Strengthening the opening in aerated concrete under a metal door. The nuances of installing entrance doors in aerated concrete houses

Installation of doors in a house with walls made of aerated concrete blocks (from cellular concrete blocks).

The user manuals of the American companies producing aerated concrete Contec, E-crete, Delta indicate that, if necessary, doors in relatively small openings (up to 91 cm) can be installed directly on aerated concrete. The door frame is fixed in these cases with cellular concrete anchors. (see fig. 1, variant D)

Why are more complex attachment points for door frames to aerated concrete walls invented? Aerated concrete is a rather fragile material. When installing heavy steel doors, doors in large openings (openings of more than 91 cm, garage doors, etc.), doors in commercial premises with high traffic of visitors, aerated concrete in places where the door frame is directly attached can experience significant shock loads (shearing, pulling out) . To prevent the gradual coloring of the porous structure of aerated concrete (cellular concrete) under a very small anchor area, it is recommended to install door frames in such a way as to distribute the loads from opening and closing doors over a much larger area. When installing doors in individual houses made of aerated concrete, it is possible to use intermediate securely fixed wooden frames or embedded bars. Wooden frames can be made of dry board, glued wood (furniture board), timber or plywood. The wood must be pre-impregnated with indelible antiseptics or, even better, impregnated with antiseptics under pressure. You can use heat-treated wood, as it is much less prone to decay. When using ordinary dry wood, preference should be given to larch - as one of the most rot-resistant woods available for a reasonable price.

In simpler cases of installing interior doors, they use either a embedded beam embedded in aerated concrete (picture No. 1, option A), or overhead wooden panels along the thickness of the wall in the opening (picture No. 1, option B). The wood is installed on a layer of aerated concrete adhesive or tile adhesive to prevent the formation of voids between the wall and the wood panel. The tree is fixed on the wall using anchors for cellular concrete and, if necessary, to prevent hinged rocking - using self-tapping screws with a length of at least 7.5 cm from 30 to 150 kgf The value of pull-out loads is 50% of the above values). Door frames are attached to the wooden frame of the doorways with self-tapping screws.

Wooden panels can be solid, covering the entire height and width of the doorway (Fig. No. 2, option A), or made from pieces of wood installed at intervals of not more than 61 cm in the centers (Fig. No. 2, option B). In the second installation option, after installation and fastening to the wooden planks of the door frame, the free gaps between the wall and the door frame are foamed with mounting foam with a small degree of expansion. This allows the door frame to be more rigidly fixed due to the oppositely directed holding forces of the self-tapping screws and the expanding forces of the mounting foam.

For doors in large openings (more than 91 cm or garage doors), it is recommended to secure the wooden frame-frame of the opening more firmly with adhesive anchors (Fig. No. 1, option B). In this case, threaded studs or anchors are embedded in a drill hole with a depth of at least 15 cm, aerated concrete blocks of doorways with a step of no more than 61 cm using epoxy resin. The use of adhesive for aerated concrete is not recommended, since due to its fluidity it is impossible to achieve uniform filling of a horizontal drilling hole. You can use aerated concrete adhesive or mortar when fixing an anchor or stud while laying an aerated concrete wall. At the same time, a groove is cut out in the aerated concrete block, open from above, an anchor or stud is laid, and the cavity is filled with glue or mortar. To the embedded stud on a layer of adhesive for aerated concrete or tile adhesive, with the help of a washer and nut, a wooden strapping of the opening is attached. If necessary, the strapping of the opening is additionally fixed with self-tapping screws. Either garage hinges or a door frame are attached to the harness.

Figure #1. Nodes for fastening door frames to walls made of aerated concrete (cellular concrete)

Aerated concrete is a porous material, has high thermal insulation properties, low weight, and dimensions can significantly reduce the construction time of objects. However, it has poor strength characteristics, so the structure of the blocks does not allow the use of traditional methods for installing a door into a house wall.

