Why add liquid glass to concrete

To date, there are many ways to prepare cement mortars. The easiest is cement-sand with the addition of crushed stone of the desired fraction. However, to give the material of certain properties, make special additives. In particular, one of the most popular components that are used in the composition of the solution is liquid glass, which this article is devoted to.

On the photo - packaged liquid glass in different containers

General information

Liquid glass (silicate adhesive) is an aqueous solution with potassium and sodium silicate, which is obtained from silica. Externally, it is a thick, viscous yellowish-white liquid.

In the industrial field, liquid glass is most often used as a component for the production of bricks and various concrete products used in corrosive acidic environments. However, silicate glue has found application in concrete solutions used for domestic purposes. Next, consider in more detail what gives its use.

Liquid glass

Features of the use of liquid glass

Like any other additive, the component in question should be used very carefully and only when it is necessary to obtain certain properties from concrete. It is also very important to observe the proportions of liquid glass in concrete.

The fact is that the amount of added “glass” is inversely proportional to the time the solution hardens.

Mortar-treated concrete well rings

Scope of concrete with liquid glass

So, the use of liquid glass in concrete allows you to make the material more moisture-resistant and durable. However, in some individual cases, its use is particularly justified.

Next, take a look at the main ones:

  • In case of emergency sealing up cracks through which water flows. If the content of sodium silicate is about 50 percent, the concrete mixture hardens within a few minutes, which is extremely important in such situations. The quality of the seam in this case will depend on the depth of the crack, the flow of fluid that flows out, etc.
  • When decorating the walls outside with their own hands. Since there will be no direct direct contact with water, the additive will improve the water resistance and durability of the finish. In this case, the content of silicate glue should not exceed three percent.
  • In the manufacture of building mixture for laying in cellars, basements and other areas that must be isolated from moisture.
  • During the construction of structures that will be in contact with acidic media or will be used in high-temperature facilities. This is due to the fact that such a mixture is well resistant to high temperatures and acids.

It must be said that the addition of sodium silicate does not increase the cost of concrete, since the price of the additive is rather low. Therefore, its use is more attractive from an economic point of view than the use of other alternative formulations.

Water resistant concrete made using liquid glass

The main mistakes of application of the additive

Improper use of the additive can only spoil the material, degrading its characteristics.

Here are the main mistakes that people often make:

  • The addition of liquid glass to concrete in excess of five percent of the solution. In this case, the strength characteristics of concrete deteriorate. In addition, it increases the time of hardening, which complicates the process of laying.
  • The addition of sodium silicate to the solution intended for pouring the basement causes uncontrolled shrinkage processes.
  • Adding liquid glass to concrete, which is intended for paving or concreting roads inside households. The fact is that the water tightness of the mixture with the addition of sodium silicate can be called conditional. In fact, its chemical properties of liquid glass is soluble in water. As a result, during prolonged contact with precipitation, the upper part of the layer will gradually leach out, and the remaining layer will become loose and easily destroyed.

As a result, when performing foundation and road works, it is more expedient to add special waterproofing additives intended for these purposes. Their basis is resistant to water, moreover, they do not affect the curing time of the solution, respectively, do not change the strength properties.

Обратите внимание! Liquid glass нельзя добавлять в готовый раствор. Предварительно добавка разводится с водой и вливается в сухую смесь.

Concrete coating with liquid glass

It must be said that liquid glass is used not only as part of the mortar; often, concrete is treated with liquid glass to provide the material with water repellency. The fluid penetrates well into the pores and thus provides reliable waterproofing. At the same time, due to the special crystal lattice, the vapor permeability of concrete is preserved.

Putting liquid glass on a concrete surface

Concrete waterproofing liquid glass is performed in the following order:

  • First of all, it is necessary to prepare the surface - clean it from dust and dirt. Sometimes the surface must first be leveled. In such cases, grinding or even cutting of reinforced concrete with diamond circles is used. For example, this procedure may be needed to level the foundation.
  • Then, using a brush or roller, the liquid is applied to the prepared surface in an even layer.
  • After half an hour, the concrete is re-impregnated with liquid glass.
  • Then a protective waterproofing layer is applied. To do this, the cement is mixed with sodium silicate in a 1: 1 ratio. The composition is immediately applied with a thin layer to the surface.

This procedure is completed. If the instruction has been followed, the concrete surface will be reliably protected from moisture.

Waterproofing the basement with liquid glass

In this way, waterproofing foundations are most often performed, however, it is allowed to cover the concrete floor with liquid glass.

Tip! Before proceeding with the application of the waterproofing layer of the foundation, you must perform all the mechanical operations with it, which may be required later. For example, it may be diamond drilling of holes in concrete, for the behavior of communications.


Sodium silicate is able to improve the properties of concrete and in some cases is an almost indispensable additive. However, it must be used correctly. Otherwise, the material properties will only deteriorate. From the video in this article, you can get additional information on this topic.

Add a comment