Plaster

From ancient times until now, gypsum has been used to cover various surfaces. Gypsum is a mineral substance 

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formed from the evaporation of saline and surface waters millions of years ago, forming sedimentary layers that are abundant. The first step after constructing load-bearing walls is to cover them due to their uniform surface, beauty, impact resistance, etc. With technological advancements and the use of polymer materials in mortar mixes, new compounds with names like soft plaster, rough plaster, and decorative plaster have emerged.

This article examines the strengths and weaknesses of using gypsum, and then presents reasons for replacing it with innovative building materials:

The properties of gypsum include acoustic properties, fire resistance, low cost, easy accessibility, and high paintability, while its disadvantages include high water absorption leading to gypsum crumbling, discoloration, crumbling, lack of adhesion to metal surfaces, etc.

New coatings called plaster have entered the construction market, made from polymer materials, cement, and colored granules. With a very thin layer, plaster can cover any surface. Rough and soft plasters prevent cracking due to their materials and have high abrasion resistance and tensile strength. As mentioned, plaster can be used on all surfaces, but it is better to use mesh when applying it to columns to ensure complete adhesion.

One advantage of plasters is their drying time. Considering that gypsum sets very quickly, it should be applied in small areas, making the process time-consuming. However, plasters have a slower drying rate compared to gypsum, so they can be used over larger areas. Plasters, due to the materials used, such as cement, have twice the adhesion compared to gypsum, which is why they adhere to all surfaces.

Plaster is suitable for the following purposes:

  • Smooth structural thickness from 2 to 5 millimeters in one layer
  • Brick or concrete walls, ceilings
  • Rapid application on stonework
  • Indoor and outdoor use

Practical instructions for decorative plaster:

  • Surfaces must be clean, solid, and free from any dust that may prevent adhesion.
  • Do not add external materials other than water to the mixture.
  • Mix slowly with a mixer until the mixture becomes uniform.
  • If necessary, adjust the consistency of the mixture by adding water again.
  • The amount of water needed is adjusted according to the weather conditions.
  • If the amount of mixture with water is not as specified, it may create differences in the pattern or on the surface.
  • Apply the homogeneous mixture properly with a trowel on the surfaces, and remove excess material from the surface to obtain a layer with the thickness of the particles present in the product.
  • Do not reuse hardened materials by adding water again as it loses its properties.
  • It irritates the skin upon contact.
  • Use work clothes, protective gloves, mask, and goggles.
  • In case of contact with the eyes, rinse immediately and seek medical advice.
  • Clean your equipment before drying after use.

Features and Benefits of Plasters:

  • Low adhesion speed compared to plaster
  • Easy performance
  • Elimination of surface defects
  • Durability
  • Smoothness of rough areas
  • Homogeneous appearance after use
  • Effective in lightweight construction (as it can be applied in a single thin layer instead of multiple layers)
  • Excellent adhesion
  • Suitable performance
  • Stable quality
  • High compressive and tensile strength of mortar due to the thin layer applied
  • The most suitable combination for use on lightweight building blocks
  • Elimination of thermal bridges when using lightweight blocks due to similar material to the block