What kind of waterproofing can be applied to gypsum plaster. Is it possible to apply plaster to waterproofing? The procedure for carrying out plastering work
The choice of plaster is an age-old question that citizens face when carrying out repairs, but not about choice will do speech in this article. In our case, preference was already given to gypsum plaster, but it so happened that the owners wanted to lay tiles on such a base. Is it possible or not? The opinions here are diametrically opposed, let's try to understand the problem.
The essence of the dilemma
Gypsum plaster is elastic, does not contain large sand grains, like cement-sand plaster, so it can be used to create a coating close to the finish. This base is well suited for painting or wallpapering. Plaster has a pleasant white color and dries quickly. At the same time, it is believed that such a coating is not very suitable for tiles and there are reasons for this:
- High hygroscopicity is a mysterious word that often arises in discussions related to gypsum. Hygroscopicity means the ability of a material to absorb water. In a humid environment, gypsum plaster can absorb the smallest particles of water, as a result of which it loses strength, and pathogenic flora (fungi and mold) can develop inside.
- Low strength - everyone who has dealt with gypsum knows that the material does not tolerate mechanical damage well. For this reason, heavy tiles should be laid on gypsum plaster with great care.
Gypsum plaster does not have a grainy texture, so it gives the walls a finished appearance.
- Promotes corrosion - this disadvantage of gypsum does not apply to tiles, but to metal fasteners in general, on which the material has a destructive effect.
How to prepare gypsum plaster for tiles?
To the question whether it is possible to glue on gypsum plaster ceramic tiles You can give a positive answer, but with certain reservations.
Tile adhesive is applied thin layer so as not to create unnecessary load.
- The layer of plaster should be twice the thickness of the tile together with tile adhesive.
- Do not use tile adhesive to correct uneven plaster. Because of this, the thickness of the glue and the weight of the finishing coating, which is already significant, increase. For leveling, it is best to use gypsum plaster and wait for it to dry. Protrusions on the old coating must be ground off.
Grouting mesh is used to correct minor unevenness.
- The tiles should be as light as possible; it is not recommended to use heavy varieties made of stone or marble.
- Antiseptic treatment is an important step in preparing a room, especially if we are talking about a wet room (bathroom, toilet or shower). The compounds are applied to the surface and protect the plaster from mold growth.
A heat gun can help dry damp areas.
When working in the bathroom, it is recommended to pre-dry the room. To do this, you can use a heat gun.
Primer is a mandatory procedure to strengthen the gypsum base.
- The primer partially corrects the shortcomings of gypsum plaster, so this procedure should not be neglected. Compositions are suitable for this deep penetration, which impregnate the base, improve the adhesion of the plaster with the finishing coat, and increase waterproofing properties material, protect the gypsum from subsequent shedding under the weight of the tiles.
- The waterproofing used is not simple, but special, which is designed for laying tiles. Mastic and latex coating compounds are used as waterproofing. When applying the composition, you must follow the manufacturer's recommendations. Some waterproofing is applied in two layers.
Mastic waterproofing layers may have different colors to immediately notice unpainted areas
Waterproofing is applied to the junctions of the walls and the floor, and waterproofing tapes are also laid in these places. These tapes are glued at the junctions with pipes and other communications.
- If it was not possible to abandon heavy tiles, then the surface must additionally be covered with reinforcing mesh. As stated, gypsum promotes rust, so it is recommended to use plastic mesh.
Installing tiles on a gypsum base is practically no different from laying tiles on cement-sand plaster.
- Before starting work, markings are made. The approximate location of the tiles can be marked on paper and then on the wall. At this stage, you can install beacons. Do not forget about the presence of seams between the tiles. To mark straight horizontal and vertical lines, you can use a plumb line and level.
Marking the lighthouse under the tiles.
Marking can be done conveniently using laser level or beating threads.
- When calculating the height of the tiles, do not leave the halves to join the ceiling, this will spoil the appearance of the room.
- When choosing tile adhesive, it is important to choose a composition based on gypsum binder. The glue must have an elastic consistency and provide good adhesion. Avoid using cementitious compounds as the tiles may collapse in the future.
Mixing tile adhesive using a mixer.
- The glue is applied to the wall in a small layer. If you also apply the solution to the tile itself, the weight of the finishing coating will increase, and this is fraught with consequences. To minimize the thickness of the adhesive layer, use a notched trowel to make furrows.
