During construction and in the process of operation, buildings and structures are constantly exposed to various atmospheric influences, temperature extremes, and the adverse effects of dust and gases.
Often, efflorescence (efflorescence) appears on the brick surface of the wall, significantly worsening its aesthetic appearance, destroying the material from the inside and, thereby, reducing the strength and reliability of the structure of the entire building.
Where could efflorescences come from, what caused their appearance?
Efflorescences are water-soluble salts that could be found both in the water used to prepare the masonry mortar, cement, and in the material itself from which the brick is made.
The appearance of efflorescence cannot be affected by either the color or texture of the brick, or the thickness or shape of the seam. One of the points that you should pay attention to is the quality and density of the brick itself. The higher the degree of density of the brick material, the less efflorescence can form. A material with a higher structure density has fewer salts in its composition, it absorbs less moisture, and, consequently, salts with masonry mortar. After performing masonry work, there will be less salts in such a material, therefore, giving up moisture, a smaller amount of efflorescence will form on the surface. With temperature changes or precipitation, the formation of efflorescence in this material will be slowed down, and the sun, wind and water will wash away their negligible amount from the facade. In addition, the material with a lower density, in general, has a large quantitative content of lime inclusions, which will greatly affect the intensity of the appearance of white spots on the surface of the brick.
Masonry mortar plays a large role in the likelihood of efflorescence. For high-quality construction work, especially when laying face facing bricks, it is best to use ready-made masonry mixtures. When purchasing them, do not try to save money, pay special attention to the composition of the components included in it. Many manufacturers, reducing the cost of masonry mixtures, add a cheap plasticizer – lime to their composition. After setting and hardening of the solution, it will remind of itself. Pay attention to the brand of cement used in the composition of the masonry mixture, it should be exclusively Portland cement (PC) or white cement (BTs), and not the cheaper Portland cement (SHPC). Portland slag cement contains slags that will contribute to the formation of efflorescence.
Another factor that affects the appearance of efflorescence is water. When preparing the masonry mortar, water with a minimum salt content should be used.
The appearance of efflorescence can be affected by insufficient waterproofing of a brick wall from the foundation or roof, during which moisture seeps from the roof or capillary “sucking” from the foundation.
In order to prevent the appearance of efflorescence on the surface of the wall material, it is recommended to follow a few simple rules:
- when performing masonry work, at the end of the shift, cover the brickwork from above with waterproofing (roofing material), pressing the material from above, but without wrapping the masonry. Do not allow moisture (rain, dew, snow) to enter the horizontal plane of the brickwork.
- when using cement-sand mortars, use high-quality plasticizers, not lime;
- during construction work in those places where window openings are planned, their lower horizontal part must be covered with waterproofing material to prevent moisture from entering before the installation of ebbs;
- before starting masonry work, the facing brick, which has a low density, must be pre-treated with a water repellent so that it has time to dry before the start of work. If you use high-quality brick of the Litos trademark, then pre-impregnation with a water repellent is not needed. Do not rush to treat the completed brick facade with protective equipment. Wait a while so that all the excess moisture that got into it during the construction process can come out of the brick. You don’t need to preserve it inside the wall. When you notice that the salt release has decreased, then clean the facade from efflorescence and treat it with special protective compounds.
How to effectively get rid of efflorescence on the facade?
In most cases, you will not be able to get rid of efflorescence with a brush and water. You wash the wall with water, the water washes the next “portion” of salt out of the wall. Careful brushing of the wall surface, especially metal, can damage it, and in some cases destroy the front surface of the brick material. If you do not fight the salts formed on the surface, then under the influence of aggressive emissions and atmospheric action, they are converted from water-soluble into insoluble salts. The latter can only be removed using special formulations. Currently, in a wide range in most hardware stores there are various compositions that can effectively deal with efflorescence. Their formula is designed in such a way that they perfectly cope with lime and salt deposits, with persistent man-made pollution, while not disturbing the surface, appearance and structure of the wall material. Cleansing compounds are produced by different manufacturers and have a different composition, and therefore, they fight efflorescence in different ways. Which composition is suitable in your particular case can only be found out by experience or by contacting a specialist for help.