A material that has been used to cover roofs for many years and has excellent performance qualities is undoubtedly slate. It cannot be taken away from its mechanical strength, good water resistance, and resistance to various types of influences, but it also has a significant drawback.
Compared to other modern roofing coverings, playing with all the colors of the rainbow, slate seems unpresentable, and after several decades, it even looks unimportant. But the situation can be improved. This requires painting the slate. With the help of modern paints and varnishes this problem can be completely solved.
You often hear that painting asbestos-cement materials is short-lived, the paint layer crumbles after the first winter, and in general, it is better not to mess with this matter. In response to this I would like to say, when wrong choice material and non-compliance with technological requirements, even a painted wooden door will lose its shine in a year. Therefore, you need to clearly understand how and with what to paint slate. Let's start with choosing paint.
Today, paint intended for application specifically to asbestos-cement materials is produced by both foreign and domestic manufacturers. These are mainly acrylic or silicone based compositions.
The paint is incompatible with other types of coatings; it is applied to a surface pre-treated with silicone primer. To obtain the desired result, two coats are required.
Other companies from Russia, Germany, and Poland are also producing similar paints. Therefore, the choice of material is quite large. The main thing to remember when choosing is that the paint should be intended specifically for slate.
Like any other surface, slate must be carefully prepared for painting; such preparation is carried out in several stages.
Painting old slate that has been in use for a considerable time begins with a thorough inspection.
Pay special attention to northern slopes; moss colonies may form on them; it must be removed.
This can be done using ordinary metal brushes. To facilitate the process, use hand-held power tools with special attachments. However, in this case you must act carefully so as not to damage the slate.
After removing vegetation, you need to check the entire roof for integrity. If detected small cracks or breaks, they should be repaired using a special mixture. This mixture is prepared from:
Only after all defects have been eliminated will it be possible to paint the slate.
The next step is removing debris and dusting the roof surface. You can do this with regular brushes, or you can do it with water. In this case, the slate must then be allowed to dry. Excellent result obtained by washing slate with car washers, such as Karcher. After this treatment, the slate looks like new.
It is advisable to treat the surface with antifungal drugs - this will increase the service life of the future coating, and the slate in general.
The most important part of coating preparation is priming with compositions recommended by the manufacturer. It is this treatment that increases the adhesion of materials and ensures reliable contact between paint and coating in the future. Poor treatment is the main cause of paint peeling, so you need to make sure that there are no untreated areas on the roof.
In addition, the primer reduces paint consumption. Asbestos cement absorbs such materials very well, so painting slate with your own hands on a poorly treated surface can be disappointing (spots with different color intensities will be clearly visible).
It is advisable to carry out painting in cloudy weather, at an air temperature of about 15 degrees Celsius. Such conditions are optimal for the paint to dry and form a reliable coating. We often hear the question, is it possible to paint slate at temperatures close to zero? Some manufacturers claim that their material is suitable for such application conditions.
But is it worth risking expensive material? Moreover, under such conditions, the period for the coating to acquire its properties significantly increases.
Paint application can be done either manually or using sprayers, do what is most convenient for you. It is worth noting that the paint consumption indicated on the container most often does not correspond to reality. In fact, it will come out almost twice as large. Keep this in mind when purchasing paint.
After applying the first layer, it must be allowed to dry. This period different compositions differs, information can be found on the packaging. It is true that in this case, it is worth keeping the painted slate for a little longer before applying the second layer. The fact is that all such information applies only to ideal conditions, and when real work it must be treated with appropriate understanding.
Asbestos-cement slate roofs have been used in construction for decades, and slate is the most common roofing material in Russia. Asbestos cement is an artificial stone material obtained by hardening an aqueous mixture of Portland cement and finely fluffed chrysotile asbestos fibers that reinforce the cement component.
Asbestos-cement products have high mechanical strength in bending, low density, low thermal conductivity and water permeability, high frost resistance, resistance to alkalis, and are also characterized by sufficient biostability. Tensile strength of asbestos-cement slate sheet: in tension - 20...25 MPa, in bending - 27...42 MPa, in compression - 45 MPa or more.
The disadvantages of asbestos cement include: reduced strength when saturated with water, fragility and warping when humidity changes, poor impact resistance.
What and how can slate be processed? so that it doesn’t turn green or black?
In order to get rid of these shortcomings, waterproof compounds are applied to the surface of asbestos-cement products, protecting the material from moisture and mechanical damage, ensuring good water drainage and not retaining dust.
To do this, the asbestos cement sheet is dried to 7...6% humidity, after which its surface is cleaned of dirt, primed and finally painted with weather- and water-resistant painting compounds.
By the way, to increase water resistance and reduce the release of asbestos dust, which causes specific diseases, the back side of the product is also primed.
Painting of slate sheets with perchlorovinyl compounds (PVC, TsPKhV, KhV-161) is carried out at a temperature not higher than +4°C (due to the toxicity of the compounds) and not lower than -20°C.
To do this, first apply perchlorovinyl primer to the surface of the sheet, which dries in 2–3 hours in summer conditions.
The dried surface is painted with perchlorovinyl compounds using a spray gun (preferably brand SO-71A). At mechanized way When painting, the composition must be systematically mixed in the paint injection tank to avoid its delamination. During operation, the distance from the gun to the surface to be painted must be at least 0.5 m; the gun should be moved along the surface evenly, at a speed of about 0.3 m/s.
Slate is painted in stripes. The first stripe is applied from top to bottom, the second to the right of the first, but from bottom to top, the third, like the first, and so on. To obtain a continuous coating (without gaps), it is necessary that each subsequent strip overlaps the previously applied one by 3...4 cm. Typically, two layers of the composition are applied to the slate, and the second layer is sprayed only after the first has dried.
When painting twice with a PVC composition, per 100 m² of surface the following is consumed (kg):
PVC paint - 59;
PVC primer - 15;
Solvent (solvent; R-4; 5% PVC varnish) - 10.
When applying a ready-to-use cement-perchlorovinyl composition (CPVC) to 100 m² of surface, 41 kg of the composition is consumed for the first painting, and 36 kg for the second.