- You should not put any stress on gypsum plaster, so all procedures for sawing or drilling tiles should be done before fixing them to the wall. The tiles are mounted on the wall according to the markings. After completing the work, the surface should be washed from any glue residue.
A few words about the bathroom
Despite all the bold recommendations from manufacturers of various building mixtures It is better to refrain from using gypsum plaster in bathrooms and other wet areas. It is only worthwhile to apply gypsum compositions to the ceiling before painting, since such a coating will be lighter than cement plaster, and at the same time it will have a smooth, pleasant surface.
Conclusion
Thus, we can conclude that it is possible to lay tiles on gypsum plaster, but only this must be done while observing all the preliminary procedures for preparing the base. Still, more natural finishing options for gypsum compositions are paint or wallpaper.
Waterproofing plaster mortars consist of mineral binders (usually cement), fillers and polymer and mineral additives. Designed for making insulating layers in basements, foundations, bathrooms, showers and other wet rooms, in swimming pools, wells, pipes, on roofs, balconies, etc.
They are used on external and internal surfaces, on walls and floors on dense concrete, cement plaster, brickwork all types with filled joints (masonry with voids in the joints must be pre-plastered with a layer of at least 10 mm). Provide water resistance while maintaining vapor permeability. Supplied in the form of dry mixtures. Elastic mixtures can be applied to stressed foundations (for example, reinforced concrete structures), where there is a possibility of cracks opening.
A general requirement for the use of solutions is the preparation of the base. Solutions must be applied to strong substrates that are free of dust, dirt, lime, oils, fats, and paint residues. Sinks and recesses must be level cement mortar.
The dry mixture is mixed with water strictly according to the recipe and mixed thoroughly. It is recommended to use a mixer. Application temperature – from +5 to +30 degrees. C. During the hardening process, the coating must be protected from drying out (wind, sun), freezing, rain, work load. The applied layer should be protected from damage (plaster, screed or other means). Store the mixtures in the original packaging, preventing the liquid components from freezing.
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
"Gidrolast"
Domestic analogue Barralastic, a thin-layer universal waterproofing coating based on cement and special polymers of the latest generation. It is used when the water column pressure is up to 3 m. The coating is vapor permeable and elastic enough for low-deformable bases. It has high adhesion to any surface (more than 0.9 MPa), forms common crystals with mineral bases, and is frost-resistant (more than 200 cycles). Apply with a brush in two layers with a total consumption of 2 kg/sq.m. m. Supplied in 15 kg bags + 3 liter canister.
GR-1 mixture "Alit"
(TU 5745-002-45498032)
Mortar for plastering waterproofing works. Developed by the St. Petersburg University of Transport. Supplied by JSC "Vasko" in 25 kg polyethylene bags.
Application
Stir twice for 10-15 minutes to allow swelling. Apply to walls using plaster technology in 2-3 layers of 4 mm with a break of 24 hours, on horizontal surfaces - as a 15-20 mm screed with vibration compaction and smoothing or manually in two layers. The formation of shrinkage cracks should be prevented through the use of special means. Before applying a new layer, it is recommended to treat the surface wire brush.
Atlas Woder S
The waterproof solution can withstand water pressure up to 5 meters. It is a mixture of cements, powder resin, mineral additives and modifiers. It is characterized by good adhesion, water and frost resistance, low elasticity, manufacturability and low shrinkage. Supplied in 25 kg bags. Shelf life – 6 months.
Application
Apply the mixture to the base in at least 2 layers (the first layer is with a brush). Can be applied to freshly finished surfaces (eg plastered) after 14 days. The mixture hardens within 3 days.
"Addiment Barralastic"
(Manufactured by Heidelberger Zement, Germany)
Two-component waterproofing mortar (cement-based dry mixture plus binding emulsion). When hardened, it forms common crystals with cement. Thanks to its high adhesion, it can be used on almost any material - concrete, brick, metal, wood. Withstands lifting pressure up to 4 atm and pressing pressure up to 9 atm (40–90 m of water column). Resistant to acids, alkalis, petroleum products, etc., environmentally friendly, non-toxic, highly breathable, has a hygienic certificate, can be used in food water supply systems. Elastic, tolerates temperature changes, vibrations, movements, and frost. It has a density of about 1.3 kg/l. Shelf life 1 year.
Application
Mix thoroughly, use after 10 minutes, apply with a brush or spatula in two layers of 1 mm each. Drying time – 1–2 hours, complete hardening – after 1–2 days. Does not require sealing cracks smaller than 1 mm.
