How to demolish an existing building or parts of an existing structure


Among the most common building activities over the past few years are renovating and expanding existing properties, whether they are of a commercial or private nature. One of the most demanding phases in any renovation or restoration is demolition, whether we are talking about a wall, flooring or any other structural element. Safety is paramount as are the right equipment and meticulous attention so that the stability of the structure is not compromised, surrounding finishes are not damaged and any supporting elements are not weakened.

Before we look at the demolition stage, let’s take a step back and take a quick look a fundamental phase that will set the scene for a successful project.

When demolishing a building safety is paramount as are the right equipment and meticulous attention

Clear, accurate designs

You will most often begin with a design of the current state of the building and its existing spaces. From there, you introduce all the modifications you wish to make, including new walls and any openings, until you have a complete plan of how you envisage the new iteration of the building.

To ensure complete documentation of all necessary aspects, covering every intervention required, drawings that compare both the current and proposed structures will be requested. This is done by superimposing them one over the other and the point of this is to clearly explain all that is needed to be done. Three colours are used in this stage. Grey or black indicate what should remain unaltered, yellow indicates elements that will be demolished and any openings that need to be eliminated, whilst red is used to show what needs to be built or any hollows to be filled.

Before beginning the demolition phase, it is always good practice to scrutinise the design closely, even if it all seems clear.

Choosing the right equipment

To demolish in a fast, efficient and safe manner the best tool to use is a demolition or jack hammer, complemented by other tools depending on whether you need to be more precise or if you want to break up large pieces. These generally include the following:

  • Mallet
  • Chisels (usually a variety of different shapes and sizes)
  • Sledgehammer
  • Jackhammer and drill bits

Safety first and foremost

Before embarking on a demolition, make sure that the site is safe, with such simple precautions as turning off water, gas and electrics. This should be done by specialised tradespeople, most probably the same group who will be responsible for organising the plumbing and electric frameworks.

Let the demolition commence!

To tear down a partition wall or wooden floor, start from the top, breaking the first rows of bricks then proceed row by row until you get to the bottom, taking care to neutralise any sudden toppling of the entire wall.

If you do not approach a demolition in the right way, not only is there a high risk factor for the crew, but you may also cause irreparable damage to the core structures, particularly in apartment buildings where an intervention here, another one there over the years may have altered the overall structural balance.

Keep it clean

Once the demolition itself is complete, the work doesn’t stop. It is important to avoid excessive accumulation of debris on site, but if this is not possible, ensure that any waste materials are distributed in appropriate places and containers, without creating potentially dangerous weight loads on pillars, beams and the like.

To help prevent dust taking over not just the demolition site but also surrounding areas, you should hose down the space with water every now and then. Finally, break down all the debris and sort it into its different types before removing it to landfill sites or similar.


Images taken before 11 March 2020.