Efflorescence on brickwork. How to remove efflorescence on a brick with your own hands Efflorescence on a brick causes

Surely everyone at least once saw white spots and streaks on brick walls, which eventually form on almost every building. It also happens that the house is still under construction, and white spots are already showing through. What is it and why does it take place?

What is efflorescence on a brick

Efflorescence on a brick is the result of a natural "deposition" of water-soluble salts that are contained in brick and mortar, formed during the evaporation of moisture from the masonry.

As a rule, the most pronounced white spots on the walls facing the shady side yard, as well as in conditions of high humidity. In addition, efflorescence can form due to a violation of the brickwork technology, improper waterproofing and poor-quality manufacturing of the brick itself, cement and other components.

In addition to the loss of the aesthetics of the structure, efflorescence on the brick can bring physical losses, that is, gradually "eat" the masonry. Therefore, these white spots cannot be left without attention.

Ways to get rid of efflorescence on a brick

You can learn how to remove efflorescence on a brick on your own right now. This task is not difficult and feasible with the participation of a minimum number of tools and means. And yes, it doesn't take much time.

In order to remove efflorescence you will need:

• Washing of efflorescence (ready-made industrial solution or prepared independently).
• Brush with hard bristles.
• Water under pressure (watering hose or high pressure washer).
• Gloves and mask.

Means for removing efflorescence are concentrates or ready-made solutions based on acids (hydrochloric, phosphoric or others). The market offers many options - from domestic to imported washes of different price categories. When choosing a ready-made product, please note that not everyone, including universal ones, is suitable for salts on the wall of your house. Therefore, you should carefully read the annotation for the product and it is advisable to test the product on a small section of the wall.

Using a ready-made wash, it is enough to follow the instructions indicated on the product canister. It is especially important to maintain the recommended exposure time of the drug.

The second option is to make a wash with your own hands. For this you will need hydrochloric acid 2-4% or mixture detergent with vinegar in equal proportions.

Whichever wash option you choose, be sure to work with gloves and a mask, as the products contain acid, the vapors of which can damage the skin and break tooth enamel up to caries.

What you need to do to remove efflorescence on a brick:

1. Thoroughly wash the wall with high-pressure salts.
2. Dry the masonry surface completely.
3. Using a hard brush, apply the solution to the entire surface of the wall and leave to act for the time specified in the instructions for washing (30-60 minutes are enough for a “home” efflorescence remover).
4. After the time has elapsed, thoroughly rinse the solution from the wall and dry completely.

After completing all the steps, it is imperative to cover the masonry with a layer of water repellent. This will protect the wall from moisture penetration and stop the process of salt release. In addition, a wall coated with a water repellent will always look cleaner, as dust will be easily washed away by rain.

Such a picture, which we see in the presented photo, is by no means uncommon. Chaotically located white spots that spoil the exterior brick house, decorated with complex architectural elements, nullify all the efforts of high-class masons.

This plaque is nothing more than salt that has come to the surface, and therefore is called "efflorescence". What are the reasons for their appearance, and how to get rid of efflorescence on a brick? You will find the answer to these questions by reading our material - including the video in this article.

How to prevent the formation of plaque

In any water, even spring water, salts are dissolved - it's just that their concentration is different. Since salt is heavier than water, it precipitates, and when the moisture evaporates, it remains on the surface. It is easy to guess that salt gets into any material, including brickwork, along with moisture.

As a result, such unsightly efflorescences are formed on the brick. How to remove the fight - and even better, how to prevent their occurrence at all? This is the topic we will discuss in detail in this article.

Measures to protect masonry

Such a problem as protecting bricks from efflorescence is relevant only for masonry made of ceramic stones. And the point here is not only that on the red-brown surface, salt deposits are visible, as if in the palm of your hand. Salt also enters into a chemical reaction with the particles of the base, and thereby contributes to its gradual destruction.

• The density of a full-bodied clay brick is approximately the same as that of a silicate brick, and is about 1800 kg / m3. A similar indicator for hyper-pressed brick is 2200-2400 kg/m3. And what is surprising, given that this brick is made by semi-dry pressing. Naturally, it has fewer pores, and it practically does not absorb water.
• On the silicate brick efflorescence also appears, they are simply not visible against the background of a similar base color. Therefore, the question: "How to remove efflorescence on a brick" is asked mainly by those whose house walls are lined with clay bricks or ceramic blocks. We would like to emphasize that it is necessary to start taking care of these materials immediately after they are unloaded at the construction site.

