grouts

Grout is a dense, cementitious paste used to fill and seal the joints between tiles or masonry units. It provides a finished appearance, helps distribute loads, and prevents water, debris, and pests from penetrating substrate. Grout differs from mortar, which binds structural masonry, and from plaster, which coats walls. The choice of grout affects durability, hygiene, and aesthetics in tiled surfaces and brickwork.

There are several grout types. Cementitious grouts are common, made from cement, aggregates and water or polymers. They come in unsanded grades for narrow joints and sanded grades for wider joints; polymer-modified variants improve flexibility and water resistance. Epoxy grout uses epoxy resins and hardeners, offering high stain and chemical resistance but requiring careful mixing and longer curing. Ready-to-use formulations are also available.

Key properties include strength, water absorption, shrinkage, and color stability. Cementitious grouts must cure with moisture and are prone to efflorescence and staining if not sealed or properly cared for. Epoxy grouts resist staining more effectively and do not require sealing, but are harder to install and costlier. Sealing is commonly recommended for cementitious grouts to improve stain resistance and cleanability.

Applications include interior and exterior tile installations in kitchens, bathrooms and floors, as well as masonry joints in walls. Installation typically involves surface preparation, mixing, filling joints with a rubber float, cleaning haze, curing, and sealing where appropriate. Maintenance includes regular cleaning and periodic resealing of cementitious grouts. Common problems are cracking, efflorescence, discoloration, and mold, often caused by movement, moisture, or inadequate sealing.