Waterproofing mixture
(Produced by Bauta, Germany)
Elastic mixture based on polymers for insulating concrete, masonry, cement plaster and self-leveling floors for interior and exterior work with a water pressure of up to 5 meters. Depending on the pressure, consumption is 4–10 kg/sq.m. m. Shelf life – 1 year.
Application
Mix with a mixer, apply with a spatula in a layer of about 3 mm, after a while treat the surface with a damp brush. Use the mixture within 1 hour. Protect from external influences for 1 day, ready after 5 days.
"Osmoflex"
Two-component plastic coating made of binders, fillers and styrene-butadiene resins. It is used for insulating structures, including those subject to vibration and dynamic loads, as well as for creating a flexible connection between walls and floors, ceilings, pipes and masonry, etc. Withstands crack opening up to 1 mm without compromising the waterproofing. It has good adhesion to various materials, is non-toxic, frost-resistant, protects against carbon and sulfur oxides, chlorides and sulfides.
Application
Apply a layer of up to 2 mm with a sprayer or spatula. If necessary, reinforce the coating with fiberglass mesh with 4x5 mm cells. Do not use in frost below -5 degrees. With and under pull-out pressure; do not apply a layer thicker than 2 mm.
"Covercol"
(Produced by Index S.p.A., Italy)
A universal two-component waterproofing and adhesive elastic composition made of acrylic elastomers and astringent additives. It is used both for waterproofing and for gluing tiles, stones and mosaics in swimming pools and showers, on floors that require waterproofing. It is characterized by increased adhesion, frost resistance and resistance to aggressive environments. Consumption for waterproofing – 1.5–2 kg/sq.m. m, when used as an adhesive solution - 2–3 kg/sq. m. Packaging – 20 kg buckets. Shelf life – 1 year.
Application
Apply with a spatula on a damp surface in a layer of 1.5–2 mm. In areas with defects or subject to cracking and dynamic loads "Covercol" it is necessary to reinforce it with reinforcing fiberglass mesh with 3x3 mm cells, recessing it into this layer. After the composition has hardened for 4 hours, you can begin facing work using the same "Covercol". It is not recommended to walk on the "Covercoat" layer before laying the facing materials.
Ceresit CR-65
Cement mortar for internal and external waterproofing of non-deformable mineral substrates. Shrink-proof, vapor-permeable, frost-resistant. Brick and concrete surfaces can be insulated no earlier than 3 months from the date of installation, plaster and cement floors - after 28 days. Dissimilar substrates (brick/concrete, for example) must first be plastered. External and internal corners the bases must be rounded. Use the solution within 2 hours. The first layer is applied with a brush, the second with a spatula, “wet on wet”. Protect from exposure external environment 1 day, ready in 2 days. Supplied in 25 kg bags. Shelf life – 1 year.
Ceresit CR-66/CR-166
Elastic two-component cement-polymer waterproofing for deformable bases. Frost-resistant, bridging cracks up to 0.5 mm, suitable for interior and exterior use, vapor permeable, environmentally friendly. The coatings can be applied to plaster, tiles, and floors. Do not apply to gypsum or anhydrite substrates or substrates with salt deposits. On expansion joints and opening cracks should be used sealing tape or sealant. Storage – 1 year. Supplied in bags and cans: CR-166– 24 kg and 10 l; CR-66– 23.4 kg and 6.66 l.
Application
Stir twice for 5 minutes. Apply on a damp base, without puddles. External and internal corners of the base must be rounded. Apply the coating in 2-3 passes with a brush, “wet on wet”, after 3 hours. Resistance to precipitation – after 24 hours, complete readiness – after 3 days.
Epasit DS, DSS
Coating waterproofing. This mineral solution can serve as a base for floors, plasters (except gypsum), cladding slabs and panels, the inner layer for swimming pools and water storage facilities. Hardens without shrinkage and cracks, has high wear resistance. Difference DSS– increased sulfate resistance. Waterproof at 1.5 bar (15 m water column). Supplied in 30 kg bags.
Application
Apply with a brush, spray, or spray on moistened substrates at a temperature not lower than +5 degrees. C. Apply at least two layers with a total thickness of 2–5 mm. Use the solution within 2 hours.
