Single-component mineral insulations

The properties of sealing mineral mortars allow their wide use in waterproofing. When to reach for single-component slurries?

Mineral sealants are, next to bituminous materials, the solutions most commonly used in waterproofing. Their use allows effective waterproofing of irregularly shaped surfaces. The versatility of grout applications is a derivative of their properties: high adhesion to the substrate, easy processing, high resistance or, in the case of elastic grouts, also the ability to transfer scratches.

Whether to choose a one-component or two-component mortar is generally determined by the price or quality of the product. Meanwhile, each product has strictly defined parameters, listed in the technical sheet, by the way, as well as greater or lesser elasticity, which is a consequence of the admixture of polymers. The more of them, the lower the vapor permeability, and this is an important detail in renovation. Therefore, it is important to carefully study the properties of the mortars, which will allow you to choose the right insulation for your needs and working conditions. However, the choice of a 1-component sealing compound for effective waterproofing performance requires strict adherence to the mortar preparation instructions, especially when it comes to the amount of water added to the dry mixture. This is because introducing changes from the expected quantity standard results in a change in working parameters and a deterioration of the strength declared by the manufacturer.

Application of single-component slurries

– Sub-tile waterproofing, indoors and outdoors, such as on balconies, terraces, showers and bathrooms with floor drains, swimming pools

– Coatings on concrete facade surfaces, in the splash water zone, with a top layer that inhibits carbonation

– Horizontal composite insulation against capillary rising damp in basement walls

– Sealing of building elements, basements, tanks, canals

– Reinforcement and closure of work gaps

The possibilities for using rigid or partially elasticized single-component slurries are relatively wide. They can be used as protection systems against pressurized and non-pressurized water. They counteract capillary rising of water. They are used for vertical insulation, as well as horizontal insulation in foundation and basement walls, thus preventing the possible penetration of moisture from the foundations into the walls of the house. They are used to seal swimming pools, floors and floors exposed to moisture. These mortars show high resistance to mechanical damage and chemicals, and can come into contact with the ground. Some, thanks to the content of active compounds, after penetrating the substrate, react with water and form crystalline substances that fill the pores. This is the origin of their waterproofing properties of up to 150 m water column, used in waterproofing concrete and reinforced concrete surfaces. However, it is worth bearing in mind that this type of waterproofing is susceptible to mechanical damage, so it requires a protective coating.

Properties of one-component sealing mortars

The use of rigid slurries, due to their lack of crack-bridging ability, is somewhat limited. For this reason, single-component mineral slurries based on gray or white Portland cement are increasingly being modified with the addition of polymers, which makes them more flexible. As a result, the division into rigid and flexible slurries once used makes no sense. In fact, the single-component mortars offered today are a successful compromise: they bind hydraulically and are flexible, and at the same time their processing is the same as for 2-component slurries.

Advantages of mineral slurries

– Environmentally friendly, prepared on a mineral basis

– low layer thickness

– Ability to cover cracks of about 1 mm, in the case of flexible mortars

– Stress compensation: harden without self-stress and crack formation

– tightness under pressurized water load

– resistance to aggressive environments

– by limiting the penetration of carbon dioxide into the reinforced concrete structure, provide protection against carbonation of concrete

– good adhesion on non-absorbent substrates

– resistance to aging

– frost resistance

– Preventing the formation of fungi and mold.

Added to this are time- and money-saving executive facilities.

– quick and easy application, quick-setting one-component formulation requires only mixing with water

– Application by grouting, by filling or by spraying

– the possibility of applying the material to wet substrates

– laying ceramic cladding directly on waterproofing mineral mortar, without the need for additional coatings to protect the insulation

Method of application of mineral sealing mortars

Powder formulations obtain the form of an emulsion when mixed with water. The mixture, mixed with a slow-speed drill, can be applied with a wide brush, trowel or by spraying. In the latter case, units for spraying, such as DESOI SP-Y or BMP 6, are ideal.

Due to their water content, mineral sealing mortars should be protected from frost. They can be used at temperatures from +5 to +30°C, keeping in mind that the mixtures prepared for use behave differently at different temperatures. For example, in hot weather, the mortar will dry faster, so smaller portions should be prepared.

Non-elastic masses can be applied to the surface of foundations or walls only about three months after their construction. This is because the walls must first settle. This does not apply to elastic masses.

Single-component slurries in the bathroom

Flexible mineral single-component slurries are quite expensive, but they are used in both larger structures and single-family homes. In a domestic environment, the rooms that require waterproofing are certainly the kitchen, laundry room and especially the bathroom. Here, the so-called ” wet zones“, i.e. the area around sinks, bathtubs and shower stalls, are exposed to direct water.

Before applying the sealant, the substrate should be cleaned of dirt and dust. It can also be moistened with water, so that it is not drawn off too much from the mortar later, or primed. Application of the grout should be done in two stages. Ideally, the first layer should be applied vertically, while the second layer should be applied horizontally. The first layer of grout should be as thin as possible, applied to close the pores in the substrate with a brush, rubbing it into the substrate. After the first layer dries, another layer can be applied. The interval time between applying successive coats should be adjusted according to the manufacturer’s recommendations.

During the application of the grout, special attention should be paid to the places of wall-to-floor connections and pipe penetrations. These should be further secured by blending in system sealing tapes and collars. Secure the places near the sewage grates by blending in the waterproofing with floor cuffs.

Sealing single-component mortars, combined with additional elements in the form of tapes and flanges, will allow effective waterproofing of edges at wall and floor joints, as well as water and sewer pipe penetrations. They will certainly work well wherever water works under pressure. Care in this regard will prevent the walls in neighboring rooms from becoming damp and, most importantly, will protect your downstairs neighbor from flooding.

Slurry parameters in foundation waterproofing

When using single-component mineral mortars for foundation waterproofing, it is worth taking a closer look at the technical parameters. This is because they determine the effectiveness and durability of waterproofing. What to pay attention to?

– adhesion to the substrate ≥ 0.5 MPa

– watertightness ≥ 0.3 MPa

– static puncture resistance ≥ 15 daN

– maximum tensile stress ≥ 0.4 MPa

– relative elongation at break > 8%

– resistance to substrate cracking ≥ 0.5 mm

According to the Technical Approval Recommendations (ZUAT-15/IV.13/2002 “Cement-containing products for waterproofing coatings”), these are minimum requirements, so you can easily find slurries with adhesion to the substrate above 1.5 MPa and crack bridging of 1.5 mm.

Single-component slurries on balconies and terraces

The properties of elasticized single-component mortars, including frost resistance and the ability to equalize stresses, make them (along with two-component grouts) an excellent solution for under ceramic cladding, both on horizontal and vertical surfaces, and also outdoors, such as on balconies or terraces. They are also just as easy to work with, by applying on the sloping layer with a brush, roller, trowel or spray method.

Mineral single-component mortars, due to their wide area of application, are an increasingly versatile material. The choice is not made easier by the diverse market offer of such manufacturers as Sopro or Sika. However, when deciding on a specific waterproofing method, it should be remembered that only by buying a ready-made system solution can we be sure that everything will work as it should, guaranteeing complete waterproofing.

Compiled by: the Editors of IzoForum