On the agenda is the exterior plaster of the house!
The house is built, and it remains only to decide whether to fulfill first of all the interior decoration, or more important is the exterior plaster of the house. I must say that the final decision is most often affected by the time of year and such factor as the weather conditions( you will not do the finishing of the walls outside in the rain).But, let's suppose that, while there are clear days, it was decided to finish the exterior decoration. What kind of mixture is preferred for plastering walls?
As such, there are few variations of solutions, but this does not mean that there is no difference which one to use. Walls that are periodically moistened due to the damp climate, as well as cornices and other architectural elements, should preferably be covered with cement or cement-lime mortar. Both of them, along with calcareous, are suitable for exterior finishing of concrete and brick walls.
In a dry climate, brick, wooden and gypsum walls can be finished with clay-lime and calc-gypsum mortars. Gypsum plaster for outdoor works is not suitable because it is easily destroyed by dampness.
What is prepared for plastering for external works
To prepare the most primitive plaster, it is enough to recall the recipe of the masonry mortar: cement, sand and water. The difference is only in consistency, if a rather steep solution is needed to fix the brick, then for the walls it is better to dilute the composition with water to the state of sour cream .With a ratio of cement( grade M-400) and sand approximately 1: 4, the ideal exterior finish of the house with plaster is obtained.
Cement-lime mortar is made almost as well, only lime dough is needed instead of water, due to which the composition is extremely viscous. Lime is thinned in a proportion of 2-5 kilograms per half a bucket of water, depending on what consistency a solution is needed. Cement with sand are mixed in a ratio from 1 part to 4 to 1 to 6, after which they are poured with a lime mortar.
The strength, the rate of solidification and the elasticity of plaster solutions can be controlled with the help of plasticizers.
Lime mortar is not only the same dough described above, but also an admixture of a certain amount of sand( in the interval between 2 and 4 parts per 1 part of lime).A small amount of cement( 2 full trowel) will significantly strengthen the composition.
Lime-plaster mortar is made with the addition of gypsum dough and, importantly, portionwise, since it begins to freeze after 6 minutes and ends in half an hour. The plaster of the outer walls is also made with a clay-lime composition, which is identical to the previous one, only one part of the clay dough is used as an additive.
For lime-gypsum plasters, slowing agents such as slaked lime in the form of dough( 0.2-0.5%), aqueous alum solution( 5-20%), aqueous borax solution( 5-20%) can be used.
How plastering of external walls is carried out
The set of actions for external finishing by any of the solutions listed above is pretty standard, although if everything is done according to the rules, the spray, the primer and the covering should differ slightly in the proportions of the components. For example, the plastering of external walls with cement mortar begins with a spray, which according to the recommendations of experts should contain from 1: 2.5 to 1: 4 cement and sand, but the soil is carried out at a ratio of 1: 2 or 1: 3 of the same materials. The covering should generally consist of 1: 1 or 1: 1.5 cement and sand.
But these are all rules of a rather laboratory nature, which are not rigorous at home. In fact, it is quite enough just to slightly change the consistency, to spray the walls with a fairly liquid composition, and apply a thicker primer. The consistency of the finishing coat should be somewhere between the spray and the covering.
Plaster of external walls - order of operations for finishing
First, the liquid consistency of the solution you choose is mixed, a broom or maklovice is dipped into it. After this, taking a stick into the other hand, we start at a short distance from the wall to knock on it with a broom so that the spray flew to the surface being treated. This will be sprayed.
The primer is applied by a trowel, for it we use a thick mortar, like a quality village sour cream, in which there should be a spoon. The trowel is placed at an acute angle to the surface, so that the plaster is damped. This layer, depending on the chosen solution and the unevenness of the walls, can form together with the previous thickness of 1 to 3 centimeters.
Cover - a finishing layer, on a wall that is already sufficiently flat, therefore, after waiting for the drying of the soil, we prepare the solution in the consistency of liquid sour cream and apply a plaster thickness of 1-2 millimeters. Having achieved homogeneity of the surface, we leave the finished wall covering to dry and gain strength.
