To most people, demolition work seems quite straightforward. All you have to do is knock the building down and haul away the debris. Sounds easy, right? Actually, there’s a lot more to it.
Demolishing a building of any size requires careful planning, preparation and execution in order to be accomplished safely and efficiently. For these reasons, it is recommended to leave demolition work to trained and experienced demolition workers, rather than doing it yourself.
Also, in many cases older structures contain potential hazardous materials such as asbestos, which can be a major health risk if it is not removed properly before demolition begins. If you have plans to demolish an old building, contact Certified Asbestos for asbestos testing and asbestos abatement services before any workers get put at risk.
This short guide will shed some light on the planning that goes into a demolition project, as well as different demolition techniques and how they are applied to different types of structures.
The Demolition Process
Before taking down buildings, demolition companies must take many different factors into consideration. Different approaches to this type of work exist because conditions can vary so widely from one building to another, and so each demolition project must be considered in its own right, with customized planning and pre-demolition preparation.
In general, large-scale demolition projects involve the following steps:
Building Survey / Inspection
Structures slated for removal must be thoroughly inspected to identify all the potential hazardous materials that could pose an issue for demolition workers or the surrounding community. This information helps inform the best demolition technique for the situation and plays a huge role in determining the demolition plan.
Pre-demolition surveys take into consideration things like:
- The type of building and its usage
- The kinds of building materials the structure contains
- The presence of toxic, flammable or other hazardous materials, such as asbestos, lead, mercury, PCBs, ozone depleting substances, or petroleum contamination
- Shared infrastructure with adjoining buildings
- The impact demolition work will have on the surrounding area, such as the effects on pedestrian or vehicular traffic, noise, vibrations, as well as dust and debris
Removal of Hazardous Materials
Asbestos minerals are the most commonly found hazardous material in older residential and institutional buildings. In other building types, petroleum-based contaminants and other flammable materials also pose a serious risk.
Removing these materials should be left to specialized, professional services in order to make the job as safe as possible.
This detailed plan shows exactly which elements will be destroyed, the demolition technique to be used and how much debris will result.
Demolition workers, supervisors, heavy equipment operators and engineers must be on the same page when it comes to safety planning and precautions. Safety planning is an important element of the permit application process in many jurisdictions.
Certainly, the most spectacular way to take down a building, implosion involves using explosives to destroy a building’s primary structural components, which causes the building to collapse. But this approach only accounts for a very small percentage of all demolition projects, as it is only used in exceptional circumstances for large buildings.
Demolishing most homes and office buildings is accomplished through the use of heavy machinery. Excavators can be equipped with a variety of specialized tools, like shear attachments, crushers and hydraulic hammers, to dismantle the structure from the top down. At the same time, demolition worker crews on the ground use tools, like sledgehammers and crushers, to reduce the pieces to rubble before having them removed.
Wrecking Ball Demolition
Wrecking balls are a seldom-used piece of equipment in modern demolition projects, but they remain the iconic image that most people picture when they think of a demolition project.
Wrecking balls can knock down structures quite quickly and cheaply, however, they also cause a number of health and safety concerns, which is why they are considered outdated.
This method is also known as “hand demolition” or “deconstruction” because it entails removing specific elements, rather than destroying the structure entirely. This is the preferred approach by renovators in the construction industry, as it is conducive to remodelling, upgrades or expansion. Also, it favours recycling and reusing certain materials during the construction work, which is why it has become the method of choice for environmentally conscious building owners.
The Demolition Process for Residential Sites
For relatively small demolitions on residential sites, the project is usually carried out in five steps.
- Building survey / inspection
- Permit acquisition
- Disconnection of electrical / gas / water services
- Debris removal
Houses and foundations are usually demolished using either excavator demolition, selective demolition, or a combination of the two.
The cost of demolishing a home with foundations will vary according to the size of the structure, the building’s materials, the location of the building and the demolition method. Also, weather conditions can play a major factor, as they can cause delays and cost increases.
Demolition Prior to Renovations
For these projects, selective demolition is normally used, except in cases where there are plans for a large addition or expansion.
The total costs of these projects depends on the particular characteristics of the building and the complexity of the work required. For historic sites, the need to preserve certain elements forces workers to proceed with caution, so these jobs take longer and cost more than a conventional demolition.
If the area to be demolished contains plumbing, load-bearing walls or asbestos, the costs can quickly escalate.
For in-ground swimming pools, homeowners have two options. Either to excavate and remove the pool completely or to remove the top portion of the pool and fill in the area with the debris. In either case, pool removals are normally carried out through excavator demolition. Complete excavations are far more expensive than a partial excavation/fill in approach, which is why they are rare.
To demolish concrete patios and driveways, excavator demolition is the method of choice. For small areas, demolishing by hand with the help of a jackhammer is a viable alternative.
The cost of these projects varies according to the amount of concrete for disposal, dump site fees and transportation fees.
Contact Certified Asbestos Before Your Next Demolition Project
As you can see, there is no one-size-fits-all approach to demolition projects. Demolition methods vary significantly, depending on many factors. But the common denominator for demolitions of any scale is that safety precautions are paramount.
If you are concerned about the possible presence of asbestos on your job site, Certified Asbestos provides complete asbestos testing and remediation services. Contact us today!