The construction industry began using asbestos in the early 20th century because of its heat resistance, durability, and insulating properties. However, as health risks associated with asbestos came to light, the US Environmental Protection Agency (EPA) drastically limited its use.
Yet, according to a 1988 study by the EPA, around 20% of public and commercial buildings in the US still contained some asbestos material, either in insulation, plaster material for acoustics, or in flooring. Here are some options contractors can consider when dealing with an asbestos-containing floor.
Asbestos is a general name given to naturally occurring silicate materials composed of long, thin fibers. The material is highly resistant to fire, has excellent insulating properties and the structure of its fibers make it strong, durable, and flexible. These qualities, as well as its cost-effectiveness, made asbestos a popular material in construction applications.
When working in buildings constructed before regulations limiting the use of asbestos, contractors should be careful to ensure asbestos is managed properly. This is because when asbestos is damaged, the small fibers released can be inhaled and lead to serious health problems, such as asbestosis or mesothelioma.
Reviewing The Floor
Before starting any floor preparation job, contractors will survey the site to establish the type of covering they must remove, the condition of the slab or subfloor, and whether the desired new covering will meet the customer’s expectations.
During this initial stage, the existing floor covering and when it was manufactured could quickly indicate the presence of asbestos. Beginning in the 1920’s up to the 1980’s, manufacturers used asbestos in materials such as vinyl composition tile (VCT). These floor coverings were often popular in large commercial buildings such as supermarkets because they were long-lasting and easy to maintain. A range of other building materials manufactured before the 80s could potentially contain asbestos, and it is not always obvious from the initial assessment. So, when planning work in older buildings, contractors should liaise with the facilities manager before arriving on site to request an asbestos management survey from an expert.
With the asbestos removed or safely sealed, contractors can grind and polish the floor ready for a new covering. Take the time to select the right tooling to achieve the required concrete surface profile.National Flooring Equipment
Decisions, Decisions
When preparing a floor that contains materials with asbestos, inform your customer of two choices: remove it or cover it. If the customer chooses to have the asbestos removed, this must be performed by an asbestos mitigation company that specializes in containment or removal and not the flooring contractor. A specialist team will know the ins and outs of the protective measures such as securing the room to seal the space, using specialized equipment to remove the asbestos, and using high powered vacuums and abatement equipment to remove related debris. Once the asbestos has been fully removed, contractors can prepare the concrete substrate and lay the new covering as normal.
While this approach effectively removes a potentially dangerous material, the contractor will need to manage customer expectations. Asbestos removal can be time-consuming and costly — also, the removed material may also go to landfill, moving the problem elsewhere.
In most floor preparation cases, it is best practice to remove any existing floor material before laying new a covering. However, if the existing floor contains asbestos, the risks can outweigh the benefits. Additionally, covering asbestos-containing floor material is typically a more cost-effective alternative to asbestos removal, and there is no legal obligation to remove it.
This approach involves encapsulating the existing VCT by pouring a layer of cementitious material around 2-2.5 in. (50-75 mm) over the existing floor, to create a new substrate, concealing the asbestos containing material and preventing the release of dangerous fibers into the air. To ensure they follow best practice, contractors can consult with asbestos mitigation experts for support.
Once the new layer is set, contractors can grind and polish the floor ready for a new covering. Just like any grinding application, contractors should take the time to select the right tooling to achieve the required concrete surface profile (CSP) for the new covering. This will still deliver a durable, low maintenance flooring option that could be more cost effective and sustainable for the facility.
The prevalence of asbestos in 20 per cent of public and commercial buildings in the US means it is important that all flooring contractors understand the risks associated with asbestos, and best practice for minimizing them.