Slate surfaces are also treated with KO-174 enamel, which is disperse system(suspension) consisting of a solid phase (fillers) and a liquid phase (organosilicon varnish KO-85, diluted with a solvent - a mixture of butyl acetate, acetone, xylene and toluene).
As a result of the evaporation of the solvent, the enamel hardens. The drying time of the enamel at a temperature of 18...25°C is about 2 hours. The enamel has good adhesion, so that it reliably sticks to asbestos-cement sheets, and the enamel coating is characterized by high strength and water resistance.
Thickened enamel is diluted with R-5 thinner. Before painting with enamel, the surface is prepared in the same way as before painting it with perchlorovinyl compounds. The slate must be dried before painting, since its humidity should not exceed 8%.
Apply the enamel 2…3 times with a paint brush or paint sprayer. Each subsequent layer is applied 1…2 hours after the previous one. Please note that enamel is toxic, so it is used only for external use.
The slate is also covered with organo-silicate compounds. One of the most durable compositions is composition OS-12-03, which consists of the paint itself (a suspension of organosilicon polymers and inorganic additives in toluene) and a hardener - polybutyl titanate or butyl titanate.
Before use, add a hardener to the paint composition in an amount of 1% by weight of the paint and thoroughly mix the composition in the container for 1 hour using a nozzle with blades. The paint hardens as a result chemical reaction between components. Xylene or toluene is used as a solvent. The coating has good adhesion and adheres reliably to concrete, cement, sand-lime brick, ceramics and metal (with the exception of halogen-containing plastics).
On slate and metal roofs, the organo-silicate composition is applied at temperatures from -40°C to +40°C, using a paint brush, roller or paint sprayer.
The composition dries quickly - in 30 minutes. “Viability” of the composition prepared for application is 24…48 hours. When applying a two-layer brush coating of asbestos-cement or concrete surfaces consume up to 400 g of composition per 1 m². Of course, the composition is applied to the surface, previously cleaned of dust and lubricating oils, by sprinkling with mortar.
When working with a paint sprayer, use a nozzle with a diameter of 1.8...2 mm and form a round torch from the paint.
During the application of paint, it is thoroughly mixed by hand.
Slate asbestos cement sheets are also painted with silicate paints prepared on the basis of potassium soluble glass (K2O mSiO2) with a density of 1.3...1.5 g/cm³. Silicate paints also contain a separately supplied mixture of pigments with chalk, taken in a 1:1 ratio (by weight).
The value m is the ratio of the number of silica molecules (SiO2) to the number of alkali oxide molecules (K2O) and is called the silicate module of glass. For potassium glass, m is 3…4. The higher the module, the higher the quality of liquid glass.
The density of glass depends on its concentration. Often liquid glass comes from the manufacturer with increased density, so it has to be diluted with water.
The required amount of water is calculated by the formula:
U1=U2(p1-p2)/(p2-1000),
where U1 is the amount of water that needs to be added to the solution, l;
U2 - initial volume of liquid glass, l;
p1 and p2 - initial and required density of liquid glass according to the hydrometer, kg/m³.
There are 10 liters of liquid glass with a density of 1500 kg/m³. You need to get a solution with a density of 1370 kg/m³. It is required to determine the amount of water U1 that must be added to the solution. The amount of water added is:
U1=10*(1500-1370)/(1370-1000)=3.5 l.
Before use, strain the composition through a No. 0.25 mesh containing 694 holes/cm².
Silicate paints are made only with alkali-resistant pigments and they have fire-retardant properties. It is impossible to prepare the painting composition for future use, since after a day it becomes unsuitable for further use.
For silicate paints It is allowed to use only potassium glass, since the presence of sodium glass (Na2O mSiO2) causes the appearance of a white coating, so-called efflorescence, on the painted surface.
Therefore, before using silicate paints, it is necessary to check their quality, that is, to determine whether they contain sodium soluble glass.
To do this, take a red clay brick, the five sides of which are painted twice with the paint tested twice. After the paint film has completely dried, the “experimental” brick is moistened with water until completely saturated and placed on the unpainted side. If the soluble glass contains an admixture of soda glass, then after 1...2 days it will appear on the painted surfaces of the brick. white coating and the paint will begin to “chalk” when rubbed with your hand.
The slate surface is primed before painting with liquid glass with a density of 1.41 g/cm³, while the consumption of liquid potassium glass is 27.3 kg per 100 m².
The first painting is carried out with a composition with a density of 1.14 g/cm³, the second - 1.18 g/cm³. The consumption of liquid potassium glass (per 100 m²) for the first painting is 14.8 kg, for the second - 11.1 kg. Let's not forget about the dry pigment mixture, which will require 30.9 kg for the first coloring, and 26.6 kg for the second.
Asbestos-cement slate sheets are painted in warm weather (at positive temperatures), avoiding painting in direct sunlight.
To impart water-repellent properties to the applied film, hydrophobic additives - organosilicon liquids (GKZh-10 and GKZh-11) - are introduced into the silicate compositions intended for the second painting. They do it like this. Diluted liquid potassium glass (density 1.15 g/cm³) is loaded into the mixer, then the required amount of pigments is poured in and the components are mixed until homogeneous, where GKZh-10 or GKZh-11 (commercial 30% concentration) is added.
Consumption of hydrophobic additives is 2.3 kg per amount of liquid potassium glass required to cover 100 m² of slate.
Of the anhydrous compositions for painting asbestos-cement slate sheets, the following brands of paints are used:
White lead thickly ground (MA-011; MA-011-N-1; MA-011-N-2),
Thickly ground zinc white (MA-011; MA-011B; MA-011N; MA-011NV),
Oil paints (MA-011 and MA-015; thickly rubbed special),
Thickly rubbed oil and alkyd colored paints (MA-011; MA-015; GF-013; PF-014),
Oil and alkyd paints ready for use (MA-11; MANN; MA-15; MA-15N; GF-13; GF-13N; PF-14; PF-14N; MA-21; MA-21N; MA-22; MA-22N; MA-25; MA-25N),
Thickly grated lead greens (MA-011-N-2; MA-011-N-3; MA-015-N-2; MA-015-N-3),
Oil and alkyd paints, earthen, thickly rubbed (red lead, mummy, ocher).
