What is Roughcasting?

Roughcasting is a type of exterior finish, in which pebbles and stones are mixed into the concrete or plaster as a finish for the exterior surface of the walls. The material dries into a rough, durable finish that is often maintenance-free for decades. Roughcasting is often confused with pebbledashing, a process where pebbles and stones are thrown against a soft cement finish.

Roughcasting is a type of finish for commercial and residential buildings that uses gravel to create a smooth surface. The practice, which originated in Great Britain, was once common on outbuildings but has become more popular in home construction. Remember, that only proven companies will do this job well.

In some areas of the world, roughcasting includes the use of tiny sea shells instead of sand or gravel. Tinting and color additives are also used in sand or gravel mixes to add a certain color to the finished home. While primarily used for exterior wall finishing, roughcasting is also a unique way of adding flavor to an interior wall.

A modified version of roughcasting is used to waterproof basement walls in some areas. A plastic sheet is fastened against one wall, and a plaster and chemical mixture is sprayed over the plastic. The surface dries to form a waterproof barrier. This type of waterproofing is often applied in the construction of tunnels; however, it is an expensive means to a problem that is often better dealt with using much more common methods.

One drawback to roughcast finishing is that it is difficult to match the repair color and finish textures. On areas which become damaged, new roughcast is often easily detected among the original finish. Weather and time factors can make it difficult to replicate the original batch when mixing a new batch of wall covering. It often becomes necessary to remove the original finish and recover an entire wall.