should be wrapped with a mesh for plaster;
Before laying the products, an adhesive composition must be applied to the ends and cuts.

Elements on reinforcement bars

Jumpers for windows in a house made of aerated concrete are prepared using reinforcing rods. For sections not exceeding one and a half meters in length, rods with a diameter of 1.2 - 1.6 cm are used.

Before installation, grooves are cut in the lower part of the block. If the assembly is performed at the bottom, the products should be turned with the grooves up. The end sections of the blocks are glued together, the furrows are cleaned of dirt, and filled adhesive solution.

Metal rods are laid, empty spaces are filled with mortar, and the surface is leveled with a spatula. After seven days, such a lintel can be placed over the opening reinforcing bars down.

When forming a lintel immediately, the rods are laid on the walls. Their ends are bent at ninety degrees and wound in 9 cm on both sides. Laying is done using mortar.

The prepared grooves and end parts are coated with glue and reinforcement is laid. The lower surface is rubbed with a solution.

How else can you make a lintel over a window made of aerated concrete? Let's consider the option of a monolithic element, the basis of which is M200 concrete mortar. The material is cold and requires additional insulation. Yes, and when constructing a formwork structure, certain difficulties arise.

The advantage is that such an element can cover large openings. It should be noted that the shape does not matter. For example, you can arrange an arch or a regular window.

For small openings made of aerated concrete, it is possible to prepare a lintel with your own hands. The height of the element will depend on its size, but it should not exceed a twentieth of its length.

For example, you need to arrange a ceiling over a span of 2.8 m. It follows that the height is at least 14 cm. You will need from four to six pieces of reinforcement, the diameter of which is 12 mm. The rods are connected with knitting wire in half-meter increments. The length of the supports is thirty-five centimeters on each side. The supporting edges are reinforced with a mortar layer, the thickness of which is 1.5 cm.

Monolithic lintel can be manufactured in removable and permanent formwork structures. In the first case, boards are used either plywood sheets. Insulation material is laid out from the inner edge of the boards.

The second option is the size of the formwork width is less than wall block, and the difference in size is the thickness of a pair of insulating layers. In this case, the thermal insulation material is glued after the formwork panels are dismantled.

A convenient option for a permanent formwork structure is extruded polystyrene foam sheets. The material has good thermal insulation properties and strength indicators.

A frame made of steel reinforcement is laid inside the structure and raised by a few centimeters with pads so that the concrete mass can create a single protective layer.

Pouring is carried out concrete mortar M200, which is laid in layers so that there are no void areas left. After three weeks, such a jumper gains full strength.

After most of the masonry of aerated concrete walls has been completed, the next stage of construction begins, when it is necessary to make ceilings for door and window openings. The moment comes manufacturing and installation jumpers.

The simplest option is to use ready-made codes jumpers from reinforced aerated concrete. Ready-made lintels are independent load-bearing elements and are designed to cover openings up to 175 cm wide. They are reinforced with a steel frame and do not require additional insulation.

The installation of aerated concrete lintels is carried out on a thin layer of adhesive mortar, symmetrically relative to the opening being blocked. The minimum support area on the wall is 250 mm or 300 mm and depends on the width of the opening.

The advantage of installing ready-made jumpers is, of course, the speed and resulting smooth, uniform and flat surface walls, which makes it easier plastering work. The disadvantage of ready-made aerated concrete lintels is their unreasonably high price.

Jumpers made of U-blocks

The second option is to make jumpers directly on construction site using so-called U-shaped blocks (tray blocks).

U-blocks are laid on the prepared mounting base. It can be done using a board and timber. The base for the lintel must be strong enough and should not bend when poured with concrete assembled structure. To do this, the base of the board should be supported, for example, with racks, especially in cases with wide openings.

On the platform made in this way, the U-blocks are placed end-to-end, and the vertical seams between them are filled with a thin layer of adhesive solution.

Insulation should be placed inside the U-blocks, closer to the outside (a sheet of foam plastic or mineral wool), since the wall thickness of U-blocks is 60 mm and is not enough to insulate a concrete monolith.

Next, a reinforcement frame is installed inside the lintel. The frame consists of four reinforcement bars, fastened together in cross section, with a cell pitch of 100 mm 150 mm. It is recommended to use rod reinforcement with a diameter of 12 mm for jumpers, wire with a diameter of 6 mm for ring tying, and knitting wire to fasten the frame.

Concrete is poured into the lintel cavity, which must be compacted and leveled. The recommended grade of concrete is no less than M200, i.e. standard foundation concrete.

The use of U-blocks greatly simplifies the process of making lintels, and the resulting floors have good load-bearing capacity. Perhaps the only drawback of tray blocks, as in the case of ready-made lintels, is their price. On average, the cost of one U-block is $10.

Jumpers using metal corners

Third manufacturing method jumpers for openings in walls made of aerated concrete, consists of laying blocks on lintels made of metal corners.

An important condition is that the corner should be cut into the body of the block, retreating at a distance of 1/3 of the width from the edge of the block. It is not allowed to install a corner on the inside or outside of the blocks. The thickness of the corner depends on the width of the opening span. For an opening width of up to 1.2 m, use the 50th corner, for an opening width of up to 2 m, use the 75th corner.

The bearing capacity of the corner is sufficient to support one row of aerated concrete blocks laid on glue. Aerated concrete blocks are placed end to end, and the ends of the vertical joints are filled with a thin layer of adhesive mortar.

After the glue hardens, the resulting lintel is a structure made of monolithic aerated concrete, which has a strength no lower than that of an aerated concrete block. After installing the windows, the part of the metal corner located on the outside must be insulated (with foam plastic or mineral wool) and plastered.

The disadvantage of this method is that if the corners are inserted incorrectly and improper insulation their outer part, perhaps the appearance of condensation on the slopes indoors.

Monolithic concrete lintels

The fourth method, used in construction, cannot be called completely simple, but it is reliable and quite inexpensive compared to using ready-made aerated concrete lintels and U – blocks. It consists of manufacturing by concreting with reinforcement and simultaneous insulation of lintels in wooden formwork made above the opening. This method is reminiscent of the second option, only there the U-blocks served as permanent formwork.

To do this, after the laying of the blocks has been completed, to the border of the support zone of the future lintel (250 mm or 300 mm from the window opening), it is necessary to erect wooden formwork using boards, timber and OSB (or laminated plywood). 100 mm insulation is inserted inside from the outside. On the inside, the insulation is coated with an adhesive solution for better adhesion to the concrete. A frame of reinforcement is installed inside the formwork, everything is the same as in the case of U-blocks.

The next step is to fill the formwork with concrete to a level equal to the height of the block, that is, 200 mm.

After the concrete has hardened, the formwork is removed and as a result we get a reinforced concrete lintel insulated from the outside.

The insulated outer part of the lintel must be reinforced and plastered using alkali-resistant facade mesh.

The last manufacturing method given jumpers for openings in walls made of aerated concrete, is the most appropriate from an economic and constructive point of view. This option will be much cheaper than the first two, but more expensive than the method using corners. But we will get a full-fledged reinforced lintel, which will never give rise to cracks.
In the following articles, read about how to make

Window installation
Stages of construction from aerated concrete