All types of primers and the above-mentioned waterless paint compositions for external coatings are prepared only with natural drying oil and diluted only with natural drying oil!
Coloring is carried out in the manner described above. Before coating asbestos-cement slate surfaces protective composition must be completed preparatory work After cleaning them from dust and soot, dry and prime the slate.
I repeat, it is not allowed to paint in dry and hot weather when exposed to direct sun rays, as well as during rain or on a damp surface, you should not work in strong winds.
The most favorable time of year for painting asbestos-cement roofing is the spring months. Painting works are carried out using special ladders that evenly distribute the weight of a person over the surface of asbestos-cement slate surfaces, which eliminates their damage.
All materials from the “Repair and Construction” section
1.Characteristics of slate as a roofing covering
2. Slate roof repair
3. Cleaning the roof
4. Elimination of cracks and replacement of sheets
5. Painting slate
Roofing material such as slate is always popular, regardless of the appearance of new coatings on the market.
It is distinguished not only by its reliability, but also by its affordability. Slate painting is done in order to increase the service life of this roofing coating. Therefore, it is worth understanding how to paint slate and how to paint slate on the roof, as well as how to repair the roof. Detailed instructions with photos and videos of this process can be easily found on our website if desired.
This material, which was once made using clay shale, is one of the oldest materials of a kind. Of course, such natural slate slate is quite difficult to find today, partly due to the fact that it has an incredibly high price (read: “Installation of slate roofing - installation methods”).
However, an artificial version of such a coating - flat or corrugated asbestos-cement sheets - are very widespread today.
Nowadays, other roofing materials are offered that have some relation to slate, for example, Euro-slate, the basis of which is bitumen (read: “Euro-slate - reviews and main characteristics”), metal slate, etc.
But asbestos-cement slate is still the most popular roofing type.
The main advantages of slate:
Slate roofing is, by definition, durable.
This is especially true for roofs where painted slate is used, since the protective film created by slate paint helps to increase the slate’s resistance to various mechanical and natural influences, therefore, the service life of the roof is extended.
In addition, slate is a completely repairable material. So, if any cracks or defects appear on the slate sheets, then there is absolutely no need to redo the entire roof, even if a significant part of the material is completely destroyed.
It will only be enough to replace the damaged sheets, taking into account the size of the slate that was previously used.
In the case when painted slate is used, there is absolutely no danger to health, since thanks to paint it not only increases the reliability of the roof, but also stops the emission of dust, which contains asbestos particles.
No matter how mobile and easy to repair slate is, if any defects appear, repairs still need to be done, and the sooner the better.
Typically repair work consists of three stages:
Repairing a slate roof with your own hands and strictly following the rules of all three stages will allow the roof to last for decades.
Usually, if the roofing material is painted slate, then cleaning the roof will not present any difficulty; you will only need to sweep away all the debris that has accumulated on it.
If the slate sheets are not painted, this can lead to the appearance of moss and lichen on them, which, of course, cannot have a positive effect on both the appearance of the roof and its performance properties.
One of the tools used to clean the roof is a brush equipped with metal bristles. The work can be simplified by using a drill with an attachment similar to a wire brush.
Ordinary water supplied under pressure can also clean slate well.
Compact portable car washes used for cars are perfect here.
The basis for repairing relatively small cracks in slate can be mastic, the base of which is bitumen or a special putty made using chalk and drying oil.
A special composition for repairing cracks may also consist of the following elements:
Liquid elements must be selected in such a volume that the final composition has the consistency of a thick paste.
Due to rapid hardening, these compositions need to be prepared in small portions.
Another option for sealing wide cracks is to glue patches made of fabric onto them.
In this case Right place it is primed, and then a patch is applied to a thick layer of paint, the size of which should be 10 centimeters larger than the size of the crack. Next, the patch needs to be covered with an additional layer of paint.
This same stage of repair also includes the replacement of damaged slate sheets. To do this, special walkways are mounted on both sides of such a sheet, for which ridge brackets serve as fastenings. To move on the roof during repairs, in this case a wide board is placed across these walkways, on which you can walk if necessary.
The nails and screws on the required sheets must either be completely removed or loosened. If nails are being removed with a nail puller, it is important to place a piece of wood underneath the tool.
The required sheet, that is, the one that needs to be replaced, needs to be lifted and a new one placed in its place. It should be located along the edge of the ceiling and move towards the ridge. The new installed sheet is secured with screws or nails.
All professionals agree that painting slate is not only possible, but necessary, as this significantly improves the properties of the roof and extends its service life.
An important factor is the aesthetic appearance of the painted roof.
Therefore, painting slate with your own hands can be done; a more difficult question will be how to paint flat slate. Previously, the standard was used for this Oil paint, despite all the negative nuances of this method (fragility, tendency to rapid destruction).
Nowadays, special paint and varnish compositions are becoming increasingly widespread, which are suitable for painting not only slate, but also tiles, concrete, etc. The basis of such paints is acrylic, due to which these compositions are resistant to low temperatures, solar radiation and precipitation.
This, of course, has a positive effect on aesthetic appearance roof, which will remain so for a long time.
When deciding what to paint slate with, you can choose special paint for slate, called triora. It is resistant to external influences, in addition, it can be used both for slate and tiles, and even to cover the basement of a building.
There are other paints produced by both domestic and foreign manufacturers (read: “How to paint a slate roof: technology”).
Painting slate yourself, that is, without the participation of professionals, is quite possible. Of course, the best option would be to paint the slate sheets before laying them, but this will not be possible during repairs, so you will need to apply paint to already laid sheets.
3 stages of slate painting:
The painting tool can be a spray gun or a paint brush.
Flat slate can also be painted using a roller, size flat slate this allows.
Before applying primer to the slate, it is best to properly treat the coating with an antiseptic solution, which is most often sold in concentrated form and is diluted with water before use.
Using such a solution will prevent fungus or lichen from appearing on the slate. It can be applied either with a wide brush or with any device capable of spraying liquid. It is important to remember about protective equipment - glasses, gloves, a respirator.
A slate primer can then be applied, which often contains acrylic liquid compounds that can penetrate deep into the pores of the coating, thereby giving it greater durability and better adhesion of the slate to the paint.
