Dampness in bricks is one of the most common reasons for its repair. In order to avoid progressive degradation, it is necessary to choose an input method. However, not all of them represent an effective solution. About how to remove moisture from masonry with a long-term result, we talked to Ing. Anton Liško, managing director of ELCOP, sro
What are the most common causes of structural degradation that require remedial measures?
The most common causes of damage to buildings are visible and hidden faults that allow water (moisture) to penetrate the structure of the building. Water reaches the building once or permanently. Permanent ingress of water into the building can be caused by damaged, absent or inconsistent insulation. Further penetration of water into the building structure may be caused by installation failure, properties of the building material, imperfect drainage or inflow of rainwater into the building.
Which of the currently used rehabilitation methods do you consider to be the most effective?
There are several remedial technologies on the market that are used to combat voodoo. Among the oldest we earn mechanical interventions, which include air isolation systems, electrolysis and electroosmosis, magnetokinézu, or cutting of buildings. Among the newer ones are chemical isolations in the form of injection. However, not all methods are effective. I introduce some examples:
– Air conditioning systems (vzduchové channels) ensure air exchange, and thereby ventilate vaporized moisture from the surface of the masonry. It is an imperfect solution and a lack of combating moisture in the building, in the vast majority of cases this technology does not solve the problem of moisture, only to a small extent it reduces its consequences.
– Elektrolýza and elektroosmóza are technologies used since the 1960s, based on the creation of an electroosmotic current when an electric field is created. It is necessary to build electrodes to the brickwork, one of which is charged positively and the other negatively. The current density of the generated electric field and the thickness of the material have a great influence on the function. Due to unsatisfactory results, these methods were used in combination with other remedial methods.
– In magnetokinesis (called by the mills and sold as electroosmosis!) according to the manufacturers, the device emits waves that penetrate to the brickwork and supposedly magnetoscopically affect the electromagnetic field and the orientation of water molecules, which reverses the electric potential in the brickwork and the rising water travels to the foundations. The introduced effect of this method was not proven by any product, but in the boardroom, this method is considered speculative.
– Mechanical insulation is made by cutting the masonry in its entire cross-section and inserting an insulating material that prevents the penetration of moisture through the masonry. Insulation materials are usually installed in lengths of 1 m or shorter. The inserted insulating material is different, most often stainless steel sheet, asphalt pás, plastic, for example. polyethylene. ATTENTION! A major disadvantage is the risk of static displacements in buildings, the occurrence of static problems. In the case of multi-floor buildings, the use of undercutting the building is not recommended. In board practice, this technology is abandoned due to the emergence of cracks and narúšanie staticy stavby. In many cases, when the statics of the building are disturbed, it is necessary to spend a lot of financial resources on its stabilization.
– Chemical insulation creates an additional barrier, preventing the transfer and further penetration of moisture to the masonry. Chemical insulating barriers are created by applying injection material to the brickwork. The life of such a barrier depends on the type of injection material, the application method and its chemical properties. Životnosť najnejnej kajlenich hmôt je krátka, zaraďujeme sem mátye silane/siloxane. Up to the middle category patria epoxid-polyuretánové resins. To the group with najvyššou quality patria polyakryláty, napr. WBg, the skin is applied with a pressure pump. When using injectable materials of the highest quality, the life of the barrier can reach more than 30 years.
On what principle is the healing method of high-pressure injection, which you have in your portfolio, based on?
Sanačná metódá is based on hydrophobization of masonry with the creation of an infusion screen as an isolation barrier against the passage of water. We create an insulating barrier by applying polyakrylátove insulating material WBg to the brickwork. The WBg injection mass is applied to the previously prepared and cleaned injection wells with a valve, a valve and a pressure pump under a pressure of 2.5 bar. After application, the valve is closed, the excess parts of the valves are removed. Valves are spätnou klapkou sa zaomietajú, they will not be seen in the future.
What is the effect of the individual components of the injectable substance you are applying?
One of the excellent properties of the material compared to competing materials is its rozpinavosť. In the subsequent reaction of the WBg injection mass with water, it gradually expands and penetrates cracks, pores, and even the capillary system of the masonry. This property of the injection material WBg is a great advantage over the competition, since even after 10 years WBg can react elastically to changes in the masonry, pressure and the appearance of cracks or microcracks through which water could penetrate.
What type of masonry is this method suitable for?
The introduced technology of application of polyakrylátove material WBg to masonry is suitable for all types of masonry, such as masonry buildings with fired, unfired brick, porobetonu, concrete, but also for masonry buildings with stone.
In what cases would you not recommend its use?
The use of introduced technology is limited in parts of buildings below the ground, such as basement buildings, pubs. If the perimeter structure of the building is smaller than 250 mm, it is not possible to use the introduced technology, but even for this problem there is a solution in the form of the construction of vertical insulation with edge injection technology.
If the masonry diagnostics is running and the selection of the application method is correct?
In the event of any intervention in the building, it is necessary to carry out expert diagnostics and find out the cause of the problem. Diagnostics consists of ascertaining the actual condition, visual inspection of the building from the exterior and interior, studying the project documentation, analysis of the used insulating materials and the preparation of the insulating layer, as well as the recommended sampling and chemical analysis of water-soluble salts, which are sulfates, chlorides, carbonates, and findings pH and level of construction.
How quickly does the masonry dry out after applying the injection material?
Brick drying is the process of water evaporation from its surface. The water evaporates gradually but slowly. The length of brick drying depends on the degree of moisture, the type of construction material, the thickness of the material, the degree of salting, and the placement against the terrain.
When is it possible to realize surface modifications?
Surface treatments – omietky – can be applied after drying, usually after three to six months, depending on the previous conditions.
What surface treatments do you recommend to implement after drying the brickwork?
First of all, we recommend applying quality repair plasters that ensure adhesion to the surface and evaporation of moisture. The arrangement of the pores of quality repair plasters also creates an accumulation layer for water-soluble salts. With long-term experience, we recommend the sanitary plaster system from the company EPASIT®.
Sanacné plasters are applied in three layers, sanacná prednástrek, sanacná omietka WTA, sanacná stuka as final surface treatment, color treatment sanacným naterom. The sanitary plaster system designed in this way will ensure the plaster has a long life.
Source: PR article ELCOP