Finishing work. PRODUCTION OF PLASTER WORKS.7. Requirements to the quality of plaster. Major defects

High-quality plaster should not have cracks, tubercles, shells, dutikov, rough rough surface. Plaster surfaces are checked using a rule or a template, and for curved surfaces, using patterns.

Dutiki - small bumps on the surface of the plaster. They fall off easily, leaving a white or yellowish stain. Dutik form from the use of lime mortar, in which small particles are not extinguished. Such quenching can last a long time; dutik clean off, on this place again put plaster solution.

Cracks can appear on the plaster from the use of fat, poorly mixed solutions, from the rapid drying of the plaster, applying at once thick layers of bent-up and even thin-layer mortars onto the previous layer that has not yet seized. To eliminate cracks, it is necessary to apply well-mixed solutions. Plaster must be protected from extremely rapid drying, in dry and hot weather it must be covered or often watered.

Pitting and bloating of plaster can occur from plastering of wet surfaces or constant wetting of plastered surfaces. This is typical of lime and lime-gypsum plasters. The defect is corrected by removing a poor quality area, drying the base and applying cement mortar to the surface, mortar with the addition of liquid glass.

Peeling of plaster can occur with a dry base. Delamination may be the result of applying a lime mortar on a concrete base or a more durable mortar on a less durable layer, which as a result lags behind the base.