Painting slate on the roof, watch the video:
Very often, primer from one or another manufacturer is offered along with paint, so it would be better to opt for the same brand. Apply primer in the same way as paint: you can do it with a sprayer or a roller.
Due to the fact that slate is a porous material, painting it without a primer will be uneven, which will certainly lead to excessive paint consumption.
After the primer has dried, you can begin to apply the main coat of paint. It is very important to apply it well to all corners and ends of the coating.
The final coating is designed to give slate roofing a beautiful appearance.
It helps to make the surface uniform and uniform, without visual transitions and paint streaks. This layer can be applied only after the base layer has dried.
The paint used for the final coating is the same as for the main one, the only difference is in its smaller quantity.
The last stage requires approximately one third of the total paint volume, and the base coat - two thirds.
So, it is quite possible to paint slate yourself. This will provide an excellent opportunity to save a significant amount of money, since the services of professional craftsmen are usually not very cheap.
Many people want to update the look of the roof of their home. Thanks to modern technologies It's not that hard to do. The most common procedure – painting with special compounds – allows you to transform the dull appearance of gray asbestos cement sheets into a bright, beautiful and unusual one.
For a long time, slate was a completely self-sufficient roofing material that has proven its reliability for decades. However, if you remember its unattractive gray color, then the question of whether it can be painted has not lost its relevance all this time. Decoration is just one aspect.
Painting solves purely protective problems in practice. Paint protects the roof surface from destructive atmospheric influences; it helps reduce water absorption and increase frost resistance. That is, it can be argued that depending on what paint you use to paint the slate, you can significantly increase the service life of the asbestos-cement roof.
You can often hear that paint for flat slate is very short-lived - one winter is enough and it will crumble. Undoubtedly, this cannot be ruled out, but only for those cases when it is chosen incorrectly. Let's try to figure out what and what paint is best to paint with.
Typically, asbestos is painted with one of the following materials:
The last of them is perhaps the least suitable for asbestos-cement roofing. Unlike the other two, it is less weather-resistant, and also has a rather pungent, unpleasant odor.
Enamel with a quick-drying composition gives the roof an exceptional decorative effect. This finish is resistant to weather conditions and UV radiation. The consumption of this material is 100–150 g per square meter. m. Performance characteristics coatings last for 3–5 years.
It is no coincidence that ACL is mainly used for painting acrylic compositions. It is considered the most durable and safe of the above. After applying the composition, a moisture-proof film is formed on the roof surface, which, if properly applied, does not collapse for at least ten years. Acrylic coatings create a smooth surface along which rain and melt water flows freely and snow melts off, reducing the load on the supporting structure of the roof.
The latter is very important, given the significant load from the asbestos-cement sheets themselves.
It takes more acrylic than a quick-drying composition to cover a unit area - about 0.3 kg per square meter. m. Acrylic compositions
When applying paint to the roof, you must strictly adhere to the manufacturer's recommendations - they are usually marked on the packaging.
The list of materials is much wider.
Before painting the coating, quite labor-intensive preparation is carried out. First of all, each of the sheets is checked for integrity and reliability of their fixation.
Sheets that show cracks or damage must be replaced.
The next step is to carefully clean the roof of any dirt, moss, etc. Asbestos-cement sheets are cleaned of old plaque using sandpaper and treated with an acrylic primer containing a special antifungal component. As a result of the primer, the pores are filled roofing material.
After the primer has dried, apply to asbestos-cement sheets cement mortar. The consistency should resemble kefir. A brush is used to apply the solution. Other tools, say a roller, are not suitable for this.
Dove cement mixture completely dry, the roof is primed, after which the roof is painted.
Is it possible to paint in wet weather, when is the best time to paint? Questions that concern many, especially those who intend to handle the roof themselves. Painting of ACL must be done dry warm time of the year.
The paint is applied in two layers using ordinary painting tools, for example, a spray gun. The second layer is applied to the completely dry first one. Practical experience shows that painting in the spring provides them with long-lasting protection, gives the roof a decorative appearance, and prevents the appearance of moss.
On the domestic construction market slate has remained one of the most popular materials for many years. Today it is used both unpainted (for country houses, for outbuildings and non-residential premises) and in painted form. Last option can add additional aesthetics to your home. However, if you decide to transform the roof of your house, you should choose the right materials. Let's try to figure out how to paint slate, which paint is preferable and why?
Let's start with the fact that most of our compatriots are firmly convinced that only wavy sheets are “slate”, but in reality, this definition Flat sheets of asbestos-cement chips are also included.
What is the best paint for slate?
The modern choice of materials is huge, and this makes it possible to make the roof of a house truly individual. When choosing what to paint slate with, evaluate all the advantages and disadvantages of imported and domestic options and only then make a purchase.
Acrylic paint for slate
The list of undeniable advantages of acrylic or water-dispersed compositions includes:
§ Ability to fill small cracks and provide reliable protection against moisture penetration.
§ Hydrophobicity. Water easily rolls off the painted surface, which makes it possible to work with the composition on flatter roofs.
§ Reducing the load on the rafters. Occurs due to improved conditions for snow removal from slate.
§ You can work with acrylic paint at air temperatures from +5°C to +35°C. The drying process takes 1-2 hours; complete polymerization of the composition takes a day.
If you are looking for how to paint flat slate? Best suited for these purposes acrylic paint. It provides the roof with maximum resistance to weathering and temperature changes.
Fast-drying enamel for slate
This option contains binder, which promotes the formation of a smooth film on the roof surface. A roof painted with such enamel is not only durable, but also has high water-repellent properties and is reliably protected from the destructive effects of ultraviolet rays.
Liquid plastic for slate
This synthetic composition is made on a polystyrene, bitumen or vinyl chloride base. The high popularity of this paint for slate is explained by the ease of its application, as well as its high elasticity, which eliminates the risk of delamination of the coating. Rubber paint contains pigments that prevent the color from losing its brightness for a long time. The only drawback is toxicity. The composition should be applied in special means respiratory and hand protection.
§ Polifarb/Akrofarb (Poland). This composition is based on and dispersion paints, which ensures high drying speed, as well as color saturation and brightness.
§ Kilpi (Finland). This paint is perfect for slate, corrugated sheets, and metal tiles.