Note! Pallets with bricks should not stand in the open, not covered with anything. Because, having stood in a long rain, having been heavily saturated with moisture and dried, the bricks can become covered with a light white coating even before the wall is laid out of them. Of course, in the process of building a building, they will have to get wet more than once - that's why the builders try to bring the structures under the roof as quickly as possible.

So:

• The problem is that brick walls are built for a long time, they somehow have to get wet in the rain. Therefore, it often happens that salt deposits appear even before the turn reaches the roof. If this happened, then before proceeding with plastering, the brick is cleaned of efflorescence.
• How this is done, we will describe in detail in the next chapter, but for now we are talking about measures designed to protect the masonry from such an undesirable phenomenon. most main defense for bricklaying is plaster. But what if it is not working, but front masonry, which is not subject to plastering?

In this case, water-repellent impregnation will solve the problem, which will not allow atmospheric moisture to enter the pores of the masonry material. Such impregnations are called water repellents, on which we will draw your attention to begin with.

Hydrophobic impregnations: a panacea for non-plastered walls

Here is a paradox: the negative impact, moisture has a greater effect on the most durable structural materials: some types natural stone, concrete and brick. Despite the excellent mechanical strength, the water absorption coefficient of clay bricks can reach 12% by weight, and silicate - even more, up to 18%.

Removing efflorescence on a brick is not the only problem that may arise in connection with this. At sub-zero temperatures, moisture turns into ice, the pores of the material burst, therefore cracks appear both in its thickness and on the surface.

Their number increases with repeated cycles of freezing and thawing, which leads to the gradual destruction of structures.

Properties of water-repellent compositions

Hydrophobic impregnation, which has a rather complex chemical composition, was invented specifically to prevent the likelihood of such phenomena. This is a liquid based on silicone and organosilicon compounds, which, when applied to the surface of a structural material, creates a protective film on it.

• As a result, the capillary suction of moisture decreases to zero, and the frost resistance of the processed material increases. In addition, the facade acquires the ability to self-clean - that is, during rain, water does not absorb, but rolls off the walls, and simply washes them.

• Note that in this case, the vapor permeability of the structures is completely preserved. The film that forms on the surface is invisible to the eye and imperceptible to the touch - but only gives it a characteristic sheen. It not only does not provoke dust settling, but also repels it. There are no solvents and environmentally hazardous substances among the impregnation components.
• It is desirable to carry out processing only on dry masonry - so the water repellent can penetrate deeper. You can, of course, treat a damp surface, but this is done only in situations where it is impossible to dry it. The porosity of the material, in this case, determines the depth to which the protective liquid can be absorbed - on average it is 10 mm.

Note! There are also deep penetration impregnations, which experts call penetrating. They are absorbed to a depth of up to 40 cm, and can be applied not only on a damp, but also on a wet base. Getting into the thickness of the material, the penetrate binds the moisture present there, turning it into crystals.

• Naturally, in this case, moisture from the outside cannot do the same. Such impregnations are used where the masonry needs to be isolated from constant moisture - for example: basement walls, building basement, or well walls. That is, in fact, they are waterproofing material.
• They can also be used as an additive to plaster or masonry mortar. But such compositions are used only for plastering or finishing. If the brickwork itself is decorative coating, then ordinary silicone impregnation is sufficient.

Note! A water repellent is a means to prevent the appearance of salt deposits. If they did not treat the walls immediately after the walls were erected, and the salt has already appeared, then first they use a product to remove efflorescence on the brick, the surface is also cleaned of mold, dust - and then a water-repellent composition is applied.

• Water repellents can be ready-to-use, or concentrated, diluted with water, as the instructions say - usually in a ratio of 1: 2. The price of such impregnations, if we talk about domestic manufacturers, varies in the range of 950 - 1350 rubles. for a five liter canister. Import options due to the high cost of the currency are much more expensive.

All of them are economical, are applied in one layer, and consume a maximum of 100 ml/m2. Thus, 5l of funds is enough to process 50m2 of walls.

Even if you think these expenses are excessive and unnecessary, consider that without them you will have to spend even more. And so, for the next 10 years, the walls of your house will be protected, and you won’t have to think about how to remove efflorescence from bricks.

Removing salt from masonry

For completeness of information, it should be noted that salt does not always appear on the masonry solely due to the absorption of atmospheric moisture. Additives added to the solution - antifreeze, or accelerating setting, may also be to blame here. Of great importance is the water that was used for mixing, and the quality of the sand, which must be washed.

