Low-VOC Polyurethane Deck Coating

by

Steve A. Parker

Low-VOC polyurethane-based formulations are some of the most important products to have come out of manufacturers’ labs to satisfy the requirements for deck coatings of commercial and industrial facilities. These new line of deck coatings are very flexible in any type of weather conditions and boast of more functional and decorative features that help repair, protect and enhance all types of decks.

Polyurethane deck coatings maintain deck quality as liquid-applied single-components coatings. These polyurethane deck coatings come in concrete, gray, or tan colors and are moisture-cured and slip-resistant, characteristics that are very suitable for waterproofing trafficked or pedestrian areas like parking decks and roof decks.

Low-VOC deck coatings are also suitable for exterior and interior applications and retain their elastomeric properties in extreme temperatures such as freezing weather or very hot climates.

Applying Low-VOC Polyurethane Deck Coating

Low-VOC polyurethane deck coatings can be applied in any types of decks. For lightly-trafficked surfaces such as patios, roof decks and sun decks, low-VOC deck coatings can be applied to a primed concrete surface using one liter of paint to around 1.57 square meter of deck area. This will result to .63 centimeters of thickened film. To avoid pinholes, extra care should be taken when applying the deck coatings, applying the formulation as uniformly as possible. If pinholes are unavoidable, immediate repair should be done on the surface.

A low-VOC glaze is then roller-applied, although brush or spray painting can also be used to achieve a 0.4 millimeter film thickness. A gallon of sand is immediately broadcasted uniformly into the wet surface, with backrolling done on the surface to evenly distribute the deck coatings. Generally, it takes only an overnight curing process before the deck surface can be used for pedestrian traffic once again.

In the case of medium- to heavily-trafficked deck areas, the initial coating application of low-VOC deck coatings is allowed to cure overnight. Another layer of deck coatings is applied the following day and sand is broadcasted to the surface. The coating and sanding process is repeated in as many days as recommended by manufacturers, until a final top coat is applied and allowed to cure for 3 days to complete the deck coatings system.

Low-VOC Polyurethane Deck Coating Materials

For a complete and correct application of the deck coatings system, there are several materials used in the process. The main material is the low-VOC polyurethane coating whose main use is to waterproof the deck membrane with its elastomeric properties, usually a one-part and self-leveling formulation that also interacts with the sand aggregate. Another material is the two-component and solvent-based epoxy primer that prepares concrete and metal deck surfaces prior to coating application.

A single-component and non-staining polyurethane sealant is another material used in deck coatings systems. When cured at the right temperature, it becomes rubber-like, which is flexible and tear-resistant. To increase slip- and wear-resistance, sand aggregates are used at every coating layer. To complete the deck coatings system, a polyurethane top coat is needed to protect the deck coatings from ultra-violet exposure.

Article Source:

Low-VOC Polyurethane Deck Coating

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