Where is the lime plaster used?
Plaster solutions based on lime can be safely attributed to universal materials. Lime plaster trim both the facades of houses, and living quarters. This is not an accident: limestone plaster is available, reliable and undemanding to the material from which the wall is built - unless it is afraid of moisture and therefore not suitable for bathrooms and various cellars, but its popularity is practically not affected. However, in the bathroom you can use a mixture of lime with cement - so-called.a complex solution that sets much faster and safely tolerates the effects of both moisture and temperature.
Based on lime, simple plasters are created for subsequent painting, as well as decorative for finishing facades. The main difference between them is the choice of the component with which the lime will be mixed. What can I choose to prepare a lime solution?
- Gypsum. Lime-plaster solution very quickly seizes, literally for 10 minutes, so it is prepared in small portions and immediately put into operation. Lime-plaster plaster is used for finishing cornices, wooden and stone surfaces.
- Cement. As already mentioned, when mixing lime with cement, is obtained with , a complex solution suitable for humid rooms - a bathroom, a cellar or just a distant room in an old-old house, where sunlight does not penetrate for years. Since cement is an expensive treat, the lime-cement mortar is practically not used in the decoration of new premises: it is a method of exclusively repair work.
- Sand. Lime-sand plaster - the most common mixture, for its preparation is suitable for almost any sand. But it is worth remembering that, depending on the type of sand, it must be properly prepared: rinse with water if it is brought from the river or the sea, or sift, if the sand is extracted far from the reservoirs.
- Clay. The use of clay as a filler is not as common as the use of sand or gypsum. Lime-clay mortar is used to fix a layer of pure clay mortar, which is not particularly strong.
After the wizard determines the additional component, the preparation time of the solution comes. In this process, there are some subtleties that you should know, so that ten times you can not alter the same wall ten times.
How to prepare a mortar for plaster?
It would seem that in the preparation of the solution there is nothing difficult - take it and mix lime with anything! But if everything was so simple, this article would not have arisen. Plastering of walls with a calcareous mortar requires considerable experience - the work has to take into account a number of points about which the beginning plasterer may not even suspect.
In what proportions should you use the components? For each filler, the figure is different: the calc-sand solution is prepared in the proportion 1: 4( 1 part of lime, 4 parts of sand), lime-cement - about 2: 1, calc-plaster - 3: 1, etc.
What viscosity should the solution have? To define it is not difficult: we take a shovel which we use for mixing, and we try to separate it from a solution. If the solution drains easily - the viscosity is insufficient, you need to add more plasticizer. If, on the contrary, the scapula hardly resists dense mass - that means, bust, it is necessary to breed more senile. Ideal is the option, when the solution lies a thin layer on the shoulder blade - this means that it will hold well on the wall.
How quickly will the mixture cool down? It all depends on the choice of placeholder. The calcareous-gypsum solution freezes almost instantly, literally in 10-15 minutes, and cement-lime mortar can dry and seize for 2-3 days. To accelerate the solidification of the latter, PVA glue is often added.
It should be remembered that the lime is damp and unshakable .The composition of the lime plaster includes slaked lime, which is pre-prepared for many weeks. However, even this period does not always guarantee the quality of the solution: the unused pieces that have fallen into it can swell and lead to cracks after the end of the work. Therefore, often use strongly crushed quickly quenching lime, which is prepared for half an hour.
What should I remember when working with lime plaster?
- Lime is a fragile material. Before using the plastered surface, it is necessary to give it properly to freeze.
- It is better to add water to the solution not with a jet, but with a sprinkler - for example, a garden watering can: so less binding material is washed out.
- Before plastering the surface must be cleaned to the state "exactly as in the desert", otherwise the repair of the lime plaster will fly into a pretty penny.
- When quenching, lime increases in volume, so a suitable container should be used.
- For long-term storage, lime plasters lose their viscosity, and after a few days of waiting, you need to add astringent material to the solution.
- The easiest way to determine the degree of readiness plastered with a lime mortar wall is to notice how much it has turned white.
If you correctly use all these tricks, you can significantly reduce the cost of repairs and improve the quality of wall finishing at times!