Epasit DSF/2K
(Produced by EPASIT GmbH Spezialbaustoffe, Germany)
Elastic waterproofing (capable of stretching up to 34%). It is a two-component composition - a dry mixture D.S. and a liquid component for mixing. Can be used to seal joints in porous concrete. Remains waterproof under a water pressure of 15 meters. Apply a layer 2–5 mm thick. Use within 1 hour. Supplied in 30 kg bags plus 12 liter canister.
|
||||||||||
"Dichtungsschlamme"
(Produced by "TIGI Knauf")
Cement waterproofing mineral mortar. It is always applied from the water pressure side with a layer of 2–4.5 mm (3.0–7.0 kg/sq. m) depending on the pressure. Supplied in 25 kg bags.
Application
Stir twice and leave for 5-10 minutes to swell. Apply 2–3 layers with a brush or spatula using the “wet on wet” method. Leave in a well-moistened state for 24 hours. Complete hardening after 5–7 days.
The main purpose of plaster mixtures is to prepare the base for finishing, that is, in rough leveling and surface hardening. But there are also plasters that, in addition to their main functions, perform other tasks: increase heat and sound insulation, protect against harmful radiation, give the base fire-resistant properties, and so on. They are called compounds special purpose, and is used taking into account functional features these solutions.
Special types also include waterproofing plaster, which is used for finishing surfaces exposed to increased moisture. First of all, these are foundations, ground floors, basements, and outer walls of houses located in damp areas.
How does this plaster differ from ordinary plaster, and how should it be applied correctly?
Waterproofing mixtures form a dense hard surface, preventing moisture from penetrating into the thickness of the walls or foundation. They are applied manually and by machine and are used both outdoors and indoors. Depending on the composition of the components, waterproofing plasters are divided into 2 types:
- cement-sand;
- asphalt.
The first type is more common and is widely used in private construction. Cement-sand You can make plasters yourself, and the process of applying them is almost no different from conventional plastering.
To prepare the solution, cement grade M400 and higher is used, and the filler is fine quartz sand, stone flour, finely ground coal, bitumen additives. To increase water resistance, liquid glass, ceresite, sodium aluminate and other water repellents are added to the solution.
The ratio of binder and filler is usually 1:2, less often 1:3. For maximum efficiency, the coating thickness should be 25 mm, provided that the plaster is applied from the water pressure side. Application is carried out in several layers, minimum thickness– 3 mm. This type of waterproofing has many advantages:
- high reliability even with prolonged flooding of the foundation and walls of the house;
- resistance to repeated freezing;
- environmental safety - the plaster composition can be used to finish the internal surfaces of drinking water tanks;
- plaster serves as an excellent base for painting and cladding;
- has good adhesion;
- low cost of the solution;
- resistance to mechanical damage.
In order for the coating to be of high quality and durable, it can only be applied to a carefully prepared base. In addition, the surface must be strong and not prone to shrinkage, otherwise the plaster will become covered with cracks. For work, it is preferable to choose factory mixtures with clearly defined proportions of components. They are available in dry form, and to prepare the solution it is enough to mix the powder with water in the required ratio.
Asphalt plaster used primarily in industrial facilities. Its cost is quite high, and special equipment is required for application, so in private construction the use of such waterproofing is not always justified. The plaster contains petroleum bitumen, asbestos dust, sand and mineral fillers in powder form.
There are two ways to apply asphalt plaster - cold and hot. The cold solution is applied manually or by machine, and it is much easier to work with. The second method involves heating the solution to 180 degrees and applying it using special equipment. In this case, the waterproofing is as reliable and durable as possible.
