Plaster
Definition
General concept of plaster
Plaster is a layer of mortar or mixture applied to surfaces, mainly walls, in order to protect, waterproof, level and beautify said structures. It is used in both new constructions and restorations, being essential to improve the durability and aesthetic appearance of constructions.
This construction technique acts as a protective barrier against external agents such as humidity, wind or mechanical impacts, in addition to allowing a uniform finish prepared for subsequent treatments or painting. Depending on its components and application methods, plaster can offer specific properties, adapting to the particular needs of each work.
Materials and composition of the plaster
Basic components of the mixture
Plaster is mainly composed of a mixture of cements, lime, sand and water. The proportion and quality of these materials vary depending on the type of plaster desired and the specific use that will be given to it. The sand must be clean, with adequate granulometry to avoid cracks, and the cement and lime act as binders that provide resistance and adhesion.
Water is incorporated to facilitate mixing and application, but its quantity must be carefully controlled to avoid a mixture that is too liquid and could lose cohesion. In some cases, additives or plasticizers are added to improve the workability and durability of the plaster.
Variants according to materials
There are different types of plasters depending on the materials used. Lime plaster is traditional and offers good breathability and flexibility, ideal for old buildings and humid areas. Cement plaster is more resistant and rigid, used for exteriors and structures exposed to mechanical or climatic attacks.
Single-layer plasters are also used, which include additives and pigments for decorative finishes, and plasters with special fillers such as fibers or polymers that improve impact resistance and impermeability. The choice of material greatly determines the behavior and useful life of the plaster.