Material used for making watertight repairs outdoors and in bathrooms and kitchens. Sealants are flexible materials that are able to adhere to the adjacent surfaces and still expand and contract with structural movements.

Soft mastics are the most commonly used sealants. They are applied with a trowel, mastic gun or straight from the tube. Sealing tape is generally used on surfaces that have a hole or leak – for example, when temporarily sealing a lean-to roof.

Sealer: Coat of paint or other material applied to a surface to seal it in preparation for finishing. Special sealers are available for different surfaces, such as wood and floors.