What are the principles and methods of partial and total destruction of the building?

Any action that causes materials or parts to be removed from the building or to be reconstructed, renovated, repaired, or restored, is included under the demolition set. As we said above, partial demolitions are for reconstruction and general for renovation. Determining when partial or total destruction should be done depends on several factors: ▪️ To what extent is the building worn out? Is it possible to rebuild? Is it economical and safe to rebuild it? ▪️ In terms of costs, is it better to do reconstruction or renovation? Is the area where the building is located allowed to be renovated?

Sometimes it happens that the building is so worn out that the renovation does not provide enough strength, or the costs are so high that it is preferable to renovate or replace the building. Therefore, it is very important to know the space and structure before carrying out the demolition. Since demolition and renovation require a permit, you must research before the demolition to see if renovation is possible in the area and whether you will be granted a permit or not. If the goal is to rebuild, the destruction can include from removing a few tiles to moving the walls.

General demolition is usually done for the old buildings and new buildings are built in their place. In Iran, usually a building with a life of 20 years and above is considered almost a junkyard, but in other countries, even 80-year-old buildings are renovated and reused. In any case, if the wear and tear of the building is to such an extent that its use is unsafe, difficult and the cost of reconstruction is not affordable, it will be demolished. Usually, the value of these buildings is much higher than the non-climbing buildings.

Partial destruction that is mostly done in reconstruction can have different dimensions; Demolition of floor and wall for plumbing and installations, replacement of ceramic tiles, etc. or opening up the space. Because usually in the old plans, most of the houses were made of many rooms and the spaces were mostly enclosed and closed, today's interior design wants to have spaces with an open and free plan, so the walls can be removed or moved. Of course, this issue requires expertise, why?

There are two types of walls in every building; Carrier and non-carrier. Bearing walls bear the weight of the roof and floors and transfer it to the foundation, so their destruction can lead to the collapse of the building. All the external walls of the building and some internal walls are load-bearing. So, if you are going to destroy the load-bearing wall, you must first build support for these walls with the help of structural calculations and an expert; Horizontal beams and vertical columns. Demolition of non-bearing walls is less troublesome because they do not play an important role in the structure. You can easily destroy them within one or two hours with a sledgehammer, etc., but there is a point that you must specify the walls and parts you want to destroy before destroying them in order to prevent additional destruction. Remember that there are usually wiring and pipes in these walls and they should not be damaged during demolition.

Demolition can be done in different ways that depends on the environmental conditions of the structure and surrounding buildings, structural system, available equipment and budget, and most importantly, expert opinion; The following are among the most important methods of building destruction:

With the help of a skilled and experienced workforce, it is done with utmost care, which usually costs less and leaves us with more reusable materials. It has less environmental effects, but certainly the work speed is lower. For manual destruction, you must start from the highest floor; First the floors, then the secondary beams, main beams, columns and shear walls and finally the foundation.

It is mostly related to mid-rise and high-rise buildings. The short arm machine is moved to the highest floor with the station, of course, first the power of the floor must be controlled to hold these machines and the demolition operation is carried out.

Like the previous method, of course, due to the long arm of the hydraulic machine, the demolition work is done from the outside of the structure, as a result, it is faster and less expensive because there is no need for strengthening. They mostly use this method for unsafe and dilapidated buildings.

One of the oldest methods that is almost not used today and they hit the building using a steel ball attached to the arm.

A completely specialized method that must be done with very precise calculations, planning and knowledge and experience. Because it affects the surrounding environment, there should be investigations of the environment. The effects of the destruction of this method may need to be cleaned for several months and the noise pollution is also high.

▪️ The electricity of the building should be cut off and the meter should be moved ▪️ Gas branches of the building should be cut off ▪️ Water cut in the building Open all equipment and valves ▪️ Creation of privacy around the building according to the municipal rules ▪️ Separating windows, openings and frames Paying attention to the type of skeletonization and separating their different materials ▪️ Proper loading and transportation of construction debris Filling worn-out wells with lime Building insurance before demolition and signing a legal and documented contract with the contractor ▪️ Use of skilled and experienced workforce with technical and official certificates