The composition of cement- sand plaster , instructions for application and consumption

Modern building materials market is literally saturated with different products.Plaster compositions are also presented in a large range, but still the preference is often given to mixtures based on traditional ingredients - sand and cement.Perhaps, partly because they have long passed the test of time.

Before considering all the properties of the cement-sand plaster, it is appropriate to answer the question, why do we need such materials?Then features will become more apparent by the DSP solutions.

What gives plastering

• Hides all visible surface defects and ultimately it aligns to "finish" finishes.
• plaster layer structure serves as a solid enough basis for any cladding material.
• can significantly save on materials (and the timing), confining only staining the surface.
• Limits the absorption of moisture in the base material.
• partially performs the function of noise and heat insulation.

The mixture

It largely depends on the purpose for which the plaster is used.In practice guided by the following rules:

binder (cement)

• M100 - 200 for in-house work.
• M250 and more - for outdoor.

Sand

• Preferred river or quarry (sifted), with lows of impurities, particularly clay.
• Grain size - medium.The presence of large lead to surface roughness, and this sand is used for solutions that produce "rough" finish.Fine granules will facilitate the formation of "cobwebs" (cracking) and are used only for solutions that fit the last layer, to obtain a "mirror" basis (usually "under" painting).

In some cases, solution-prepare various additives are introduced which give the final product (or enhance) certain desired properties.For example, reduction of moisture absorption rate, low temperature resistance, flexibility and a number of other - of plasticizers here.

Types of cement sand plaster

feasibility of using this or that technique is determined by the operation convenience, the structure of the specificity (the room), and a number of other factors.

Simple

is used where quality of finish is not determinative.As a general rule:

• to pre-prepare the ground (for example, sealing cracks and other defects);
• before installing the reinforcing mesh for the application of decorative plaster;
• in order antibacterial surface treatment before facing (in the mix appropriate antifungal additives are introduced).

Technique styling - "scratch coat" base in 2 or 3 stages followed by the ground.

Universal

most used technology.Used:

• for surface finishing inside and outside;
• in some cases - for leveling screeds, blind areas, and so on;
• when necessary to improve the waterproofing of "objects" (eg, buried tanks - septic tanks, wells of w / w rings and other).

Technique styling - it has done in 3 stages:

• pre-layer ( "rough");
• soil;
• «skim» (aligned with special devices - float, trowel).

High quality

technology is more labor-intensive and often is used in damp conditions.

Features laying

Operation is not much different from the previous one.Primer is applied in several layers (2 to 4), and "finish coat" certainly "Iron".This increases the strength of the layer and its quality waterproofing.Almost always, especially in large areas, put "beacons".

Equity ratio

largely depends on the requirements that apply to the plaster layer.Most often taken ratio of 1: 3 or 1: 4 (cement / sand).But this average (purely indicative) ratio.Much depends on the quality of raw materials, the specifics of the application of the mixture and a number of points.But in everyday terms can be guided by these values.

algorithm works (general procedure)

Substrate preparation

After her "cleaning" should be primed (eg, "Betonkontaktom").This will prevent the absorption of water from the surface of the material solution.

«obryzga»

Methodology different and is selected depending on experience and technical capabilities.Accordingly, the solution must be sufficiently fluid (medium consistency).

Methods of application:

• with a trowel, scoop or something else;
• hand;
• cleaner using the old model (on a spray gun, a hose connection port from which air is blown).

thickness of the layer depending on the base material (in «mm»):

• timber - 1;
• w / w - about 4.5;
• brick - to 7.

Focusing on these figures, we can determine the approximate flow rate of the solution and, consequently, and building materials.

applying the primer layer

solution is somewhat thicker for him.The first "pass" on the surface is uneven, and this is understandable.He left half an hour to a little "grabbed".Thereafter, all visible unevenness are filled with a solution and then the surface is leveled rule.Perhaps it will have to do several of these approaches.It all depends on the experience of the master.

«nakryvki»

solution DSP preparing enough liquid again.Layer - not more than 3 - 4 mm.Operation shown in Fig.

Feature "Mayak" works

The idea is that each "cell" is filled with a cement-sand mixture, and then it is "smoothed out" by means of regulations.Reiki lighthouses serve as guides for him, to which it is pressed.The collected excess solution filled the void.

After completing this step to begin laying the "finish coat."

plaster layer processing

The fact that such events are held, and in relation to the base, is well known.Coating (impregnation) is carried out with different compositions for the prevention of surface material from the appearance of mold and mildew.When processing plaster task is the same - to protect the hardened mixture from the harmful effects of moisture and thus extend the life of this layer.

This work is called "pickling".For this purpose, typically applied finished products, which are commercially available and are inexpensive.Depending on their consistency, they are applied by spraying or brushing a layer (rubbing) using a roller or brush.

order of use and recommendations for removal of surplus funds are reflected in the instructions to the drug.What

consider

plaster should not be applied once a thick layer.This will cause an uneven drying of its full thickness and hence heterogeneity throughout the volume structure.As a result - the appearance of cracks on the surface and reducing the strength of the coating.

necessary to monitor the quality of the preparation of the mixture.

Firstly , it should not be more or less large particles, otherwise there is the risk of air pockets, and this is also reflected in the strength.

Second , high-quality mixing of ingredients necessary to ensure that the weight of the structure of the DSP was the same throughout.The best way to "mix" - using mechanical means.For example, the cost of a simple construction of the mixer is in the range of 180 - 200 rubles.Corresponding to the punch tip can be made independently, e.g., made of wire of sufficient thickness.

The quality plaster and affect the external environment.A decrease in temperature slows down the evaporation process, and helps draft uneven drying mass.As a result, the upper portion of the bed is covered with hardened crust that literally "block" the moisture out.Therefore, the entire depth of the plaster strength will vary.

Useful tips

• If plaster composition is prepared in the home, from the individual components, as a plasticizer can be used PVA (per 1 liter of solution 6 - 10 ml glue).
• When finishing smooth surfaces (for example, w / w plates) to improve adhesion to a solution for the "scratch coat" it is advisable to add a little tile adhesive.
• quality plaster depends on the date of manufacture of cement.If he had kept more than six months, the proportion of binder in the mixture should be somewhat increased.All the recommended proportions are based on the fact that cement is a relatively "fresh".For reference - the first 8 months he could lose up to 25 - 30% of its qualities (depending on storage conditions).
• before finishing a surface necessary to examine all the information on the maximum and for the preparation of the composition, and characteristics of its stacking is applied to this kind of work.