The material for facade insulation is laid according to a certain technology. The boards must be securely attached to the supporting surface. It is not enough to limit yourself only to the use of special plastic dowels. A complete installation can be called if mineral wool adhesive has been applied to each sheet. Compliance with this rule is fundamental for a long and efficient operation of the heat-saving layer.
What is the glue for?
Mineral wool slabs, specially designed for vertical walls, have a high density and adhere well to the substrate. But due to the irregularities of the latter, channels are still formed between it and the insulation, through which the through air passes freely. This reduces the thermal insulation properties of the cake. Basalt-based mineral slab adhesive helps to solve the following tasks:
- It is a reliable retainer of insulation, not allowing it to move under its own weight under conditions of natural shrinkage, temperature changes in the walls of the building.
- Blocks the channels for the movement of cold masses under a layer of stone wool.
A high-quality product itself must have thermal insulation properties so as not to become a cold bridge for the passage of the dew point into the body of the supporting structure.
Varieties of fixing compounds for mineral wool
It is possible to classify all known ligaments for fixing insulation mats according to the following criteria:
- Internal composition - this parameter determines the ability of the material to create adhesion to the structure of basalt wool and to the base of the wall.
- Mechanical strength - the stronger the hardened fixing mass, the larger the weight of the sheets it is able to hold.
- Temperature application - there are mixtures that can be effectively operated in harsh winters with very low thermometer readings.
- The speed of hardening is a parameter that affects the ease of installation.
- Execution - there are dry compositions or in the form of foam.
For the most part, the manufacturer strives to create universal adhesives for mineral wool on the walls, which are convenient to use in any conditions.
Dry mix
A free-flowing product requires connection with water to be put into working condition. It has a complex composition based on cement and various binders. Fiber of inorganic origin is present in the structure as a reinforcing component. The dry binder is not a combustible material and can be used to insulate buildings of any fire hazard category.
The solution has a certain period of hardening and enables the builder to align the insulation plates in a timely manner, ensuring the comfort of work.
Polyurethane foam
Mineral wool adhesive on a polyurethane basis goes on sale in cylinders for a mounting gun. By the action of compressed air, a stream of foam through the tube goes directly to the sheets of stone wool.The structure of polyurethane allows it to increase its volume upon contact with the atmosphere, so a small-looking cylinder can hold several liters of working mass.
Mounting foams for mineral wool are very convenient to use and significantly speed up the process of insulating building facades.
Positive and negative properties of binders
The strengths of dry-based mineral wool insulation glue include:
- good adhesion to the surface;
- mechanical strength of the hardened material;
- the structure is resistant to moisture absorption and has a large number of cycles of exposure to low temperatures;
- absolute vapor permeability;
- ease of use and relative cheapness of the product.
Dry stone wool adhesive meets environmental standards for direct use in residential construction.
Among the shortcomings, one can note the seasonal limitations of use in work, the need for additional preparation, the original product itself has a large volume and weight, which increases the cost of its transportation.
Polyurethane foam has the following advantages:
- excellent adhesion to any known building materials;
- the structure does not allow heat to pass through;
- work can be carried out in frosty conditions, in wet weather;
- already prepared for the intended use;
- lightweight, convenient balloons reduce the time to apply a layer to the work plane;
- the solidified mass does not absorb water.
The disadvantages of glue for basalt insulation include the fact that polyurethane foam is a combustible substance, it is less durable than the dry fraction, and has a high cost.
Parameters of technical and operational properties
To select a glue for glass wool for a specific insulation task, it is important to know its characteristics. They are usually indicated by the manufacturer on the packaging and can be easily found. Technical ones give an idea of the binder, the density of the structure, the consumption of liquid in the preparation of the working solution, the consumption of glue per square of the surface. The operational ones show how the adhesive base behaves, what loads it can withstand, in what environmental conditions it works normally.
Adhesive layer technology
To carry out work on installing insulation on the facade of the building, you will need the following tools and materials:
- builder's trowel (trowel);
- notched trowel;
- long grout;
- electric drill with mixer;
- dry glue for mineral slabs, for example, Ceresit CT180;
- plastic dowels (fungi).
The very first stage before applying the adhesive mass to the insulation sheet is to remove dust, dirt particles, and grease stains from the wall plane. The base must be leveled as much as possible, the cracks must be putty, the peeling plaster must be removed.
After preparation, the main operations are carried out:
- A basement profile is installed along the entire perimeter of the building in a strictly horizontal direction.
- A deep penetration primer is applied to the wall.
- A working solution is prepared - water is added to the free-flowing mixture at the rate of 200 ml per 1 kilogram of glue and mixed with a mixer.
- According to the technology, the solution is left for 3 minutes, and then mixed again.
- Reinforce the working surface of the basalt mat by rubbing across the entire plane of the glue through the mesh with a spatula.
- Using a trowel around the perimeter of the insulation sheet, apply the mass in strips from the edge, five centimeters wide.
- At three points of the center along the length, glue cakes are applied.
- The slab is supported on the profile, applied to the wall and pressed with a long grout.
- The protruding layer of the retainer is removed from the surface.
Until the solution is completely hardened and the mats are properly fixed, it takes about three days, so each plate is immediately fixed with dish-shaped dowels at the rate of 6 pieces per square meter. The next layer of sheets following the bottom layer is shifted in a checkerboard pattern to ensure the integrity of the structure.
Mineral-type slabs should fit tightly with the formation of seams no more than two millimeters.
Glue costs
The consumption of working material mixed with water largely depends on the type of base, the quality of the basalt mats, the working technique of a particular construction team and the brand of glue. Manufacturers of running dry mixes claim that the average cost per square meter of surface is from 4 to 9 kilograms.
In a hot period of time, when the solution dries quickly, there will be more waste, and the consumption will increase.
A brief overview of modern adhesives
EK Thermex - adhesives for thermal insulation boards, which are effectively used for internal work and outside facades. They are suitable for working with mineral materials and well fix polystyrene sheets and reinforcing mesh on vertical and horizontal surfaces. The mixtures are plastic and create good adhesion to brick and concrete substrates and plastered with cement-sand mortar.
Ceresit CT180 - facade glue for insulation based on cement, mineral fillers and polymer type modifiers. The mixture in operation has a low consumption at the level of five kilograms per square meter of surface. Frost resistance of Ceresit CT180 is within 100 cycles, which makes the product a high class. The solidified mass retains its structural characteristics within the temperature range from +70 to -50 degrees Celsius.
Ceresit CT190 - a mixture of this brand is produced in two versions - a winter version and a summer one. The compositions can only be operated in positive temperatures with modes 0 - + 15 and + 5- + 30 degrees Celsius, respectively. The winter mixture, after hardening for eight hours, can be subjected to a temperature drop of up to -5 degrees Celsius.