§ Eter Akva (Finland-Sweden). This material is resistant to alkaline aggressive environments, is water-soluble, and contains acrylate. It is used for coloring slate and concrete.
How to repair and paint slate
Old slate can last for quite a long time if you take the appropriate measures. Of course, this requires a lot of work, but it is still much cheaper, easier and faster than replacing the roofing material completely.
The slate can be restored. To do this, it needs to be washed, repaired and painted.
The first stage is not as simple as it seems. Rags and sponges will be useless here. And even with hard metal brushes it will be impossible to clean old slate, which has become covered with a layer of moss over many years. Here it is better to use something more serious. In particular, we can recommend a drill attachment in the form of a round stiff brush. Using this attachment, it is quite possible to clean the slate to a condition suitable for further work.
But a high-pressure washer will be even more effective. This tool is used in construction. It can also often be seen among car owners and in auto repair shops. Of course, it is better to use a construction sink, as it has more power.
You cannot skip the stage of cleaning old slate. The fact is that the materials that will be further used for its repair and subsequent protection should not be applied to the layer of debris. In this case, they simply will not be able to properly adhere to the surface and will begin to peel off after a few days.
Old slate often has nasty cracks. It used to be difficult to deal with them. But today new materials have appeared on sale that simplify the task many times over. These materials include bituminous two-component mastics.
If the task is not emergency slate repair to eliminate a leak, but you want to truly improve the quality of the old coating, renew it and extend its service life, then you should not buy and use ready-made mastics. It is better to use two-component ones, which are mixed in a suitable container before use and only then applied to the roof.
There are different types of mastics, and in order to perform slate repair work with their help efficiently, you need to read the instructions that come with them and, most importantly, follow all the recommendations that are set out in it.
After the slate is free of cracks, it is primed. Choosing primers for slate is not easy, since slate is made from complex composition, which may be incompatible with the primer. To play it safe, you can buy an acrylate primer, which is better suited for slate and other similar materials than others.
You can also prime the slate with paint. To do this, you simply need to dilute the paint with clean drinking water in a ratio of one to ten.
As for painting slate, rubber paint is recommended. It is plastic, easily adapts to any conditions, durable and strong. This paint will provide reliable protection for the roof and will significantly extend the service life of the slate.
Domestic slate paints:
§ Butanite (Russia). The composition contains polymer substances and mineral-silica additives. Butanite provides the roof with reliable protection from atmospheric exposure, increases the frost resistance of the surface.
§ Polifan (Russia). The paint is suitable for working on slate, concrete, brick. Its undeniable advantages include durability, color fastness, and wear resistance.
§ Unisal (Belgorod). The composition contains acrylic elements and coloring pigments High Quality. This paint provides a coating that is resistant to UV exposure and the damaging effects of moisture.
If an already installed roof is to be treated, it will require preparatory activities. To do this, you should prepare a brush with metal hairs, an angle grinder or a drill with a special brush attachment, or a high-pressure car wash. The latter option will make the process less labor-intensive and highly efficient.
Using the above tools, we clean the roof from plaque, moss, etc. Next, we treat the surface with an antiseptic, which will prevent the proliferation of fungi and the appearance of plaque. The next stage is primer.
By carefully priming the slate sheets, you can be sure of maximum adhesion of the paint to the surface of the roofing material. In addition, the primer, by filling the pores, will significantly save the paint itself, and the roof surface will become more even.
Before painting directly, the slate must be checked for hidden serious damage by careful inspection. If some sheets are cracked, they need to be replaced. Simultaneously with checking the condition of the surface of the slate sheets, the reliability of their fastening and, if necessary, additional strengthening are checked. Then the most labor-intensive procedure is performed - cleaning and sanding the entire surface, which completely removes dirt and dark deposits. This work is performed using an electric drill with a sanding attachment. Additionally, it would be a good idea to wash the slate with a powerful stream of water from an electric washer.
After cleaning, you must immediately coat the surface with a special antifungal primer, after which, after drying, apply liquid cement mortar (the consistency of kefir) to the roof. The solution must be applied with a brush (a roller is not suitable for this operation). After waiting for the solution to harden, the slate surface is primed again. The pores and microcracks are sealed and the process of applying paint can begin.
Choosing paint for slate
The selection of paint is carried out taking into account the result you want to achieve - a bright appearance with slightly worse durability, or vice versa, excellent performance with calm and discreet tones. In the first case, acrylic enamel is used, in the second, rubber paint or, as it is also called, liquid plastic. Both options have advantages and disadvantages.
Acrylic paint for slate
Acrylic enamel has water base and fills microcracks well, protecting slate from destruction. It also has water-repellent properties, which is important, since rain, unfortunately, does not a rare event in our latitudes and its detrimental effect on the roof surface is most sensitive.
When choosing acrylic paint for slate, you must carefully read the instructions, as it indicates the conditions for its use and lists the surfaces where it should be applied.
Many experts recommend rubber paint for slate as a special composition that creates an elastic protective film on the surface, which prevents paint peeling. It is also good because it adheres perfectly to slate and is convenient to apply.
Rubber paint for slate contains special pigments that do not allow color shades to fade in the sun, so dull gray there will be no roof. A serious disadvantage of rubber paint is its toxicity, so increased attention should be paid to protecting the respiratory system and exposed skin when painting.
Slate paint Condor
Weather-resistant acrylic paints for slate Condor (KONDOR), produced in Belarus under a German license and having excellent characteristics, have proven themselves well, as well as good value price quality. Condor paints are sold in all construction hypermarkets and many stores for summer residents.
Slate painting
So, the roof is prepared, the paint has been selected, you can start painting the slate. And here an important question arises: is it possible to paint slate in damp and humid weather, will this not harm the quality of the work? It will hurt! It is better to paint in dry and warm weather.
Reviews from those who have painted slate themselves indicate that work done on a warm spring day gives the best results and the paint lasts longer after application in the spring than if done in the hot summer. For painting, use a roller, brush or spray; the paint is applied in two layers, with the first completely dry.
If all operations are performed correctly, the old-new slate roof will last for a very long time, and the paint will retain its color and will not crumble even after intense rainfall and temperature changes.
