September 07, 2022

Why We Need Elastomeric Deck Coatings

For this week’s blog we explain why it is important and necessary to coat your parking garage, pool deck, balcony, pedestrian walkways, etc. with an Elastomeric Deck Coating. In order to understand Why, we must first start at the beginning and explain What a deck coating is.

What are Deck Coatings?

Deck Coatings consist of multiple layers of fluid applied compounds that cure to a tough elastomeric, resilient, waterproofing coating. When properly designed and formulated, these coatings are engineered systems that prevents water from entering the surface to which they are applied while providing a safe (nonslip) surface with pleasing aesthetics.

Engineered Systems will be elastomeric so as to span structural or shrinkage cracks that manifest in the concrete. The Base Coat must adhere tenaciously to the substrate so as to prevent the migration of water in the event of physical damage to the coating. Each component of the system must likewise have excellent adhesion to each other so each component can work as one, yet provide individual properties to enhance the system. The system must have a topcoat with a high tensile strength to withstand the rigors of pedestrian or vehicular traffic.

Why are Deck Coatings Needed?

  1. Deck Coatings protect the surface to which they are applied from the affects of water penetration.
    1. Water penetrates concrete through open pores in the concrete left when the water used in the making of the concrete evaporates.
    2. Water also penetrates concrete through shrinkage or structural cracks in the concrete.
    3. In freeze-thaw areas, the water that enters the concrete freezes as it very slowly passes through. As you know, when water freezes it expands, exerting a lot of pressure from within the concrete. This outward pressure, eventually causes the concrete to break away. A condition known as “spalling”. Spalled concrete allows even more water to enter into the concrete, resulting in more spalling and ultimately total deterioration of the concrete.
    4. Concrete decks contain steel reinforcing bars to give strength to the concrete. Many balconies on high rise building are cantilever. These decks depend entirely on the steel to hold them up. Water enters the concrete via cracks; it causes the re-bars to oxidize (rust). Like frozen water, the oxidation grows and puts a great outward pressure on the concrete, resulting in the concrete breaking (spalling). The steel re-bars which are vitally important to the structural integrity of the concrete deck eventually deteriorates, jeopardizing the very existence of the balcony. In coastal areas where salt is continually present, the airborne chloride ion (salt) is on the deck surfaces and carried into the concrete with rain water. The salt enhances the deterioration process of the steel re-bar. Inland areas are not spared from the effects of salt as in the northern climates; salt is used on the roads to remove ice. This road salt is carried into parking garages along with accumulated ice. As the ice melts, it carries the salt into the cracks in the concrete.


  1. Deck Coatings protect the area below the surface to which it is applied from the affects of water penetration.
    1. Occupied space beneath a plaza deck, walkway, balcony, recreation deck, terrace, and other areas subject to walking (pedestrian) traffic.
      1. Water entering these areas from the deck above will cause unsightly and perhaps very costly damage. (ie: Stained ceilings, damage to furniture, carpets, paintings, etc. Water in electrical fixtures can cause loss of power or fire.) In walkways, there is generally a plaster ceiling below, which will fall down in large pieces as the water penetrates the concrete.
    2. On decks subject to vehicular traffic, there is usually parking decks below the top parking deck.
      1. Water penetrating a parking deck with automobiles parked below will seriously damage the paint finish. (ie: As the water goes through the concrete it collect efflorescence from within the concrete. This is a lime product and it damages the paint finish.)
      2. Quite often, there are retail stores or storage areas under a parking deck. In these areas, the parking deck is actually the roof of the stores or storage areas. As a roof, it must be waterproof and still have the ability to drive cars over it. A tough, elastomeric, water-proofing deck coating is the answer.


Where Pecora Deck Coating Systems are applied on structures?

    1. Parking decks and garages
    2. Roof Top Helipads
    3. Ramps, loading docks or emergency entrances
    4. Mechanical equipment rooms (either interior or exterior)
    5. Walking decks
    6. Balconies
    7. Rooftop recreational areas
    8. Sun decks
    9. Elevated Tennis or Pool Decks
    10. “Eyebrows” which receive foot traffic
    11. Elevated Pedestrian walkways
    1. Under tile (ceramic, thin set or quarry tile)
    2. Below-grade
    3. Planter boxes
    4. Split slab construction
    5. Plazas
    1. Roofing which will have window-washing equipment or considerable maintenance traffic
    2. Roofing or re-roofing over structural concrete
    3. “Eyebrows” that do not receive foot traffic
    4. Other


Type of structures where Pecora Deck Coating Systems are commonly specified:

  1. Parking structures
  2. High-rise office building
  3. Sports stadiums
  4. Hotels
  5. Hospitals
  6. Wastewater and sewage treatment facilities
  7. Department stores
  8. Shopping centers
  9. Multi-Story Manufacturing facilities
  10. Multi-Story Distribution centers
  11. Detention facilities
  12. Multi-Story Condominiums
  13. Convention center
  14. Apartment Buildings
  15. Schools & Universities


For more information or deck coating application and equipment recommendations, we urge you to contact our Pecora Corporation Technical Services Group. Our expert team is highly qualified to answer any question, recommend the proper solution, or provide testing training. Our Technical Services staff offers training in product technology and use and provides the technical assistance you require in the planning and implementation of your project. They can be reached by email or by phone (800)-523-6688.


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