Capillary absorption of moisture occurs primarily due to the absence of interlayers of rolled waterproofing material between the base of the foundation and the basement wall, between the basement and the wall of the house. Moreover, this material should not be laid dry - it should be glued to bituminous mastic.

Usually it is a whole complex of factors that lead to the same result. People who are engaged in construction with their own hands do not always know about such seemingly trifles, or simply do not attach importance to them. And then they puzzle: “How to remove efflorescence on a brick?”. It is good that there are such means that allow you to deal with this, frankly, unaesthetic phenomenon.

To fight, all means are good

Before discussing the masonry cleaning process, let's figure out how to remove efflorescence on a brick. Do it without special means impossible.

Well, you wash the facade, and salt deposits will appear again and again - and this will continue until you do everything right. Let's see what the retail network offers us for this purpose.

• One of the most popular brands of efflorescence cleaners is Neomid-550. This is a universal option that can be used not only for brick, but also for concrete and stone surfaces.
• The concentrated composition, before removing efflorescence on a brick, is diluted in half with water. If cleaning has to be done at sub-zero temperatures, alcohol can be used instead of water. It is packaged in bottles with a capacity of 1l, 3l and 5l, it costs about 400 rubles. per litre.

• Equally effective and inexpensive is the composition produced under the Good Master brand. It penetrates deeply, dissolves and removes salt from the pores. Perfectly removes even old raids. Packed in canisters of 5 liters and 10 liters, the cost is 450 and 860 rubles. respectively. It does not need dilution, as it is already ready for use. Unlike the previous version, it has an acid in its composition, and removes all types of salts.
• Means "Antivysol Aqua" is generally a universal cleaner. It is effective not only against soluble salts, but also against sulfate and carbonate deposits, therefore it can be used not only to remove efflorescence, but also to clean the facade from traces of masonry mortar.

The drug is also active against fungus and mold, which greatly simplifies the task, eliminating the need to also buy a biocidal agent. With the exception of limestone and marble, they can process any surface.

The cleaner is ready for use, packaged in plastic containers of 5 liters and 10 liters, costs within 300 rubles. per litre.

masonry processing process

There are a lot of products designed to remove salts - we have presented only a small overview. As for the process of applying them, whichever option you choose, the processing is carried out in the same way.

• First, the wall must be prepared by cleaning the exfoliating sections of the masonry from pieces and crumbs of brick, as well as treating with a metal brush those places where there are significant salt deposits. They need to be cleaned so that only whitish spots remain.

Advice! Salts have a different chemical composition, and not every remedy may be effective. In fact, what the manufacturer promises is not always confirmed. We would advise you to first buy a liter bottle of the drug in order to test its effectiveness on a small area of ​​\u200b\u200bthe wall. If you did it, then you can acquire the entire volume necessary for the complete processing of the facade.

• If the salt cleaner works effectively, after a couple of minutes the treated area becomes clean. Apply such compositions as a conventional primer - with a roller or brush. You can also use a spray gun, but then the consumption will be slightly more than that declared by the manufacturer.

After maintaining the prescribed number of minutes after applying the drug, it should be washed with water from a hose with good pressure. Then, the walls must be allowed to dry, and the protective silicone impregnation, which was mentioned above, can be applied.

In connection with the presence of requests from builders regarding the formation of white deposits - "efflorescence" on the surface of brick walls, we inform you about the main reasons for their formation and methods for avoiding their occurrence.

The main causes of efflorescence on the surfaces of brick walls

1. The use of a solution for facing works with a high content of impurities and chemical additives that does not comply with the norms of SNiP 3.03.01-87 p.7.32, 7.51 (it is allowed to use cement-sand mortars on portladcement and pozzolanic cements, with a low alkali content of up to 0.6% and a mortar mobility of 4-6 cm), leads to the formation of efflorescence on the surface of the brickwork, and subsequently can cause defects in the front surface (peeling). Visual confirmation - White color mortar joint of brickwork, salt spreads (Fig. 1).

Rice. 1 - Formation of a white coating on the mortar joints and the surface of the brick

2. Poor quality of reference construction works- the presence of spreads of masonry mortar on the front surface of the walls (Fig. 2), non-compliance with measures for the production of masonry work in winter conditions (SNiP 3.03.01-87 p.7.57-7.61).

Rice. 2 - Masonry mortar spreads

Quality control of work on the construction of stone buildings should be carried out at all stages of construction in accordance with regulations Russian Federation - a contracting organization with the maintenance of as-built documentation, the Technical Customer of the construction and the bodies of the State Construction Supervision. In the work production logs, in addition to the usual records of the scope of work, the outside air temperature, the amount of additive in the solution, and the temperature of the solution are recorded. Documents on the quality of the materials used are also attached to the executive documentation (passports for bricks, mortar, test reports mortar mix accredited specialized laboratory).