The main parameter questioned by developers who encounter aerated concrete for the first time is its strength. That is why, to strengthen the opening, lay out with a brick or concrete. The optimal solution, of course, is the installation of a canvas whose size does not exceed 700 mm. Fastening with the help of special elements will make the structure reliable and durable.

The width of a standard entrance door with a height of 2-2.3 m varies from 900 mm and more. Therefore, without special strengthening measures, the box can gradually become loose.

Several methods have been developed to strengthen the entrance and interior openings:

The width of the box should be 2-6 cm less than the size of the opening in order to be able to fix it.

Way		Process	Nuances
Embedded parts		Installed on both sides of the door. Their number and parameters are specified in the project documentation. At the top, the mustache of the part is fixed into the seams between the elements of the jumper, and on the sides - between the gas blocks. The box is subsequently attached to the mortgages with special fasteners.	All welded parts, the contact of which with the masonry mortar cannot be avoided, are covered with an anti-corrosion coating.
Overhead wooden structure		Installation is carried out in the absence of another type. Along the perimeter of the opening, a U-shaped strapping is fixed with anchors.	So that the strapping does not stand out on the plane of the walls, a drink is made under it in aerated concrete. Since the wooden strapping will reduce the size of the opening, it is necessary to expand it before performing work.
Welded corner frame		Can be used to install a large double door. In terms of reliability, the method is not inferior to the design with embedded elements. The web of corners is cut into pieces equal to the length of the sides of the opening. Separate parts are connected by welding into 2 frames, which are bordered by the edges of the wall. Between themselves, the U-shaped elements after 50-60 cm are connected with metal plates 3-4 mm thick, the length of which depends on the thickness of the span.	At least 3 plates are placed on the side of the frame. Anti-corrosion treatment is required.
Ankera	Chemical	After hardening, the threaded part of the anchor is securely fixed in the aerated concrete wall. These elements require pre-drilling holes, followed by filling them with a reagent.	It is possible to further improve the strength characteristics of aerated concrete by priming it with a strengthening, waterproofing compound.
	Spacers	The working end, entering the aerated concrete block, splits, becomes thrust, and the bolt is fixed.

Aerated concrete is a fragile material, so the use of impact tools is not recommended. To install a door in the wall opening from blocks, the box is fastened with anchors and self-tapping screws.

The main stages of installation

The choice of method depends on such factors as the size and weight of the web, location and what functions will be performed.

1. Installation of small interior doors allows the use of embedded bars and anchoring.
2. When installing interior and exterior doors made of wood, you can use embedded bars.
3. If a massive metal door is placed, then the gas block must be strengthened with a welded frame.

Way	Installation steps
Welded frame	The masonry is reinforced with a primer or mesh. The welded frames made of steel corners are primed, painted, put on the side edges of the opening. Both parts are interconnected with metal plates at the locations of the box. The resulting structure is fixed to the wall with anchors and self-tapping screws. The slopes are plastered and the door is installed, fixed to the frame elements. This method is the most reliable and affordable.
Wood binding	To reduce shock-deformation loads in the places where the iron door is attached to the gas block, the placement of a strapping frame or embedded beams is required. Prime the wall in the opening area. Take 2 sets of oak or larch timber according to the height and width of the future strapping, make U-shaped structures. Insert the strapping parts into the opening, fix with anchors. Empty gaps are filled with foam. After the door is installed in the aerated concrete wall, it must be attached to the frame with powerful self-tapping screws.
Anchors	In this way, only light and narrow structures can be installed. The fastening elements included in the kit must be replaced with anchors for cellular concrete. The further process takes place as standard, according to the instructions for the door frame.

If you plan to install heavy metal doors, then it is better to use adhesive chemical anchors during installation.

• In gas blocks around the entire perimeter, holes are drilled 15 cm deep at a distance of no more than 60 cm from each other and filled with reagent.
• Anchors or threaded studs are arranged in them.
• Additionally, the structure is fastened with self-tapping screws.
• The steel frame or garage hinges are attached at the final stage, when the chemical composition has completely hardened.

