Having a protective and waterproof coating on the floor is very important to ensure that the overall cost efficiency and integrity of the car park structure is kept in tact. However, there are a number of other ways that car parks can be properly protected.
For this reason, we are going to take a look at some of the approaches that are used and the things that need to be considered.
The Importance Of Protecting Deck Surfaces
Whilst a concrete slab floor that is completely solid may at first glance appear to be robust enough to withstand the stresses and strains that come with being in a car park; it is not as actually indestructible as you may think it is. This is because in a car park setting, the material is actually subject to a considerable level of stress. For instance, with modern day cars now weighing in excess of one ton – some even more than this – the impact from these is considerable and at any one time there may be hundreds of vehicles parked on the surface all at the same time. In addition to all of this weight, car park decking is also subject to the impact from the likes of de icing salt, brake fluids, lubricants, exhaust fumes, etc. etc. When out in the open, such as atop of a multi storey car park, the decking is also exposed to ever changing weather conditions, such as snow, ice, UV radiation, temperature changes, rain, and wind.
How This Impacts On Concrete
With these many different factors at play, concrete eventually erodes away. The impact of harsh and changing weather conditions mean that the material eventually becomes porous, allowing water to get in and cracks to appear. Over time the like of the de icing salt and water will make its way deep down into the reinforcement inside of the concrete and work to speed up the process of corrosion. In combination with the impact and stress from all of the heavy vehicles, the integrity of the concrete starts to become compromised, questioning the sheer durability and safety of the car park structure. This is why a proper waterproof and protective coating is so important. Where one is used, the overall durability of the car park is greatly improved – thus increasing its life span.
Characteristics Of A Protective Coating
A protective coating used in a car park setting needs to have specific crack bridging qualities, along with a certain level of general resilience. This is because it needs to be able to handle the stresses that come with heavy vehicle use. Any open areas, such as the top deck, will inevitably be subject to some cracking over time, which is why any protective coating used must be capable of bridging cracks and so stop water and other potentially harmful chemicals from getting into the concrete and causing even further damage to it. Other requirements include the need for it to be slip resistant, the be able to visually outline bays, and to indicate directional markers. Although this all sounds very simplistic, it is actually difficult to find a coating that can do all of these things at the same time.
Protective Coating Layers
In order to work like it should, the protective coatings that are used in car parks need to comprise of anywhere between 2 and 4 separate layers, each of which have their own different properties. These are called the top cost, the wear coat, the membrane, and the primer. Despite being the thinnest layer, the top coat plays a very important role in providing full protection to all of the other layers and is able to withstand a range of weathers and chemicals. It is the way in which these differing layers are combined that define who durable and efficient the protective coating is – it also impacts on how tiresome it is to install also. With each and every car parking structure being so very different, it means that when it comes to protective coatings, there is no one size fits all solution. Each individual project must be analyzed separately in order to see exactly what the requirements are in that case.
Functions Of Each Layer
The number of and type of layers used is completely dependent upon the project requirements and the exact application of the protective coating. However, what the coatings do typically consist of are a range of top coats, wear coats, membranes, and waterproofing. Together these things for a full and complete protective system. Each and every layer of the finished system serves a different purpose. For example, in a car parking structure that has multiple different storeys, the requirements differ from level to level. Some of the most important parts of these are seen below…
- Ramps between levels get lots of abuse and so where it can be done, a highly resistant system of nothing less than four layers needs to be implemented on them.
- Where the very bottom level is concerned, the substrate that sits directly below the concrete needs to be seriously considered. As a result of this, it may be the case that it needs extra waterproofing in order to stop earth moisture or groundwater from building up and causing damage. Where this is so, a system of between 2 and 3 layers is required.
- Mid level decks are typically enclosed areas and so do not come into direct exposure of different weather conditions like rain or sun. However, in order to increase the overall safety of the structure crack bridging and durability are both required via a system of between 2 and 3 layers.
- On the very top deck, the protective coating needs to be able to withstand a range of different impacts from the environment, in addition to have crack bridging capabilities. Therefore, a system with 4 layers is required for this part of a multi storey car parking structure.
Additionally to the above, other general requirements that are relevant to all levels of a car park include skid, wear, and abrasion resistance.