plastering using cement

Cement plastering is an ideal plaster for exterior rendering. It is particularly suitable for damp conditions such as bathrooms, cisterns, water tanks, floors, copings, etc. where non-absorbent surfaces are desired. Cement plaster is usually applied in one coat. However, in some cases when the thickness of the plaster is more than 15 mm or the finish is better, the plaster is applied in two layers.

First coat or rough coat: Generally, the average thickness of the first coat of plaster is 12 mm on brick masonry or ashlar masonry and 23 mm on rubble masonry. In case of concrete masonry, this thickness varies from 9 to 15 mm depending on the nature of the work. For the first coat, cement plaster with a mix ratio of 1:3 or 4 (1 cement: 3 or 4 sand) is usually used. The first coat of plaster is placed on the surface of the wall between the spaces or bays formed by the screeds. This plaster is applied with a mason’s trowel. The surface is then smoothed using flat wooden floats and straight edges of wood and finally finished by polishing with a trowel. If a second coat or thin coat is to be applied, the surface of the first coat is not polished, but roughened with an abrasive tool to form a key for the second coat of plaster.