Of all the methods for a metal door, the most reliable is installation on embedded fasteners built into the walls during the construction of the structure.

If the opening is strengthened correctly, then the aerated concrete will not lose its integrity and will securely hold the door of any configuration and weight.

1. Equipping the frame for the front door, you need to make a U-shaped frame. Installation of partial (side) fastening is possible only when installing interior structures. Strapping without a top beam does not provide the required rigidity.
2. Fixing the door to reinforcing bars is not acceptable. The porous structure of the block is deformed by impacts and fixation does not occur. The gap under impact load will gradually increase and the box will come out of the span.
3. The placement of entrance doors with the use of framing frames requires additional measures to protect against freezing by means of insulation.

If the design of the door set does not provide for a platband, then screws-anchors or self-tapping screws are used to fasten the box into the opening.

To prevent the destruction of the gas block, the box must be installed so that there is a uniform distribution of the load over its entire area. The position is leveled until the structure is correctly positioned. Wedges can be used to fix the position, after which the structure is fixed with mounting foam.

Articles

Aerated concrete is widely used for the construction of various buildings instead of the usual brick and cinder block. Such a material has many advantages: strength, lightness, excellent heat and sound insulation, large dimensions that speed up the construction process. But there are also some disadvantages. So, in view of the porosity of the material, the installation of the front door in aerated concrete differs from traditional technology.

Preparatory work package

Often, the owners of premises with aerated concrete walls are afraid of the possibility of its destruction due to the porosity of the material structure. It will be easier for intruders to tear out a heavy metal door than to bother opening it. But such a probability is possible only when installing the structure in the traditional way.

Before starting installation, it is important to take care of removing the old door (For information on how to dismantle a PVC window, read the link if this is not a new building, and cleaning the surface of the opening. The blocks themselves also need to be prepared. A common way to process them is to glue the outer surface with a self-adhesive, waterproofing tape But it is better to prime the aerated concrete with a deep penetration strengthening compound, which allows you to reliably protect it from moisture ingress.In addition, the surface of the block itself will become stronger to a depth of 50 mm.

A common problem that you may encounter when installing a door yourself is the mismatch between the size of the door frame and the opening. In almost all new houses, they are made non-standard. But this problem can be fixed.

In the case when it is necessary to reduce the opening, additional laying of the same aerated concrete or other materials (brick, cinder block) is carried out. To expand the installation space, you need a puncher or a grinder with a diamond-coated disc. When adjusting the dimensions of the doorway, it is important to remember that the metal door is installed with a small gap of 20-60 mm.

The main ways to install the front door

When installing entrance doors in aerated concrete walls, there is a possibility of backlash in the holes that are made in the material. During operation, it can increase even more, leading to loosening of the structure. Therefore, the installation of doors by drilling holes with clogging of fittings is not reliable.

Wooden strapping of the opening;

Use of adhesive or expansion anchors;

Fastening to a metal frame.

All these methods can ensure the reliability of the installed door, have a number of advantages and some disadvantages.

The technology of using wooden strapping

This option is suitable for installing massive metal entrance doors, garage swing systems, wing structures, when there are increased shock loads in the areas where the box is fixed to the aerated concrete wall and there is a possibility of deformation. To prevent the destruction of porous material, the door frame is installed on wooden modules or embedded beams or on a frame-pipe. This technology allows you to evenly distribute the level of mechanical load around the entire perimeter of the opening.

The intermediate structures themselves can be made of dense plywood, wooden beams, planed boards. The material must be treated with a liquid antiseptic composition and left to dry completely.

Lightweight structures can be installed on solid or threaded overhead panels or beams, previously buried in aerated concrete. They are fastened in the doorway with special glue with additional fixation with bolts for porous materials. If threaded panels are used, the gaps between the individual slats are filled with mounting foam.

