Liquid roofing

Liquid Roofing is the process of waterproofing a roof by the application of a specialist liquid roof coating. It is suited to all types of roof, including flat, pitched, and domed.

The concept of liquid roofing has existed since (at least) the early 1800s, when natural bitumen was combined with jute, straw, rag felt and other man made materials to provide a waterproofing solution for roofs. In the early twentieth century the manufacture of liquid roof coatings became a commercial activity, with the earliest coatings being based on liquefied rubber. The 1960s and 1970s saw the introduction of acrylics, acrylic emulsions, styrene butadienes and unsaturated polyesters, which led to improved quality and durability of the coatings. In 1975, the first water based elastomeric roof coatings were introduced. In the late 1980s, single component moisture-cured polyurethane coatings were developed and remain the basis of the majority of today's cold liquid applied roof coating technologies.

Liquid roofing involves the application of a monolithic, fully bonded, liquid based coating to a roof. The coating cures to form a rubber-like elastomeric waterproof membrane, capable of stretching and returning to its original shape without damage. Such coating systems are usually reinforced with secondary materials such as glass-reinforced plastic to provide additional tensile strength. The coatings can be applied over most traditional roofing materials, including felt, asphalt, bitumen, and concrete.

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