Slate preparation
The process of preparing slate involves cleaning it of any debris. It should be noted that this procedure often requires even new material, since there may be adhered particles of asbestos cement on it, which are invisible at first glance. To remove them, you can use a regular small spatula.
Advice! Before painting a slate fence, you should break through the grass that usually grows along it and interferes with painting.
If the slate has already been used, then it needs to be cleaned more thoroughly. To do this, you need to use a stiff metal brush, treating every centimeter of the surface.
Slate cleaning field, it should be wiped damp cloth to remove dust and small debris.
Padding
The next step is priming. For these purposes, it is best to use an acrylic universal primer.
Instructions for applying it look like this:
1. first of all, the canister with soil must be thoroughly shaken;
2. then the liquid must be poured into a container into which it will be convenient to dip the brush;
3. Next, you need to moisten the paint brush in the soil, lightly squeeze it against the walls of the container and then apply the liquid to the surface of the slate. The soil should be laid down in a uniform thin layer, so it is necessary to avoid drips and large cluster liquids in certain areas.
If you plan to paint flat slate, you can use a paint roller to apply the primer;
4. After the surface has dried, the procedure must be repeated again.
Advice! If necessary to cover with primer large area, you can use a spray bottle or spray bottle.
This completes the priming process.
Selection and preparation of paint
Before you paint flat slate or corrugated material, you need to decide on the paint. Best choice in this case, they are polymer water-dispersed compositions. Moreover, it is necessary to use paints that are intended for covering the roof or facade.
It should be noted that polymer compositions come in three types:
· acrylic;
· silicone;
· latex.
The most durable are silicone and latex paints, however, their price is very high - ~ 4000-5000 for a 10 liter bucket. Therefore, you can use acrylic paint, which is much cheaper, but is also quite durable.
As a rule, water-based paints are sold white and require tinting. This process consists of adding the required amount of tint of the desired color, which allows you to achieve any shade.
As a rule, stores that sell paint and varnish coatings have special tinting machines. They allow you to paint the entire batch of purchased paint in the same color of your choice.
Note! When painting a roof, you should purchase paint coatings not only for slate, but also for other surfaces. For example, anti-corrosion conductive paint Zinga is suitable for fencing and flashings. To paint chimneys, it is better to use fire-retardant metal paints Polistil.
If it is not possible to perform tinting when purchasing paint, you need to independently decide on the proportions of the color, first painting a small amount of the composition. After this, the same amount of color must be added to all containers with paint and mixed thoroughly.
Painting
The final stage is painting, which is performed in the following sequence:
1. Before use, the paint must be mixed;
2. then it should be poured into a container into which it will be convenient to dip a paint brush or roller (if painting flat slate);
3. After this, the painting tool must be moistened with paint, squeezed lightly and applied to the surface. This stage is the most critical, since you need to ensure that the coating is applied in an even, thin layer, and there are no unpainted areas left;
4. When the paint dries, the procedure must be repeated again.
This completes the slate painting process. It should be noted that this operation can also be performed using a spray bottle.
Conclusion
The process of painting slate is quite simple and quick. However, it must be taken into account that the quality of the work done depends on the preparation of the surface. Therefore it is necessary to pay Special attention cleaning slate from dirt and priming.
Paint and primer for slate: Shikril Among the special paints and varnishes produced to protect slate is the acrylic paint Shikril, which is based on organic solvents. This paint is used not only for finishing asbestos-cement slate, but also concrete plinths, cement-sand tiles and other external surfaces that require alkali-resistant painting.
1. “KILPI” - Finnish acrylic coating for roofs, which is produced well-known company Tikkurila. Used for painting tiles, slate, roofing felt, bitumen fiber boards and other materials. Valued for its special elasticity at very low temperatures. One liter of coloring solution is enough to paint no more than two square meters of surface. Finnish slate paint 2. “DACHBESCHICHTUNG” is a German roof coating produced by DUFA. This semi-gloss paint is suitable for complete painting and partial repair of painted surfaces made of clay, concrete or slate roofing tiles. The paint coating freely allows water vapor to pass through, while protecting the roofing material from the effects of precipitation. Features a high degree of adhesion. If the base is professionally prepared, the paint layer can last for many years. One liter of coloring mixture is enough for 7 square meters of roofing. 3. POLIFARB – AKROFARB is produced by the Polish manufacturer of paint and varnish coatings “Debiza”. The paint is made on the basis of acrylic dispersion. It is used for painting not only roofs, but also facades finished with clay-cement slabs or slate. The applied coating dries in three hours. A liter of paint is enough to paint 5-7 square meters of roof surface. Slate paint shades
4. “AKRILAKMA-SLIFE” is a Ukrainian water-dispersed acrylic paint intended for work on slate. Produced by LAKMA in two color options: red-brown and brown. After painting, you get a smooth, uniform matte film that dries in just one hour. One liter is enough to paint 6 square meters of slate surface. 5. “UNISAL” is a Slovak water-dispersion paint for slate roofs, which is manufactured in Russia by the company “Kvil”, located in the city of Belgorod. During production, the technology of the HELIOS company operating in Slovenia is followed. It is valued for its high degree of hiding power, weather resistance and light resistance. Used for household and industrial painting of slate, as well as other asbestos-cement products. Can be applied by hand or machine. The paint color range includes shades such as: white; brown; grey; oxide red; black; green. The time required for the coating to dry is no more than one hour.
1. Start by applying the first layer, immediately after the primer has dried. As a rule, about two-thirds of the total paint is spent on the first layer, since a clean surface absorbs it very easily.
2. After the first layer of paint has dried, a second layer, the so-called finishing layer, is applied on top of it. The second layer is applied more carefully and carefully. To apply it, you can use a brush or a device for spraying paint - a spray gun.
To paint the roof, a wide brush or broom is suitable, which will allow you to thoroughly rub the paint into all the flaws and cracks of the surface.
Methods for painting slate:
Painting with a brush
This is the simplest method from a technical point of view. But at the same time, it is very difficult to achieve a high-quality, uniform coating with a brush, since painting is done in strokes.
Pneumatic spray painting
It is NOT RECOMMENDED to use such sprayers for painting roofs. This is due to the fact that manufacturers do not recommend diluting the paint by more than 5%.