The door frame is connected to the wooden trim with self-tapping screws. If the door is very bulky or heavy, you should make a full-fledged wooden frame from a thick beam. It is attached to the opening with adhesive anchors. After the strapping is completed, a door frame is installed on it.

Mounting the door with anchors

This method is considered the most budgetary, but it is used only for narrow and lightweight structures. Mounting dowels that come with the kit are replaced with anchors for aerated concrete. They are adhesive or spacer.

The working end of the expansion anchor is screwed into the wall. At this moment, it is divided into two parts and makes a strut. As a result, the anchor is securely fixed in the porous structure of aerated concrete. If adhesive devices are used, holes are first made in the wall and filled with polymer resin. The hardened filler securely fixes the threaded part of the anchor in the wall.

Installation of the structure on a metal frame

This method allows you to reinforce the opening with a pile frame, which is formed from metal corners, additionally connected by tape jumpers. This installation technology is considered affordable and the most reliable. For metal doors of standard sizes, it will be enough to make a frame from a 35-45 mm corner. For massive structures, it is better to use corners 50x50 mm.

Step-by-step instructions for installing the front door in aerated concrete using a metal frame:

1. The corners themselves are adjusted to the size of the opening from the gas blocks, 2 sets of segments for the inner and outer sides are required. Each of them should include 2 long and 1 short corner.

2. The cut pieces are placed on the edge of the opening and the end parts are welded. The result will be 2 U-shaped arches that fit snugly against the edges of the opening.

3. Finished arches are fixed to the surface of aerated concrete with anchors. To strengthen the structure between themselves, they are additionally pulled together with tape jumpers. For their manufacture, 3 mm sheet metal is used, cut into the desired segments. Jumpers are welded at the attachment points of the door frame. It is not recommended to install only the vertical parts of the arch to save money. The benefit from this will be minimal, and the design will significantly reduce rigidity.

4. Welded jumpers should be fixed with self-tapping screws to ensure maximum reliability. They should be screwed into the aerated concrete wall in such a way that the caps do not coincide with the holes for attaching the door frame.

5. The box is installed in the finished arch. It is important to check the correct entry of the plumb line. After adjustment, the box is fixed with wooden wedges.

6. Using 15 cm self-tapping screws for metal structures, screwed into the aerated concrete surface through the lintels, the door frame is finally fixed in the opening. For particularly massive structures, dowels can be used. Holes are made in aerated concrete, dowels are installed in them, and self-tapping screws are already screwed into them.

7. Upon completion of the installation, all seams should be treated with sealant and the cracks should be blown out with mounting foam.

8. For hardening and complete setting, it is recommended to leave the structure for 6 hours at rest. After that, the excess foam is removed with a clerical knife, and the seams are once again passed with a sealant.

After completing all the work, it is recommended to adjust the door. This will extend the life of the structure. Even slight distortions of the door relative to the box can affect the operation of the canopies and locking mechanisms.

Conclusion

From the foregoing, we can draw a simple conclusion that the installation of the front door in aerated concrete can be done independently, the main thing is to strictly adhere to the specified technologies and take into account the low mechanical strength of such a building material as aerated concrete.

How to install a heavy metal door in an aerated concrete opening can be found in the following video:

If you liked the material, I will be grateful if you recommend it to friends or leave a useful comment.

Houses made of aerated concrete and foam concrete can be found in any cottage cooperatives. This is due to the fact that these materials are cheap, have excellent heat and noise insulation and can be decorated with various materials. Aerated concrete, decorated with decorative bricks, from a distance is no different from brick buildings. After the construction of the frame and roof, it is required to start internal work. Installing the front door to a house made of aerated concrete is a key step before finishing.

Installation of a metal door in aerated concrete can only begin after preparation. The gas block is a cellular material that crumbles under heavy loads. If intruders want to enter the premises, they will not open the metal door. It will be easier for them to pull it out with fasteners. The preparatory work depends on whether the house is new or old.