3. The thickness of the horizontal seams does not comply with SNiP 3.03.01-87 p.7.6 (norm 12 mm +/- 2 mm) (Fig. 3).

Rice. 3 - Violation of the thickness of the mortar joint

Many builders “blame” brick for the appearance of efflorescence, but this is refuted by tests of bricks for capillary suction (Fig. 4).

Rice. 4 - View of a brick sample before and after tests for capillary suction

The following image (Fig. 5) clearly demonstrates that the reason for the formation of efflorescence lies in the solution. On the front surface of the floor slab, traces of salt migration from the mortar used during construction are clearly visible, which is also not allowed. normative documents on the quality of concrete products.

Rice. 5 - The presence of efflorescence on the floor slabs

The main cause of efflorescence is the content of various salts in the masonry mortar. This is confirmed by the fact that when storing bricks on outdoors precipitation does not change its appearance. The mineralogical composition of efflorescences almost completely corresponds to the alkaline compounds contained in cement.

Ceramic brick is a porous material. In the process of drying the masonry, it passes through itself water solution salt from the cement binder. The water evaporates from the surface of the brick, leaving the salt carried out on the façade (Fig. 6 and 7).

Rice. 6 - Whitish coating on the walls of a brown brick building

Rice. 7 - Whitish coating on the walls of a brown brick building

Efflorescence also appears as a result of atmospheric (chemical) corrosion, various contaminants of biological origin. In large cities or near industrial plants, the polluted atmosphere contains gases that form during high humidity air harmful substances, for example, sulfuric acid, which, in reaction with the calcium oxide hydrate of the masonry mortar, forms crystalline gypsum, which also appears as a white coating on the surface of the brickwork. The process of efflorescence is influenced by atmospheric precipitation, mainly by washing out salts from the masonry mortar.

1. Apply a hard mortar (the mobility of the mortar mixture when laying the front brick should be 4-6 cm) with a low content of sodium and potassium oxides, or hydrophobic and plasticized cements.
2. When storing bricks, contact with the ground should be avoided, protected from dirt and precipitation.
3. Avoid getting mortar on the front side of the brick. In case of contact with the solution, it must be removed from the walls before it hardens.
4. Do not carry out masonry work during rain. During breaks in work, it is necessary to cover the masonry with foil and other waterproof materials from rain and other precipitation.
5. Seal masonry joints as much as possible. It is better to do this with the use of stitching. Seams should be performed in accordance with regulatory documents (SNiP 3.03.01-87 p.7.6 (norm 12 mm +/- 2 mm)).
6. You can cover the facade with a protective compound.

If efflorescence still appears, special washing solutions are used, which is also reflected in Fig. 8 and 9.

Rice. 8 - Applying a flushing solution to the wall

Rice. 9 - The effect of using a flushing solution

Conclusion: With proper masonry, in compliance with normative documentation efflorescence can be avoided. But if they nevertheless appeared, then it is possible to deal with them with proven methods. If necessary, deposits on bricks can be removed with slightly acidic facade cleaners such as Penta, Sofeks, Tiprom, etc., with strict adherence to the recommendations for their use.

Video instruction on applying facade cleaners to a ceramic brick wall

Brick buildings are built by people who appreciate the solidity, strength, long service life of the building and its appearance. Brick is an expensive building material, and it becomes all the more offensive when a new building, in the construction of which a lot of money has been invested (which, according to the owner’s calculation, should guarantee excellent quality), suddenly takes on such an appearance as if it was time to repair it a long time ago. White or, even worse, greenish spots and streaks on red brick buildings not only look disgusting - they destroy the brick and accelerate the aging process of structures made of it. Therefore, they must be eliminated immediately. In order to get rid of salt stains, you need to know what they are and where they come from.

Water, falling on the surface of the brick, dissolves the building materials salt, and in dry weather, the water evaporates and the salts crystallize on the surface and form spots.

Causes of pollution

Salts, firstly, are contained in building materials - and in masonry mortar, and in brick, and in antifreeze additives, and in hardening accelerators. And secondly, with precipitation, bricks and sea salt can get into the brick if the building is near the sea, and emissions from industrial production (these salts can have a greenish color).

Crystallized salt corrodes the surface of the brick, and it begins to crumble.

