The final coat of plaster is made of?

The final coat of plaster, often referred to as the finish coat, is typically made of neat plaster. Neat plaster is a mixture of gypsum and water, producing a smooth and durable surface that is ideal for the final application on walls and ceilings. This type of plaster is specifically designed to create a fine finish that can be sanded and polished if necessary, providing an aesthetically pleasing surface that can be painted or left as is.

Other materials like sand, ready-mix plaster, and wood-fiber plaster have distinct properties and uses in the plastering process. For instance, sand is often mixed with plaster in earlier coats to provide strength but is not used in the final coat for a smooth finish. Ready-mix plaster can be convenient for certain applications, but it may contain additives that are not conducive to achieving the desired fine finish. Wood-fiber plaster is used for specific applications such as soundproofing or thermal insulation rather than as a typical finish coat. Thus, neat plaster is the appropriate choice for the final coat due to its compatibility and finishing characteristics.