- painting with a professional airless spray painting machine
Airless spraying is the ideal technology for applying paints in construction and renovation. Using a high-pressure pump (200 atm), paint is supplied through a special hose to the spray gun. In airless spraying technology there is no need to dilute the paint, since such a high pressure is quite enough to apply paint of any viscosity. When painting slate roofing Using airless spraying you can achieve a uniform and uniform coating.
Slate should be painted at a relative air humidity of 60% and a temperature of at least 15 degrees. With high-quality surface preparation and proper application, acrylic paint will last you more than 10 years.
Do-it-yourself painting of slate with your own hands will significantly save your budget for home renovations, since the services of professional craftsmen are not cheap. Having done the painting yourself once, you will learn how to paint slate no worse than experienced craftsmen.
The fact that the use of paints allows slate to achieve the desired color is understandable. But, in addition to the decorative function, coloring compositions also have more important properties. Let us remember that slate is a porous material, prone to the formation of microcracks. Water easily gets into them, which with the onset of winter cold turns into ice and begins to “tear” the fibers of the material. The same deforming processes occur when mosses and lichens grow in the pores. The problem of premature destruction of slate is solved by painting. Coloring compounds form a durable film on its surface, blocking access to asbestos cement to water and microorganisms. As a result, deforming processes are suspended and the slate gains additional years to its service life.
Painted slate, thanks to the paint film, becomes smooth. It does not retain atmospheric moisture and snow melts off easily. And if dirt accumulates on the roof, you can simply wash it off with water from a hose or car wash.
Another problem that can be solved by painting is the theoretical harmfulness of slate. The version that asbestos-cement sheets are not environmentally friendly came to us from the West and is successfully cultivated by many manufacturers of more expensive and modern roofing materials. Its essence is that slate during operation emits asbestos dust, which is harmful to the environment and human health. There is much evidence that this opinion is unfair, however, if this aspect bothers you, paint applied to the slate will completely block the possible release of asbestos dust and will 100% preserve your health.
Thus, staining slate allows you to:
· increase the decorative effect of the roof;
· give asbestos-cement sheets a color with the desired degree of matte (matte, semi-gloss, glossy);
· smooth the surface of the slate;
· protect slate from the growth of mosses and lichens on it;
· prevent the appearance of cracks;
· block the slate dusting process;
· increase the durability of slate by 1.5 times (subject to periodic renewal of the paint layer).
Type #2 - acrylic paints with organic solvents
These paints are not diluted with water, but with organic solvents. Contains: acrylic resin (synthetic latex), color pigments, additives, organic solvent (most often white spirit). The degree of matte finish of such paints depends on the resin content. The more it is, the more pronounced the gloss of the dried film of the composition.
Organic solvent paints are different:
· more durable film than water-dispersed compositions;
· high water-repellent properties;
· elasticity;
· lightfastness and long-lasting color intensity;
· pungent odor.
Solvent-based acrylic paints are presented in a small range on the market. Thanks to its excellent quality, matte paint “Eternit” from Polifarb (Ukraine), produced in red, brown and green, has proven itself among craftsmen. Due to its wear resistance, the color of this paint practically does not change even at the end of its service life. Another popular option is Shikril paint from KrasKo (Russia). It is easy to use and has a high degree of coverage.
Type #3 - organosilicon (silicone) paints
Organosilicon paints are rightfully considered the most reliable and durable for slate. They are suspensions of pigments and fillers in an organosilicon (silicone) binder. Thanks to the presence of silicone, this type paints are characterized by increased elasticity, so some of them are able to bridge cracks up to 2 mm thick!
Properties of silicone paints:
· high strength;
· maximum elasticity, the ability to carry out “repair” work and seal fairly wide cracks in slate using a silicone composition;
· fungicidal and algicidal properties that prevent the proliferation of microorganisms (in the pores and on the surface of slate);
· high water- and dirt-repellent properties;
· the possibility of excluding the priming stage from the painting process;
· silicones are non-toxic, do not have an aggressive odor, and are fireproof;
· service life is 10-15 years.
Repeatedly tested for painting slate, KO-slate enamel, produced by the Kremniypolymer plant (Ukraine). It impregnates the top layer of slate, providing deep, long-lasting color. The company produces “KO-slate” in two colors – red-brown and green, but there is the possibility of custom tinting.
The same Kremnipolymer plant produces enamel OS-5103K (color green), intended for protective and decorative painting of many materials, including asbestos cement. The material has increased heat resistance, acid and alkali resistance, and resistance to chemical gases. Thanks to this, painting slate with OS-5103K enamel can be done at industrial enterprises.
Type #4 - alkyd slate paints
The composition of alkyd slate paints consists of alkyd resins, pigments, fillers in an organic solvent. Alkyd enamels, as a rule, dry quickly and form an elastic film that is not prone to cracking.
Properties of alkyd slate enamels:
· high moisture resistance;
· increased adhesion to slate;
· weather resistance;
· does not require the mandatory use of a primer before painting;
· durability – 5 years.
An example of high-quality alkyd enamel is “Quick-drying enamel for slate” from the company “Impulse” (Ukraine). It is characterized by very fast drying (at 20˚C the layer dries in 1 hour) and has no pungent odor. Available in the most suitable colors for the roof: red, brown, blue and green. Another alkyd-based product is “Roof Enamel” produced by Empils (Russia). In addition to high protective qualities, the paint has a wide tinting base consisting of 10 colors.
Type #5 - polymer paints “Liquid plastic”
They are a suspension of polymers (polyurethane, vinyl or polystyrene), pigments and additives in a solvent. After the composition dries and the solvents evaporate, the paint forms a thin plastic (polymer) layer with a glossy or matte surface on the slate.
Characteristics of “liquid plastic”:
· absolute moisture resistance (completely blocks the access of water to the slate);
chemical inertness
· high drying speed;
· environmental friendliness;
· fire safety (does not burn after drying);
· resistance to fading;
· application without preliminary priming;
· high frost resistance, as well as the possibility of application with small negative temperatures(up to -10˚C);
· durability of the coating – 10-15 years.
