What are Cold-Applied Roof Coatings and Cements?
Cold-applied coatings and cements are those that are designed to be used at ambient temperatures, requiring little, if any, heating to facilitate application. Typically, they are comprised of a resin, a carrier solvent, reinforcing fillers, and optional reflective pigments. Upon application, the carrier solvent evaporates from the coating, leaving a cured, water resistant film.
Roof coatings and cements are available with a wide range of properties and consistencies to fit a multitude of purposes. Low viscosity, non-fibered coatings are formulated as penetrating primers and damp proofing coatings. Medium viscosity, fibered and non-fibered coatings and cements are formulated as interply adhesives and top coatings for use on commercial, industrial, and residential roofs. Some of these coatings incorporate pigments (aluminum, titanium dioxide and others) to reflect the damaging rays of the sun, creating a longer performing and more energy-efficient roof. High viscosity, heavy bodied cements are designed for adhering waterproofing membranes and components, and for patching and repairing leaks.
The primary advantages of roof coatings and cements are their economical, proven performance life, and ease of use. Roof coatings and cements are generally one-component products that can be applied directly from the container. Today’s coating and cements are versatile and applicator friendly. Non-flammable products are also available.
Bituminous Roof Coatings and Cements
Traditional bituminous roof coatings and cements are made from “cutback” bitumen. Distillate bitumen residue is further refined to various specific physical properties through vacuum distillation or oxidization. This refined bitumen is then blended with a petroleum solvent, such as mineral spirits, to make the cutback bitumen. This blend of bituminous resin and solvent is further combined in various type mixing or dispersing vessels with special clay fillers, surfactants, fibers or fillers to create a gelled coating. Reflective aluminum pigments may also be incorporated into the mixture to formulate a coating that provides protection against the damaging effects of the sun’s rays. The proportions of each of these components ultimately determine the consistency and properties of the coating or cement.
Polymeric Roof Coatings and Cements
Coatings and cements can also be formulated with a variety of synthetic resins such as acrylic, neoprene, styrene butadiene, urethane, polyvinyl acetate and others. The enhanced performance properties achieved by using these resins include, but are not limited to: low temperature flexibility, chemical resistance and elasticity. Like bituminous coatings, polymeric coatings can be either solvent or waterborne. In addition, they can also incorporate fibers, fillers, clays and pigments to achieve the desired consistencies and properties.
Polymer Modified Roof Coatings and Cements
These coatings and cements are a hybrid of the previously discussed groups. They are manufactured by combining a portion of the polymeric technology with bitumen technology. The resultant coating or cement exhibits an economical blend of performance properties and characteristics. These coatings and cements are also available in solvent and water borne versions, with a selection of consistencies and properties.
Roof coatings, in all their various forms — bituminous [asphalt or coal-tar] and non-bituminous [acrylic or elastomeric]; brush, spray or trowel grade; petroleum solvent or water thinned; furnished in cans, pails, drums or tank wagons — are all quality products that are easy to use and economical.