Over the past few years, the popularity of “porous” blocks made of aerated concrete, namely gas and foam blocks, currently actively used in the construction of buildings and residential houses, has greatly increased due to their greater availability and practicality, if you, of course, know all the nuances and subtleties when working with them.
And having chosen them as the basis for building material, the next urgent and no less important question for you may be how exactly the masonry will be made. The use of cement mortars in the construction of structures from this type of blocks is not only morally outdated, but also simply impractical, since the cost of cement will be quite high, given the considerable consumption of the mixture. This is mainly due to the fact that blocks, having a “porous” structure, during the solidification of the solution, suck out most of the moisture from it, making the masonry less durable.
That is why these days, when building using gas or foam blocks, most craftsmen in their field prefer special glue. Naturally, it comes in different types, brands and structures, and it is better to use a certain glue for a particular type of block.
So, if you decide to start building housing and do not know which glue is better to choose, then pay attention to this article, which presents several tips to help you with the choice.
Naturally, the glue for laying cellular blocks comes in the form of a dry mixture from which it is subsequently made. Such a mixture is always based on Portland cement, which is essentially a very fine quartz sand, thanks to which the strength of the already hardened composition is achieved.
In addition to it, various modifiers are also present there, which retain moisture, allowing the glue to harden correctly, and also prevent cracks, which is also completely undesirable. The plasticity of the mass, which allows the composition to fill all cavities, increases various polymer additives, which in turn increases the adhesion between the block and the mortar, ensuring the strength of the structure.
Types of glue
The construction process is almost a year-round business and you never know what kind of weather it will be in, be it a hot summer or a snowy winter. Of course, in most cases, many builders and construction companies try to plan their work, but if you do not want it to stand still in a certain season, then manufacturers of building materials and in particular adhesives have provided the market with two types: summer and winter.
The peculiarity of this mixture is white cement, and it sets within two hours after adding water, so you need to carefully monitor this. Naturally, this glue is used in construction in the warm season, and the operating temperature is considered to be from 5 to 30 degrees Celsius.
From the name it can be judged that this mixture is used to work in colder weather, with temperatures from +5 to -10 degrees Celsius on average. In fact, this mixture has the same composition, but in addition to the main components, it also includes antifreeze. You need to dilute the mixture with water, which, according to the instructions, should be heated to 60 degrees, and such a mixture solidifies in just 30-40 minutes, so it is best to knead the glue in small portions and work quickly.
Solution preparation proportions
Basically, professional builders always know what proportions of the constituent parts are needed for a certain amount of the mixture, but if suddenly you are just beginning to be interested in this topic, you can always find a “recipe” for preparing a solution on a bag with the composition. The rules for preparing the mixture will also be located there.
But if for some reason they were not there, then it is worth noting that they are quite simple and will be available to absolutely everyone:
- pour the contents of the bag (about 25 kg) into a clean container;
- pour in about seven to eight liters of water;
- using a drill mixer, stir the mixture at a low rotation speed, bringing the solution to a homogeneous state;
- after five minutes of “ripening” of the solution, it can be used.
This is what the standard instructions for preparation look like, and it will be quite simple to check the plasticity of the mixture, you just need to apply it with a spatula to the surface of the block and see if it spreads. When thickening, the glue can always be stirred with a mixer, but still you should not keep the mixture unworked after more than 2 hours.
It will also be important to note, as already mentioned above, that the technology for preparing glue from the winter composition is quite different from the main one as follows:
- the water must be hot (at least 60 degrees Celsius);
- the temperature of the finished working mixture should not fall below +10 degrees;
- the life span of such a solution at sub-zero temperatures is no more than half an hour;
- never apply glue to blocks covered with frost, frost or snow.
First of all, it is worth noting that when working with foam blocks, the first row is always placed on a cement mortar, in order to avoid various (probably possible) unevenness of the foundation, and glue is used from the second row.
During the masonry process, if you work with ordinary, standard blocks, then the glue must be applied not only to the horizontal edges, but also to the vertical ones. In the case of using blocks with a tongue-and-groove connection, the application of an adhesive solution to the vertical ends is optional, or even unnecessary.
Naturally, the blocks themselves immediately before laying are also best prepared by cleaning them from dust and possible fine dirt so that the glue is applied to an absolutely clean surface.
Advantages of using glue
The use of glue for laying blocks of aerated concrete has a number of positive features, which in turn affect many more or less important indicators, both at the construction stage and ultimately.
Among the main advantages are the following:
- the ability to achieve the minimum thickness of the seams, which in turn practically excludes the formation of “cold bridges”, which prevents frost from getting into the house;
- taking into account the same small thickness of the joints, the consumption of the adhesive mixture comes out much less than that of the cement-sand mixture;
- time savings achieved by the reduced labor intensity of production and preparation of a solution that is required in small quantities;
- there is no need for any bulky mixer, everything is done by hand using a construction mixer or a drill with a special nozzle;
- the heat and sound insulation properties of foam block walls also increase;
- excellent moisture-resistant qualities of the mixture exclude moisture absorption, and, consequently, the formation of fungus, mold, etc.;
- production becomes much easier, and thanks to smooth walls, the cost of finishing work also decreases;
- and, of course, all the components that make up the mixture do absolutely no harm to the human body;
As for the disadvantages, in terms of the direct use of the adhesive mixture, they are not. But the cost of these compositions is still relatively high, so at this stage they are mainly used for small buildings.
However, despite the fact that the cement mortar can be much cheaper, with the correct geometry and accurate calculations, you will most likely be able to save a lot, since with the above advantages and high plasticity of the mixture, the glue on the masonry can take up to six times less than the cement mortar … And here you don’t need to be a mathematician to calculate the difference in costs, so this disadvantage is also very ambiguous.
The best manufacturers of adhesives
So, you have decided on the use of glue for the masonry of your future home or other building and it is time to choose the composition on which you will assign one of the most important missions, namely the strength and integrity of the structure.
Today, the building materials market is full of various companies and brands, and the category of mixtures is not an exception at all, providing a fairly wide selection. So for a more optimal solution, it is worth considering the three best and most popular options, from world leaders and simply proven brands.
One of the most popular brands of building materials, mixtures and other things is the Ceresit brand, and it deservedly occupies high positions, thanks to its multiple recommendations and its exceptional quality.
Made on the basis of cement with mineral fillers and organic modifier, the Ceresit adhesive mixture is perfect for thin-layer masonry of external and internal walls made of gas or foam blocks.
This adhesive is produced in bags weighing 25 kg.
Also, a fairly popular solution among many construction companies and professional builders themselves are compounds from Knauf, which, thanks to their plaster base, provide high and durable adhesion quality.
The eco-friendly composition of Knauf Perlfix glue does not have any adverse effects on humans, and its plasticity allows you to quickly level the blocks.
This adhesive is produced in bags weighing 30 kg.
Excellent dry mixes suitable for foam and gas blocks can also be provided by IVSIL Block. This glue is well suited for both groove and ordinary blocks, and this glue mixture contains various imported polymer additives that significantly increase adhesion (adhesion between the block and the glue).
The big advantage of this mixture is the ability to adjust the position of the blocks for up to 25 minutes, when in many other cases this time is only 3 minutes.
This adhesive is produced in bags weighing 25 kg.