Plastering and rendering are both the process of covering walls. The main difference in the two practices is that plastering refers to coating the interior walls, whilst rendering is the coating of exterior walls. The major distinction between plastering and rendering is the strength of the materials used in each. Nonetheless plaster and render are both made from the same building materials including, cement, sand, water and lime gypsum.
Rendering is used to coat exterior surfaces of buildings, and contains a higher percentage of cement within its composition. Rendering is applied to the outside of buildings to not only make the outside facade more visually appealing, but also provides waterproofing and fireproofing efficiencies.
Rendering is made up of a composition of lime gypsum, sand and cement, bonding agents, drying additives and colouring. Lime gypsum is key to giving the coating its creamy appearance and smooth finish. Finer sand must be used in the rendering mixture to create the coveted finish.
Render is layered onto exterior walls in sheets, applied with a trowel and finished with a number of different tools, dependent upon the desired finished appearance. Rendering can either have a smooth, flat finish or a textured, patterned appearance, determined by the homeowners personal taste.