Why is salt not visible on the brick when it is purchased or immediately after the building is built? In order for salt to appear on the surface of a brick, water is needed. She falls on a brick building during the rain. And brick is a highly porous material that can absorb enough a large number of moisture. Getting inside the brick, water dissolves the salts contained in the building materials, and the salt gets to the surface due to the fact that in dry weather, the moisture with the salts dissolved in it moves to the surface, on which the moisture evaporates, and the salts crystallize after evaporation of the moisture and form spots. and drips.

Crystallized salt corrodes the surface, and it begins to crumble, and wind and precipitation contribute to "weathering". Salts crystallize not only on the surface, but also inside the material, and therefore the destruction they cause is much greater than it might seem at first glance. Accordingly, the sooner the salt can be removed, the better the structure will be preserved.

Types of salt stains and their removal

Efflorescences are readily soluble and sparingly soluble. That is why you can hear the opinion that salt stains from bricks can be easily removed with water. Water can only wash off easily soluble salts, and even then not all. Some readily soluble salts, getting on the surface, can become sparingly soluble upon contact with air (therefore, they are washed out of the brick with water, and they cannot be removed from its surface with water).

Easily soluble include:

• sodium and potassium carbonates;
• chlorides of sodium, potassium, calcium, magnesium and barium;
• sulfates of sodium, potassium, magnesium, aluminum and iron;
• nitrates of sodium, potassium, calcium, aluminum, iron and barium;
• phosphates and silicates of sodium and potassium.

The insoluble ones include:

• calcium, magnesium, iron and barium carbonates;
• barium sulfate;
• orthophosphates of calcium, iron and aluminum;
• pyrophosphates of calcium, iron and aluminum;
• calcium silicate.

Due to what to do chemical analysis not everyone can afford efflorescence, and ordering such an analysis will require both time to find a laboratory and money, it makes sense first of all to try to wash a small area hot water with a brush and evaluate the result after drying.

To remove poorly soluble salts, there are special cleaners - the so-called "washes".

Slightly soluble salts can be washed off with water using a roller.

There are quite a lot of them on our market - both Russian and imported. Russian washes are no worse than imported ones, but are much cheaper. They are neutral, slightly acidic and acidic. Brick can be cleaned with all these washes, but it must be borne in mind that neutral ones are suitable for cleaning from weak efflorescence, and with acidic and slightly acidic ones, you need to work carefully, and if the solution gets on your skin, immediately rinse the area with water. An acid wash cleans bricks contaminated with sparingly soluble salts. In order to use a wash, you will need:

• brush;
• roller;
• hot water;
• protective glasses;
• gloves.

Before diluting washes, you need to read the instructions on the package, dilute a small amount in accordance with the instructions, try to clean a small area and evaluate the result. The solution must be applied to the brick, left for 20-30 minutes to dissolve the salts, and then washed off with hot water using a stiff brush (if possible, it can be washed off with water under pressure). If the result is not satisfactory, then you need to increase the concentration of the solution.

Masonry waterproofing

By covering the brick surface with a water repellent, you protect it from corrosion, frost and fungus.

After it was possible to remove salt stains with water or a cleaner, it is necessary to treat the surface with a special water-repellent impregnation- hydrophobic. This impregnation will not allow the material to absorb moisture, and without it, the appearance of salt stains will become impossible. Hydrophobization is a common way to protect building structures from moisture. Its difference from waterproofing is that hydrophobization retains breathability, and the material "breathes". In addition, hydrophobization increases:

• corrosion resistance by 1.5-2 times;
• frost resistance by 3-5 times;
• imparts antibacterial and antifungal properties.

And if you add a water repellent to the masonry mortar, it will increase both the strength and plasticity of the mortar (therefore, it is more convenient to lay bricks with such a mortar). Silicon-organic (silicone) water repellents are considered the most reliable. They are water-soluble, organic-soluble and aqueous. The most economical of them are water. There are water repellents that can be applied to a wet surface, there are water repellents, after which the surface can be painted.

Apply the water repellent to a cleaned and dried surface with a brush, roller or sprayer. Water resistance increases within 5-11 days, even if it is raining and snowing outside. After drying, the surface acquires water-repellent properties that last five or more years, depending on the climate and the quality of the water repellent and brick.

Removal of especially strong efflorescence

If the salt concentration is too high, then it cannot be removed the first time even with an acidic cleaner. If this happens, then you need to treat the surface with a water repellent, and after a day, apply a cleaner and wash off the salt stains with hot water (at a temperature of 10 ° C). The applied layer of water repellent will prevent further leaching of salts, and stains will not reappear. After drying, a final layer of water repellent must be applied to the surface.