If the building is new, you need to mark the passage and cut it out with a large grinder. Next, the surfaces are leveled at the building level. If the house is old, you need to dismantle the box and canvas. The door is removed from the hinges, and the box is carefully detached from the walls and removed.

Important! Do not use rough tools for dismantling. Due to vibration, the integrity of the cellular material may be compromised.

After it is necessary to level the working surfaces. When there are no complaints about the level, the gas blocks must be coated with a primer that will protect them from the damaging effects of moisture. If there is no primer, you can use a waterproofing tape, which is equipped with a self-adhesive part. The primer has a serious advantage over the tape. It strengthens the structure of the material 50 mm deep.

At the preparation stage, it is important to choose in order to know what size the passage should be. If the opening needs to be smaller, it can be filled with bricks or cinder blocks. If you need to increase, a puncher and a large grinder are used.

Materials and tools

You need to start construction work after preparing the tool and consumables. You will need:

1. Hammer, hacksaw for cutting foam and gas blocks.
2. Big Bulgarian.
3. Perforator, screwdriver.
4. Accessories for power tools.
5. Construction level, tape measure, marking devices.
6. Mounting foam, fasteners.

Installation in the aerated concrete opening of the entrance doors should begin after the preparation of everything necessary. Otherwise, you will have to interrupt the process and look for the missing tools.

Methods for installing doors in aerated concrete houses

You can install a door in an aerated concrete house in the same way as in buildings made of wood, metal, panels. However, in this case, the fasteners may loosen over time, and the door leaf will not be able to perform the main task - to protect the room from strangers.

To reliably protect against the penetration of intruders, cold, moisture and noise, it is required to choose non-standard installation methods. There are three in total:

1. Anchor fastening.
2. Installation on a welded frame.
3. The use of wooden strapping.

Anchor mount

It is considered the cheapest and easiest way to install. For fasteners, special anchors are used that are suitable for cellular materials. Anchors for aerated concrete are devices that are screwed into the block. At the moment of twisting, the fastener is divided into two parts and is securely fixed in the wall. To increase the indicators of reliability and strength, an adhesive mass is used. Before screwing, holes are made in the wall, which are filled with glue, and the anchors are screwed into them. After hardening, the polymers securely hold the fasteners, preventing the door from loosening or falling out.

Installation on wooden strapping

Additional wooden strapping is installed in the passages with increased load or when installing heavy door blocks. If there is a possibility that an additional load will be applied to the canvas and the box, wooden elements are installed. It can be individual bars, slats, slats or a box. The latter option allows you to evenly distribute the load across the opening.

Important! Before installing a wooden strapping, it is required to prepare the wood in advance. It must be impregnated with waterproofing and antifungal compounds.

The choice of wooden structure will depend on the weight of the door. If this is an interior canvas made of fiberboard, chipboard, MDF, you can install two parallel bars and fix the anchors in them. However, if we are talking about a heavy metal door, you need to assemble a full-fledged wooden box, which will ensure a secure fixation of the door system.

Installation on a welded frame

It is considered a simple, reliable and durable way to strengthen the door block. It implies the installation of a box and canvas on a welded frame. It is made of iron corners and lintels that connect individual elements.

Step-by-step instructions for collecting a metal frame:

1. First of all, the dimensions of the passage are taken. They cut corners. One set should go to the outside, the second to the inside.
2. When the corners are prepared, you need to weld two frames. For this, metal elements are applied to their places and welded at the ends to each other. If the work is done correctly, you should get two rectangular frames.
3. After the frames are made, it is necessary to make metal jumpers that will hold the rectangular structures together. To do this, you need a thin steel sheet (3 mm).
4. The frames are fixed to the wall with aerated concrete anchors and welded using metal jumpers.
5. Additionally, the jumpers are fixed to the cellular blocks using self-tapping screws.
6. Next comes the installation of the door block. For this, 15 cm self-tapping screws are used, which must be screwed into the walls through metal lintels.
7. When the door is level and not skewed, it is possible to fill the empty spaces between the aerated concrete and the box with insulation or sealant.
8. After mounting along the contour, the door frame must be foamed with mounting foam.