Popular brands cement-sand plaster for waterproofing
| Name | Brief characteristics |
|---|---|
| The mixture forms a hard, waterproof coating with good vapor permeability. It has excellent frost resistance (up to 200 cycles), resistance to alkali and salt exposure. Designed for waterproofing external and internal vertical surfaces that are not prone to deformation and shrinkage, and are not subject to vibration. It is used for finishing buried structures, water tanks, swimming pools, and for filling voids in old brickwork. Available in the form of dry powder, packaged in 5 and 25 kg |
| Elastic mixture on a cement-polymer basis. Designed for deformable and shrinkage-prone substrates. Suitable for all mineral surfaces that do not contain gypsum. Used to protect buried structures, walls and foundations of houses located on the shores of reservoirs, finishing swimming pools and tanks for household purposes. The composition has increased resistance to chemically aggressive substances - alkalis, acids, acetone, hydraulic oil and others. Standard packaging contains a canister of emulsion (10 l) and a bag of dry plaster mixture (25 kg) |
| Two-component elastic mixture of deep penetration. Designed for waterproofing all types of surfaces, including those subject to vibrations and shrinkage deformations. It has very high adhesion, after drying it forms an absolutely waterproof coating, but with vapor permeability. The solution has good plasticity and is easy to apply with a brush or spatula. The standard kit includes a bag of dry mixture (25 kg) and a canister of emulsion (5 l) |
| A cement mixture with active additives intended for waterproofing concrete surfaces. The solution penetrates 40-50 cm into the concrete, completely closing the pores of the material, resulting in the surface becoming completely moisture-proof. The composition is used for finishing foundations and plinths, basements, cellars, wells, and swimming pools. When applied to brick or masonry, wood, foam concrete and other materials, the waterproofing effect of the coating is absent. The composition is environmentally safe, frost-resistant, resistant to alkalis and acids. Packaged in plastic buckets with a capacity of 5, 10, 25 kg |
| Dry cement mixture of penetrating type for concrete bases. It is a more budget-friendly analogue of Penetron, which is why it is in good demand. Apply with a brush or spray in two layers. It is resistant to chemically aggressive substances and temperature changes. Packaged in plastic buckets of 10 and 25 kg |
The average consumption of ordinary waterproofing plaster is 1.5 kg per m2 when applied in a single layer. The consumption of penetrating compounds is less - about 0.4-0.6 kg/m2. Of course, this indicator directly depends on the quality of the surface, the method of application and the thickness of the layers, so before purchasing the material you should carefully calculate everything and add 10-15% of the calculated amount of the mixture in reserve.
Prices for waterproofing plasters
Waterproofing plasters
Conditions for applying plaster
Waterproofing plaster solutions cannot be applied to crumbling, loose substrates, coatings containing gypsum, as well as surfaces with efflorescence, traces of bitumen, paint, or oil stains. All this reduces adhesion, which means the plaster will not last long. It is also unacceptable to plaster bases with cracks whose width exceeds 0.5 mm.
Such a wall cannot be plastered without prior repairs.
To properly prepare the surface, you need to completely remove layers of paint, old plaster or putty. If the paint is difficult to remove, it is advisable to soften it by heating it with a hairdryer or special chemical removers. After this, it can be easily removed with a spatula. Plaster and putty are cleaned with a metal brush; you can also use a grinder with an attachment. Excellent result sandblasting gives.
The seams of brick and stone masonry must be cleaned with a wire brush and removed from dust. If the masonry is old and the seams are crumbling, they are cleaned to a solid base and then filled with fresh cement mortar. Before sealing, cracks must be opened to a depth of 1-2 cm and cleaned of dust.
When finishing surfaces with a heterogeneous structure (concrete and brick, brick and stone), the base is first plastered with a regular cement-sand mixture.
Like regular plaster, the waterproofing layer needs reinforcement if its thickness exceeds 10 mm. When plastering rough masonry or a surface with numerous defects, when the solution is applied in a thick layer, a galvanized metal mesh with cells from 10x10 mm to 20x20 mm is used for reinforcement.
It is fixed to the base using plastic dowels and screws with a fastening pitch of 40-50 cm.
It should be used on a flat surface, provided that the layer thickness does not exceed 30 mm.
At least 3 months must pass between the construction of the masonry and its waterproofing. This also applies to concrete foundations. If preliminary leveling is carried out with ordinary cement mortar, waterproofing plaster can be applied no earlier than after 28 days. Plastering should be done in dry, windless weather, at a temperature not lower than +5 and not higher than +30 degrees. Optimal humidity air – 60%. Moreover, such conditions must be observed not only during the period of applying plaster, but also for several days after completion of the work.
Prices for plaster mesh
Plaster mesh
Plastering is done manually or by machine. The first option is much more practical, since it does not require equipment and the solution consumption is less. True, it takes more time to work, and the reliability of adhesion to the base is slightly lower. Mechanical method allows you to do everything much faster and without much physical effort; moreover, with this application, the solution adheres very firmly to the surface, and the coating acquires high strength. The disadvantages include high consumption of the working mixture and the need for a special installation.
Manual application method
To work you will need:
- kneading container;
- construction mixer;
- metal spatula;
- paint brush with semi-rigid bristles;
- pure water.
Step 1. The prepared surface is slightly moistened with water using a wide brush. The base should be moist, but not wet, especially since puddles are not allowed on horizontal planes.
