4 important questions about plastering internal walls

4 important questions about plastering internal walls

Internal walls can be plastered all year round, even in winter. All you need to do is remember a few rules to avoid unpleasant surprises in the form of cracked or peeling plasters or discoloration. The final shape, color and appearance of internal walls and ceilings depend primarily on the plastering work. It is an important and integral element of construction works, both during the construction and general renovation of a house or flat.

When can you plaster?

We can start work after the period of settling and shrinkage of the walls, ie optimally from 3 to 6 months after completion of work on the unfinished state. At this time, the building should initially settle. Concrete and concrete substrates require waiting for at least 2 months. Also note that plastering of the walls requires certain atmospheric conditions: should not be plastered at a temperature lower than 5 ° C and above 25 ° C. A lower temperature would lead to the freezing of the plaster, which in turn, leads to its uneven drying out and discoloration. On the other hand, work on dry and sun-warmed walls should be avoided during the summer.

How to prepare the substrate?

Proper preparation of the substrate is an important element of plastering work. The ideal wall should be even, dry

and not dusty. It is also important that it is rough and evenly absorbs water and that the substrate is free of efflorescence and free of scratches and cracks. All unevenness and dirt should be removed before starting work - only such conditions will guarantee us optimal plastering results. Remember to cover and attach, for example with a steel mesh, all metal and wooden elements. Metal elements must be additionally protected with anti-corrosive agents. What is important, in the case when the substrate under the plaster is extremely absorbent, such as cellular concrete or silicate blocks, it is recommended to make (for a well moistened wall surface) mortar made of, for example, cement Lepo Lafarge and sand in the proportions 1: 1. Such a treatment will significantly reduce its absorption.

What to remember when preparing the mortar?

The basis of plastering mortar is the appropriate selection of the proportions of individual components, so that it obtains the right consistency. For the mortar to meet all requirements, always use good quality ingredients. When you earn it, remember to mix the right order - cement, sand and 2/3 of the water are mixed first. Then slowly add the rest of the water until the required consistency. It should be remembered that the ready mortar maintains its properties for about 3 hours. After this time, it should be unconditionally discarded. It is also unacceptable to add water for reuse. This threatens the insufficient strength of the plaster, and thus its damage, cracking and falling away.

How to plaster?

The key element is proper preparation of the plaster mix. It must be chosen in complete agreement with the design and technical specification. The recommendations placed on the cement packaging must also be taken into account. It should be remembered that the plaster profiles must be selected in accordance with their future function and that no empty space can be allowed behind them. In addition, plastering netting must be applied to all areas exposed to cracks in accordance with the technical specification. The thickness of the finished plaster depends on many factors: the substrate, the mix itself, the way it is made, as well as the number of layers.

We can distinguish the subsequent stages of laying various types of plasters:

- making the casting of a rare mortar with a thickness of 3 - 4 mm . The consistency of the coating should correspond to a 10 -12 cm draft of the measuring cone;

- after a slight curing of the coating, a coating of 8 - 15 mm is made . The mortar density should not exceed 9 cm immersion of the measuring cone;

- the next layer is made of thin mortar with fine sand with a grain size below 0.25 - 0.5 mm . The mortar should be more "oily" than the topping, while the thickness of the coat is usually 1 - 3 mm . After concentrating the finishing coat, it is rubbed with a wooden, steel or felt-covered wooden packet, depending on the type of plaster finish.

Cement recommended for plastering mortars

Lepo is a masonry cement that does not require the addition of lime or plasticizers. It was developed for mortar masonry and plastering, it is also perfect for finishing works, for example leveling the floor under the floor, or other minor renovations. It is characterized by good adhesion to the substrate and high workability, thanks to which it accelerates the pace of construction, reduces executive costs and material losses arising during masonry and plastering works.