Features of installing heavy doors in aerated concrete

When installing heavy door blocks, builders recommend using adhesive-filled anchors. To do this, you need to pre-drill holes 15 cm deep in the cellular blocks, and fix the spire with anchors in them. Next, the box is fixed to the prepared surfaces using self-tapping screws.

If a person plans to do the work on his own, he should use the recommendations of specialists:

1. Do not install the door on metal bars that have been hammered into blocks. During clogging, the cellular structure is crushed and an initial backlash is formed. At first, it will not be noticeable during the operation of the door, however, over time it will become larger and violate the stability of the door.
2. The question often arises of how to install an entrance door in an aerated concrete house if the wall is insulated. To do this, you need to cut the old heat-insulating material 20 cm from the box in all directions. After installation is completed, a new insulation must be installed.
3. Be sure to additionally insulate the metal strapping. They quickly freeze and contribute to the ingress of cold into the room.
4. During the installation of insulation, you must constantly check with the building level and plumb line.

Door leaf adjustment

Any person can adjust the door system without additional skills. For example, you can get rid of squeaks by lubricating moving elements. To do this, use a syringe filled with engine oil or WD-40.

If the sounds have not disappeared, you need to carefully inspect the fasteners on the box. Sometimes the mounting bolts, self-tapping screws or anchors are not “recessed” enough, and the canvas rubs against them when closing and opening. You need to tighten them up.

To get rid of a slight skew, you can use a hexagon. The new doors have the ability to adjust the position of the leaf vertically and horizontally. Usually the adjustment elements are located in the loops.

When installing doors in houses made of aerated concrete or foam blocks, special attention must be paid to the cellular structure of these materials. It does not allow the use of classical mounting methods. You need to choose one of three installation options and carefully carry out the work.

The technology for installing an entrance metal door in an aerated concrete house is somewhat different from the traditional method of installing such structures. These features are due to the specific qualities of the materials from which the door itself is made and the building is erected. Having a cellular structure, aerated concrete is a building material that is light and rather fragile, and the weight of a standard metal door sometimes reaches one centner. Due to such a contradiction, a door installed in the usual way, under the action of even a slight effort, can simply fall out of the doorway.

That is why experts advise installing narrow (up to 1 m) metal doors in aerated concrete houses, and mounting them using special fasteners or additional structures.

Methods for installing doors in aerated concrete houses

Installation of doors in gas-block buildings can be done in one of the three most common ways, namely:

• on special expansion or chemical anchors;
• to the wooden trim of the doorway;
• to a welded metal frame.

Each of the above methods has a number of advantages and disadvantages, which will be discussed further.

Method one. Anchor fastening

This simple and low-cost method is acceptable only for the installation of lightweight and narrow doors that do not experience large operational loads. When using this method, the fixing dowels supplied with the doors are replaced with special anchors for cellular concrete, which, depending on the principle of operation, can be expansion or adhesive.

When screwing into the wall, the working end of the expansion anchor splits in two and becomes completely flat, as a result of which the bolt is fixed in the loose structure of the gas block. Under adhesive anchors in aerated concrete, holes are pre-drilled, which are filled with polymer resin. After hardening, such a composite securely holds the threaded part of the anchor in the wall.

With the help of such anchors, the turf box is fixed in the wall opening in a standard way.
To reduce the absorbency of aerated concrete and seal its structure, before installation, the surface of the opening is treated with a deep penetration waterproofing primer.

Method two. Installation on a wooden strapping.

