Car parks feature concrete decks which get exposed to various damaging influences and require robust protective decking systems to ensure their safety and functionality. This means that car park owners and their construction consultants have to assess the condition and needs of their car park structures in order to choose the right protective system to fit. At TPS360 we’ll walk you through the entire process and select, specify and then proceed with the right car park decking system to suit the needs of your structure. 

Where to start The most important things car park decking systems need to prevent, in both new constructions and when refurbishing existing car parks, are water ingress (which can compromise structural integrity) and slip hazards (compromising personal safety). Special attention and distinct treatment needs to be given to certain areas including ramps, turning circles, exposed decks, intermediate decks and below ground decks. 

At TPS360 our protective car park decking includes resin-based systems, including epoxy, polyurethane, and acrylic, due to their protective and aesthetic benefits. These systems are typically applied in thin layers and may include aggregates for enhanced protection and appearance. When choosing the right system and approach we first consider whether we are planning to protect a new or an existing construction.  

New car parks In new constructions, the decks will tend to be flat and level and typically clean and therefore can be easily prepared to accept a protective surface treatment (vacuum blast cleaning is usually the preferred method). Once the decks are prepared, waterproofing and wearing systems can be applied at a thickness of anything from 1mm to 6mm (dependent on requirements) to obtain maximum service life and minimum periods of closure for maintenance, all at the lowest overall cost.  

Existing car parks Before any deck coating works can begin on an existing car park, it must be deemed to be structurally sound, as determined by a professional Condition Survey and a Structural Engineer’s Assessment. Then, any existing problems such as cracks need to be dealt with. After this, more extensive mechanical preparation will be required (still using vacuum blast cleaning technique) and possibly thicker surfacing systems to ensure durability. As a result of the increase in effort and resources required to provide a uniform surface, overall costs will be higher, but these are offset by the increase in longevity of the overall structure. 

As you can imagine, there are going to be a number of stresses on the car park decking, all of which are taken into consideration when we install a resin-based system. It will have to accommodate the following stresses to prevent damage and maintain its structural integrity and appearance: 

• Traffic-induced vibrations and loading. Dynamic loading and vibrations potentially increase movement across construction joints and decks necessitating the use of crack-bridging systems. 
• Thermal movement and shock from temperature changes and weather conditions mean that chosen surfacing systems must accommodate for rapid temperature changes as well as expansion and contraction of movement joints. 
• Mechanical wear from vehicles increases mechanical wear and abrasion, particularly on car park ramps and turning areas, heightening potential damage and impacting joint arrises and drainage connections, necessitating appropriate skid and abrasion resistance and that surfaces be level and repaired as needed before applying deck coatings. 
• Water and de-icing salts can severely damage unprotected concrete, leading to slippery conditions, degradation of concrete and steel reinforcements, and electrical failures, necessitating the use of specialised, crack-bridging waterproofing and wearing systems to prevent ingress and ensure long-term structural integrity and durability. 
• UV radiation/ sunlight aggressively deteriorates and ages car park deck sealants and waterproofing systems, leading to various material-specific issues like discolouration and cracking, thus underscoring the need for clearly defined UV resistance and performance criteria when selecting surfacing for exposed or partially exposed decks. 
• Automotive Chemical Spillage such as highly aggressive hydraulic oils, require confirmation of the proposed deck coating system’s resistance to these chemicals that can also damage concrete. 

Once we have taken all of the above into account, in order to correctly select, specify and then proceed with the correct car park decking system, we have to consider the following: 

Joints We need to verify whether the deck’s movement joints will accommodate thermal and structural movements and assess how the deck’s construction joints have been formed and treated to see whether additional pre-treatment and sealing are necessary. 

Drainage We ensure that the deck has adequate rainwater collection and drainage systems in place, that they are integrated and sealed with any waterproofing membranes and check for evidence of water ponding due to insufficient drainage slopes. Then we consider corrective measures like installing cement or resin-based screeds to mitigate future risks and structural ingress. 

Surface Permeability Requirements For decks at or below ground level with an intact damp-proof membrane, any new waterproofing and wearing surface must be both waterproof and water vapour permeable to allow moisture to escape. 

Concrete Surface Profile We assess the existing or specified concrete surface profile to determine if it is suitable for a resin waterproofing and wearing surface, or if it requires additional preparation such as screeding for remedial falls, or patch repairs and levelling for localised damage. 

Deck Contamination If any exposure or spillage of substances like automotive fluids or de-icing salts on the decks has occurred it could affect the adhesion or performance of a new surfacing system, potentially requiring additional pre-cleaning before mechanical surface preparation. 

Concrete Moisture Content Before applying a new resin surfacing system to concrete decks, we ensure that the moisture content is below 4% or use a moisture barrier or vapour permeable system to manage moisture. 

We’ll refer to FeRFA guidelines and standards which provide us with valuable direction in selecting suitable surfacing materials that address durability, colour scheme, environmental impact, and system sustainability. These specifications will align with standards such as EN1504 for crack-bridging and BS EN1504-2 for skid resistance, with guidance from FeRFA on material selection and application techniques. 

Hopefully this has given you a glimpse of the rigour with which we approach the process of selection, specification and application of our resin-based protective car park decking systems. Please get in touch for assistance with your own or your client’s car park decking.