Step 2. Pour into the container clean water room temperature, add the dry mixture and stir with a mixer at a speed of 400-800 rpm for 3 minutes. The proportions of water and dry mixture are indicated on the packaging. If it is a two-component composition, first pour the emulsion into the container, add water (if indicated in the instructions), stir and only then add the dry ingredients. For the first layer, the solution is made more liquid: on average, take 1 part water for 2.5 parts of the dry mixture. After mixing, leave the solution for 5 minutes to mature, then mix again with a mixer.
Construction mixer price
Construction mixer
Step 3. The first layer is applied with a brush, making movements in one direction. The solution is taken little by little and thoroughly rubbed over the surface, paying special attention to the joints. Make sure that the layer remains uniform over the entire area, avoid the formation of sagging and drips. It is not recommended to return to already treated areas to correct something; this violates the integrity of the layer and reduces the adhesion of the material to the base.
Step 4. After completing the application of the plaster, you must wait until it begins to harden. After this, prepare the next portion of the solution, but this time add less water: approximately 1 part water to 3 parts dry mixture.
Step 5. It is better to use a spatula to apply the second layer. Recruiting in small portions solution and evenly distribute it over the base in a thin layer from bottom to top, holding the spatula at an angle to the surface. Movements with a spatula must be performed in a direction perpendicular to the direction of the brush. That is, if you applied the first layer with vertical movements, then the second should be applied horizontally. If a third layer is necessary, this rule must also be followed.
Step 6. The plastered surface must be protected from drying out, mechanical loads, direct sun rays. If the weather is too warm, the plaster must be periodically moistened with water using a sprayer. After 7 days, when the coating is sufficiently strong, the plaster is grouted. To do this, make a liquid solution, spread it in a thin layer on the surface and smooth it in a circular motion using a polyurethane or metal grater.
Immediately after plastering, the coating cannot be rubbed down, as this will disrupt its density and adhesion to the base. Finishing work can be continued after 3-7 days, depending on the composition of the plaster. For example, a Barralastik coating can be tiled within 20 hours after applying the last layer, for Ceresit CR 65 it takes 3 days, for Penetron - from 7 to 14 days.
Mechanical method of application
Mechanical application, or shotcrete, is carried out using a special installation with a compressor and nozzle. Before shotcrete, a smooth concrete base is sandblasted or small notches are made manually over the entire area.
On bases with a rough, uneven surface, a reinforcing mesh made of galvanized metal is pre-fixed.
Step 1. The working surface is slightly moistened.
Water is poured into the installation container and the dry mixture is poured in the proportions specified by the manufacturer. Set the pressure within 0.25...0.3 mPa, check the supply of the solution on a separate section of the wall. If the mixture begins to float or slide down, it means that there is excess water in the solution, and dry components should be added, but if dry spots form on the plaster layer, you need to add water.
Step 2. To apply the solution evenly, hold the nozzle perpendicular to the wall at a distance of 80-100 cm from the surface, slowly moving it in a circular motion. The thickness of one layer should be within 7-10 mm. Having completed the work, cover the plaster plastic film to protect from drying out.
Advice. If you need to take a forced break in work, the edge of the plaster on the already treated area is cut at an angle of 45 degrees and scratched with a metal brush over the fresh mortar. After resuming the work process, the cut area must be moistened generously with water.
Step 3. The next layer is applied one day after the first, and the same interval is maintained before applying the third layer. The total thickness of the coating should not exceed 50 mm.
Step 4. After the plaster has hardened, a liquid solution is prepared, manually applied to the coating and grouted with a metal or polyurethane float. Next, cover the surface with polyethylene or periodically moisten it with water to avoid cracking.
For 7 days, the plaster must be protected from freezing, direct sunlight, and mechanical stress. If everything is done correctly, the coating after drying has an even color, a smooth hard surface, and makes ringing sounds when tapped with a wooden hammer.
Video – Robot plasterer PlasteRUS SPERO
Video - Waterproofing plaster
Special waterproofing plaster is used in the construction of buildings to protect risk areas from moisture. When building a private house protective composition used for treating basements, attics and foundations. In damp climates, hydroplaster is used to cover the outer walls of multi-story buildings and basement floors. The waterproofing mixture is used separately or in combination with insulation. For application, manual or machine methods are used. After hardening and hardening, the waterproofing mixture forms a coating of high hardness. Moisture does not penetrate into the structure of a foundation or wall with a dense waterproof coating.