In the case of installing a massive steel front door, double doors or garage doors in places where the box is directly attached to the wall, aerated concrete will experience significant deformation and shock loads, as a result of which its fragile cellular structure will gradually collapse. To prevent crumbling of gas blocks under the heads of anchor bolts, door frames are mounted on wooden panels, strapping frames or embedded beams, which provide a more even load distribution around the entire perimeter of the doorway.

Such intermediate structures are made of wooden beams, thick plywood or durable planed boards. Before the construction of the strapping, the wood is impregnated with a liquid antiseptic and dried well.

Lighter doors are mounted on beams buried in the surface of aerated concrete or on solid or intermittent (gathered from separate segments) overlay panels cut along the thickness of the walls, which are laid in the doorway on a layer of special glue, and then additionally fastened with bolts for cellular concrete. In the case of installation on separate pieces of boards, the empty spaces between the pieces of planks are filled with rigid mounting foam.

The metal door frame is attached to the finished wooden frame with powerful self-tapping screws. The heaviest and bulkiest doors are mounted on a full-fledged strapping frame, constructed from thick wooden beams attached to the walls of the opening with adhesive anchors, on an epoxy basis.

Having completed the arrangement of the strapping, garage hinges or a metal front door frame are attached to it.

Method three. Installation on a welded frame.

With this method of installation, the doorway is reinforced with a double welded frame, assembled from steel corners, for strength, pulled together with tape metal lintels. Since this method of fastening, due to its availability and at the same time reliability, is the most common, we will describe the technology of its execution in more detail.

The technology of mounting the front door on a metal welded frame

For a metal front door in the standard version, it will be enough to weld an installation frame from a 35 or 40 mm steel corner. For a massive reinforced steel door, it is better to take a 50x50 mm corner.

1. The corners are cut to the size of the opening - one set of two long and one short pieces is made for the outside and the second is the same for the inside.
2. The corners cut in this way are placed on the edges of the opening, and their adjacent ends are welded. As a result of this operation, two U-shaped arches are obtained that fit snugly against the ribs of the doorway.
3. The arches are fixed with special anchors to aerated concrete and, for strength, are pulled together by short jumpers cut from 3 mm sheet metal.
4. Jumpers are welded to the corner frames in those places where the door frame will have to be attached to the opening.

Tip: Some homeowners, wanting to save time and money, try to install only the vertical parts of the frame. You shouldn't do this! The benefit from such savings will be extremely small, and a structure without top beams will lose its rigidity.

Metal frame for doorway

1. For greater reliability of fastening, the welded jumpers are also attached to the wall with self-tapping screws, screwing them in so that the caps do not coincide with the mounting holes in the door frame.
2. A door frame is inserted into the finished frame, controlling the verticality of the installation with a plumb line. Having corrected the position of the box, it is fixed in the welded frame with wooden wedges.
3. Next, the box is fixed in the doorway with powerful 15-centimeter metal screws, which are screwed into aerated concrete through steel lintels. If the doors are quite heavy, for greater reliability, the self-tapping screws are not screwed into aerated concrete, but into special dowels, under which holes are pre-drilled in the walls.
4. After installing the box, all seams in the structure are coated with sealant, and the slots are blown out with dense mounting foam.
5. After hardening, the excess foam is cut off with a construction knife, and the seams are once again treated with sealing mastic.

Tip: some craftsmen, wanting to quickly complete the work entrusted to them, offer the owners to fix the box on the rebar pins driven into the walls. You should not agree to such propositions! This method of installing doors, although not very desirable, is at least partially acceptable only for brick houses. A steel bar hammered into soft aerated concrete crushes its fragile wall structure. As a result of a violation of the structure of the wall material, the reinforcement cannot be reliably fixed in the thickness of the gas block. The small play formed at the beginning of the installation work will increase with each slam of the door, and this process will continue until the box is completely out of the doorway.

All of the above methods of installing an entrance metal door are good in their own way, but nevertheless, the most reliable fixation of the door frame is provided by special steel fasteners embedded in the walls at the stage of building a house from aerated concrete.