Insulation of the roof with liquid glass, features of the use of the material, surface preparation and technology for applying the composition.
Advantages and disadvantages of silicate roof insulation
Waterproofing or repairing the roof with liquid glass has undeniable advantages, which are as follows:
- The use of this material makes it possible to obtain an effective impermeable coating on a concrete surface with reliable adhesion to the base.
- The low price and ease of use of liquid glass makes this material available to a wide range of consumers.
- A high-quality coating can be ensured with a minimum consumption of silicate material.
Against the background of these advantages, silicate coatings have some disadvantages. One of them is the rapid crystallization of the material when mixed with cement mortar. Therefore, it is advisable to trust professional builders to repair the roof with liquid glass. Another disadvantage of the coating is the need to use roll materials to protect silicate waterproofing from mechanical damage and water leaching. Roofing material, waterproofing and similar products can serve as additional protection.
Consider an illustrative example of the use of liquid glass for a garage roof, which is usually one or more reinforced concrete slabs. In this case, silicate material can be used both for repairing the floor at the stage of preparatory work, and for the subsequent waterproofing of its surface.
To prepare the roof for the application of a waterproof layer on it, first of all, you should choose warm and dry weather, the forecast of which for a week is completely easy to find out. After all, the work can last more than one day.
You need to start it by cleaning the roof to the concrete slab from the old leaking coating. It is not recommended to lay new material on top of the worn-out insulation, as it will most likely lie unevenly, not to mention the tightness of its adhesion to the base.
For work you need a knife, ax, hammer and chisel. Cutting and chopping tools must be properly sharpened beforehand. With an ax, deep cuts must be made in any direction on the old surface over its entire area. Then the old insulation can be ripped off by prying it off with a knife. If it separates poorly in some places, a chisel or a regular chisel will help.
Roof leaks are often caused not only by damage to the waterproofing, but also by defects in the concrete roof slabs. After removing the old coating, they can be seen. If cracks are found in the concrete, the slabs will have to be repaired.
The method of sealing cracks depends on their size. Cracks over 5 mm wide can be repaired with polyurethane foam. To do this, the problem area must be cleaned from dust with a brush and slightly moistened: this procedure will increase the adhesion of the filler to the base. After filling the crack with foam, give it a few minutes to harden, and then carefully cut off the excess material protruding above the surface of the board with a knife. A layer of cement mortar or tile adhesive should be placed on top of the foam-filled crack. Smaller cracks can be removed with liquid glass.
If the edges of the roof slabs have collapsed, they must be repaired. For this, the concrete surface on the chips must be cleaned of dust, and then treated with a penetrating primer. After it has dried, the damaged edges of the slabs should be repaired using mortar.
In the process of preparing the base of the roof for waterproofing, you need to pay attention to its quality: the surface must be even and even smooth. If, when inspecting the overlap, bumps are revealed on it, then they should be knocked down with a chisel with a hammer. The found depressions can be filled with a cement-sand mixture. After it dries, the areas of the roof on which the repair was carried out should be treated with a primer.
If places with exposed reinforcement are identified on the surface of concrete slabs, it is necessary to prevent the process of its corrosion. To do this, the outwardly protruding metal rods should be coated with phosphoric acid. If it is not available, you can use a rust converter, which is sold in many specialized stores.
If the roof does not have a slope necessary to drain precipitation, it must be created before waterproofing. This will require a cement-sand mortar. With its help, make a special screed on the concrete slabs, gradually reducing its thickness in the direction of the desired slope. Its value of 3-5 degrees for a flat roof will be sufficient. After drying, the screed should be primed.
Instructions for applying liquid glass to the roof
When buying liquid glass for roofing, you need to make sure of its quality. The packaging of the composition must be airtight, since when the material comes into contact with air, crystallization of silicate salts can begin. The product should be gel-like, translucent, free of foreign inclusions and lumps. The seller must have a quality certificate for this product.
Before applying liquid glass to the concrete roof slab, it is necessary to prepare a primer mortar. To do this, the concentrated gel should be diluted with clean water in a ratio of 1: 2, 5 and mixed thoroughly.
The silicate priming solution should be applied to the prepared roof surface using a roller, pneumatic spray or paint brush. After half an hour, this operation should be repeated.
After priming the roof, you can proceed to the coating waterproofing. At this stage of work, you will need a mixture consisting of liquid glass, water and Portland cement. It is necessary to work with it quickly, since the setting time of the composition is limited and is only 10-15 minutes.
The fastest solution will be obtained if you dilute liquid glass with water 1: 1. Smoothing the mixture over the concrete surface should be done with a plastering tool.
After repairing the roof with liquid glass and completing the waterproofing, its surface can be insulated or revetted with roofing material.
Watch a video about liquid glass:
Due to its universal use in pure form or as a part of impregnations and additives, liquid silicate glass has become the most effective material for protecting not only roofs from the destructive action of moisture, but also many other equally important building structures. The main thing in its application is to observe the correct proportions for the preparation of sealing mixtures and strictly follow the technology of their application. Good luck!