Reliable polymer paint Liquid Plastic is produced by Denalt (Canada). This paint is produced on an alkyd-polyurethane base, which gives the composition special strength.
Polymer paint PPG-1 produced by Komoil (Belarus) is another reliable choice. Its composition contains polystyrene, which, after drying, forms a protective and decorative coating of various colors. The paint Ps-160 TM “Sticolor” (Ukraine) also has a polystyrene base. It is a weather-resistant enamel that forms an elastic surface with a glossy effect.
Variety of colors and tinting options
The most popular paint colors for slate are red, brown, and green. They appear in the range of most paints. At the same time, the color base of a particular material can include either 5 or 100 different colors and shades. But what to do if you want to paint the slate, say, light yellow, but the selected paint does not have such a shade in the range? Tinting will come to the rescue. Most paint manufacturers provide the ability to paint their paints in any tone corresponding to color catalogs - RAL, NSC, Symphony. Tinting at the enterprise is carried out using special equipment, using tinting pastes and paints.
You can also do the tinting yourself by adding tinting paste to the purchased paint and stirring the mixture with a mixer.
Slate coloring technology
The choice of paint and its color is a responsible process. But, unfortunately, even the most expensive and high-quality enamel cannot guarantee a reliable decorative and protective coating on slate. If you do not follow the painting technology, then the pigmented film will almost certainly behave unpredictably. For example, it will begin to crack, swell or crumble much earlier than the end of its service life (possibly even a few days after painting). Therefore, you also need to know how to paint slate correctly!
The process of painting slate is carried out in several stages:
Stage #1 - preparing the slate surface
The slate surface to be painted must be cleaned of dust, dirt, fungal and plant deposits, and unstable (or incompatible with the chosen paint) coatings.
Cleaning can be done in two ways: dry mechanical (manual or mechanized) and using pressurized water jets. Sometimes these methods are combined and performed alternately.
For manual mechanical cleaning, wire brushes are used to scrape off efflorescence, dirt, moss and lichens. The work requires considerable effort and accuracy, and the cleaning speed is very low. You can clean slate faster and better with the help of tools. To do this, put an attachment on a grinder or drill, which is essentially the same brush for metal. When the tool is turned on, it begins to rotate, cleaning off surface defects of the slate.
The second cleaning method is to wash the slate with high-pressure water jets, which are created by car mini-washes (Wagner, Karcher, etc.). In this case, the created pressure should be within 100-250 atmospheres. Mini washers that release water at a lower pressure will not be able to remove contaminants, while higher pressure mechanisms will destroy not only the defects, but also the slate itself.
Stage #2 - priming
To impregnate the top layer of slate, special compounds are used - primers. They are selected in accordance with the instructions for using the specific coloring composition. For example, organosilicon paint Ko-slate is combined with silicone primer KO-011S. However, organosilicon paints, as well as “Liquid Plastic” compositions and alkyd enamels can be applied without prior priming. Acrylic paints, on the contrary, require the use of a primer. These can be either special compositions (for example, Dupa-grund for Alpina DACHFARBE) or paint diluted according to the instructions. To obtain an impregnating primer for Alpina DACHFARBE acrylic paint, it is enough to dilute it with water to 10% of the volume.
The primer is applied to the slate in 1-2 layers using a brush, roller or spray gun.
Stage #3 - painting itself
Direct painting is done over the dried primer. As a rule, it is enough to apply 2 layers of paint, the first of which will be the base, and the second – the finishing. The base layer is the main one; it must carefully cover the entire surface of the asbestos cement, including the ends, corners, joints, ridge and corner parts. After the first layer has dried, paint it again. The task of the second (finishing) layer is to ensure that the painted slate receives a bright, uniform color, without streaks.
Treatment is carried out with a brush, roller or spray.
This simple technology will give slate color and high decorativeness, comparable to the beauty of tiles, bitumen or metal roofing. In addition, painting (with periodic renewal of paint) will provide reliable protection for the roof from exposure to environment and will increase its service life by decades.
And this type of sprayer requires highly diluted paint.
In the domestic construction market, slate has remained one of the most popular materials for many years. Today it is used both unpainted (for country houses, for outbuildings and non-residential premises) and in painted form. The latter option can give the house additional aesthetics. However, if you decide to transform the roof of your house, you should choose the right materials. Let's try to figure out how to paint slate, which paint is preferable and why?
Let's start with the fact that most of our compatriots are firmly convinced that only wavy sheets are “slate”, but in fact, flat sheets made of asbestos-cement chips also fall under this definition.
The modern choice of materials is huge, and this makes it possible to make the roof of a house truly individual. When choosing what to paint slate with, evaluate all the advantages and disadvantages of imported and domestic options and only then make a purchase.
The list of undeniable advantages of acrylic or water-dispersed compositions includes:
If you are looking for how to paint flat slate? Acrylic paint is best suited for these purposes. It provides the roof with maximum resistance to weathering and temperature changes.
This option contains a binder that promotes the formation of a smooth film on the roof surface. A roof painted with such enamel is not only durable, but also has high water-repellent properties and is reliably protected from the destructive effects of ultraviolet rays.
This synthetic composition is made on a polystyrene, bitumen or vinyl chloride base. The high popularity of this paint for slate is explained by the ease of its application, as well as its high elasticity, which eliminates the risk of delamination of the coating. Rubber paint contains pigments that prevent the color from losing its brightness for a long time. The only drawback is toxicity. The composition should be applied wearing special respiratory and hand protection.
If an already installed roof is to be treated, preparatory measures will be required. To do this, you should prepare a brush with metal hairs, an angle grinder or a drill with a special brush attachment, or a high-pressure car wash. The latter option will make the process less labor-intensive and highly efficient.
Using the above tools, we clean the roof from plaque, moss, etc. Next, we treat the surface with an antiseptic, which will prevent the proliferation of fungi and the appearance of plaque. The next stage is primer.
By carefully priming the slate sheets, you can be sure of maximum adhesion of the paint to the surface of the roofing material. In addition, the primer, by filling the pores, will significantly save the paint itself, and the roof surface will become more even.
It is best to paint the surface in 2 layers. The composition can be applied using a roller or brush or spray. It is not recommended to paint slate in rainy weather or very hot days.
