Demolition and dismantling of buildings and structures

Recommendation points

• The issue of the expediency of demolition or dismantling of a building
• Elemental disassembly
• What to do first
• Getting started: dismantling the roof
• Working with slabs
• Dismantling the walls
• Stairs, columns and pillars
• The last stage: the foundation

Buying a land plot with a house that does not suit the new owner for some reason, the desire to build housing with modern architectural solutions, the need to get rid of dilapidated real estate – these are only some of the reasons why you will have to resort to dismantling and demolishing the old building. Let’s figure out whether it is worth demolishing the old house at all, and if so, how you can do it yourself.

The issue of the expediency of demolition or dismantling of a building

In the process of deciding on the demolition of a building, the advisability of such a radical measure should be considered. It is necessary to carefully, preferably with the involvement of specialized organizations or specialists in the field of construction, examine the structure for the possibility of its reconstruction or completion, other alternatives to demolition and construction of a new building.

The fact is that often the destruction of an existing building and the construction of a new one “from scratch” do not justify themselves either in terms of financial costs or in terms of the necessary labor costs. As a rule, labor costs for dismantling a building by hand are practically comparable to the volume of work for the construction of a new facility of similar complexity, and in some cases even exceed them..

At the same time, the results of numerous engineering surveys of buildings of various types have demonstrated that high-quality buildings at one time in general have a sufficiently high stability and bearing capacity, in general, they preserve welded seams and the integrity of embedded parts..

For example, if concrete with a high cement content was used during the construction of an object, taking into account their long-term hydration, the strength of the foundation of the house may be 30% higher than the design indicators, and the satisfactory condition of other structural elements of brick and large-block buildings makes it possible to carry out a complete reconstruction and even erect additional floors or add-ons.

Elemental disassembly

Let’s say the decision to dismantle the building has been made. How do you implement it? The liquidation of residential and other objects in the private sector is carried out by dividing the structural elements of the structure into parts or, at the decision of the owner, in case of a shortage of time and labor, by mechanical collapse with heavy construction equipment. Other methods of demolition, including blasting, thermal or electrohydraulic impact, are usually used only at large residential and industrial facilities and only by powerful specialized companies..

Despite the fact that the dismantling of structures element by element takes much longer and is often more expensive than mechanical scrapping, using the first method, you can get ready-made components and structures for the construction of a new building – wall panels, flooring and partitions. In the future, not only whole structures will come in handy, but including brick and concrete battle, recycled rubble, high-quality wooden components.

In this case, any element is first freed from bonds, and heavy monolithic structures, if dismantling is impossible, are mechanically destroyed into smaller fragments. So, let’s consider each stage of work in more detail..

What to do first

Before dismantling a building, preliminary preparations must be made. First of all, you should turn off and drown all engineering communications without exception..

Attention! In a number of cases, networks of not only local, but also main values ​​can pass through the site – power supply, sewerage and storm water, water, heat and gas supply systems, communication and television cables.

If such highways are really located on your site, you need to decide with the network operators the issue of the safety of demolition of the building for the highways and, if necessary, request the transfer of communications to other zones.

After the completion of work with communications, it is necessary to equip the fencing of the territory on which the dismantling will be carried out, to deliver the necessary equipment and tools, equipment for temporary fixation of structures during the dismantling process.

Getting started: dismantling the roof

Remember:the main principle of the element-by-element dismantling of buildings is in its order – always the reverse of the construction scheme of the object, that is, you need to start from the roof.

Immediately before dismantling the roof, you must remove all wiring, antennas and other installed elements from it. After that, the attic floors should be fixed..

Important! If a roof with a slope of more than 20 degrees is disassembled, cornices with a projection of more than 0.3 meters from the walls, you need to use safety belts.

Dismantling of buildings should start from attic floors, while if the height exceeds 1.3 meters, use a scaffold with an emphasis on the floor beams. Do not put the scaffold on the backfill, roll-up boards and other elements of the inter-girder space. Hanging rafters in the working position should not be disassembled, before that they must be lowered onto the attic floor.

Working with slabs

Overlappings need to be destroyed only from top to bottom – after disassembling the structures of the upper floor and completely removing the dismantled elements. If there are no floors, but it is necessary to remove the backfill or roll-over, temporary flooring is placed with a width of at least half a meter. Moving on panel boards is allowed only with fences and safety belts.

Wooden floors between floors are not completely dismantled – at first every fourth beam is left to ensure a stable position of the walls. The left beams are dismantled last. If necessary, you can strengthen the beams with girders and uprights from below.

If we are talking about floors made of brick or reinforced concrete, to prevent the collapse of the structures, temporary support is installed with a reliable base and with a solid flooring. Dismantling of ribbed reinforced concrete slabs for safety reasons should start with secondary beams.

Disassembly of brick vaults is allowed only after the installation of struts, which will take the horizontal load from adjacent vaults. Such spacers must be placed on the lower shelves of the beams in a straight line, while the step should be up to three meters.

Dismantling the walls

Walls can be disassembled in different ways, the most common of which are: using a punching tool – pneumatic or electric, impact destruction or rolls using heavy equipment.

Before dismantling the walls, you need to do the following work:

• dismantle internal engineering networks and equipment;
• remove the glazing of windows;
• disassemble door and window fillings.

Attention! Any grooves or grooves cannot be made deeper than a third of the wall thickness, and no more than 150 millimeters in width..

The undercut should be done exclusively in the absence of a vertical inclination of the structure in its direction. If the wall will be demolished by the shock method, then you must first protect an area with a width of at least a third of the building height.

Stairs, columns and pillars

Ladders, like other structural components, must be disassembled from top to bottom in the course of dismantling walls and floors. In this case, the stair railings need to be dismantled dearly as the stairs themselves are disassembled. Disassembly can be carried out only within one floor at a time.

When working with columns and pillars, the cutting of these elements must be carried out after their slinging. At the same time, the ways in which the slinging is performed must be guaranteed to exclude the accidental fall of pillars and columns. If the latter lose their stability, they must be temporarily strengthened before dismantling..

The last stage: the foundation

As a rule, there are no special requirements for dismantling the foundation – the order of work at this stage can be arbitrary. It is not recommended to perform deliberately unsafe actions – for example, walk through the openings in the foundation or feed tools through them.

When dismantling, you need to monitor the condition of the soil slopes. It is impossible to be in the zone of possible shift or collapse of the structure, especially in cases when there is a road with heavy traffic nearby.