Internal Plastering

Definition: Internal plastering refers to the application of plaster on the interior surfaces of walls and ceilings. It provides a smooth and firm finish, acting as a thermal insulator and fire protection layer.

Materials Used: Common materials include cement, sand, and water, often mixed in a ratio of 1:6 (cement to sand) for internal walls. Gypsum plaster and lime plaster are also used for specific applications.

Process: The process involves preparing the surface by cleaning and filling any holes, applying a base coat, and then a finishing coat. The first coat is typically around 12 mm thick, followed by a thinner finishing coat. Proper curing is essential to prevent cracks.

External Plastering

Definition: External plastering is the application of plaster on the outer surfaces of buildings. It protects the structure from weather elements and enhances aesthetic appeal.

Materials Used: Similar to internal plastering, but often a stronger mix is used, such as 1:4 (cement to sand), to withstand external conditions. Waterproofing compounds may also be added for additional protection.

Process: The external plastering process includes surface preparation, applying a base coat (usually thicker than internal plaster), and a finishing coat. The total thickness can be around 20 mm, applied in two layers. Curing is also crucial to ensure durability.

Key Differences

Purpose: Internal plastering focuses on aesthetics and insulation, while external plastering emphasizes protection against environmental factors.

Material Ratios: The mix ratios for external plastering are generally stronger to withstand weather conditions compared to internal plastering.

Application Techniques: External plastering may require additional techniques to ensure adherence and durability against moisture and temperature changes.