The waterproofing solution is prepared from M400 cement with fillers (bitumen, coal powder, fine-grained quartz sand, stone flour). Plaster composition to enhance water resistance, it is supplemented with water repellents such as sodium aluminate, ceresite, liquid glass and other components.
The filler and binder in the dry composition are mixed in proportions of 2:1 or 3:1. For waterproofing, two types of plasters are used: asphalt and cement-sand. The second type is widespread in private housing construction; such mixtures are easily made independently.
Waterproofing plaster: brands and manufacturers
Construction stores offer a wide range of ready-made waterproofing materials. The mixtures are sold in 25 kg multilayer kraft paper bags, 25 kg polyethylene bags, 20 kg buckets, 15 kg bags, complete with a 3 liter canister of emulsion. In terms of price, properties and universal purpose, the following brands stand out favorably:
Consolit 540;
Hydrolast;
Osmoflex;
Covercol;
Dichtugsschlemme.
Magma– cement mixture with mineral additives for underground passages, elevator shafts, showers, swimming pools, basements and foundations. It is applied to brick, concrete, cement-sand, reinforced concrete bases and provides rigid waterproofing. This plaster is not suitable for surfaces made of wood, asbestos cement and gypsum, with cracks and salt deposits, or for painted walls.
The mixture cannot be used if the surface:
- deformed under the influence of changes in high and low temperatures or shrinkage;
- experiences high mechanical loads;
- covered with fresh concrete (less than 3 months).
Also the composition is not suitable for coating cement screeds with a curing period of less than 28 days.
Consolit 540– hydro plaster for saunas, basements, laundries, swimming pools (walls and ceilings), foundations. The mixture has high strength, corrosion resistance, and reinforcing properties building structures. The composition contains a protective modifier against microcracks. Plaster is effective in restoration work.
Hydrolast– a cement-polymer mixture for applying a thin-layer coating, used on surfaces exposed to a column of water up to three meters. Properties: vapor permeability, elasticity, frost resistance, high adhesion. Upon contact with a mineral base, it forms general crystalline structures.
Barralastic(pictured below) is a two-component dry mixture for coating wood, metal, brick and concrete. Plaster waterproofing is highly breathable, resistant to alkalis, petroleum products and acids, environmentally friendly and non-toxic (this is confirmed by an environmental certificate). The composition is suitable for treating food water supply systems. Advantages - elasticity, resistance to frost, vibration, movement and temperature changes, pull-off pressure of 4 atm. and pressure 9 atm.
Bauta– a mixture of elastic structure for external and interior work. The material is used for arranging self-leveling floors and waterproofing cement plasters and concrete masonry. The composition is effective under conditions of water pressure up to 5 m.
Osmoflex– plastic composition with butadiene-styrene resins for flexible connections between walls and pipes, ceilings and floors, for structures with dynamic loads and vibrations. It has high adhesion, resistance to frost, exposure to sulfides, chlorides, oxides of sulfur and carbon.
Coverkol– a universal waterproofing-adhesive mixture of two components: a binder and an acrylic elastomer. The material is used for waterproofing and gluing cladding (mosaics, stones, tiles) in rooms with high humidity. The carpet is designed for waterproofing walls and floors in bathrooms, showers, and swimming pools; it is resistant to aggressive substances and low temperatures. Distinctive feature– high adhesion.
Dichtugsschlemme– a cement-mineral based mixture for application on the water pressure side in a layer of up to 4.5 mm. Manufacturer: Knauf TIGES.
How is plastering waterproofing of walls carried out?
The waterproofing layer on the water pressure side is applied with a thickness of 25 mm. This gives effective protection during a period of prolonged exposure to water on walls and foundations. The coating is stable during periods of spring flooding and can withstand winter freezing of the soil. Tanks with drinking water coated with environmentally friendly compounds, special adhesives are used as a base for cladding and painting. Processing technology – application of material in several layers with a thickness of 3 mm.
Important! Do not apply the solution to loose or crumbling masonry, gypsum surfaces, walls with a tendency to shrink. If cracks more than 0.5 cm wide or salt deposits have formed on the base, plastering cannot be done. Choose high-quality mixtures of proven brands, strictly observe the proportions, follow the manufacturer’s instructions.
Waterproofing plasters are applied to carefully prepared substrates. Preparation includes three mandatory stages:
Remove old putty, plaster and paint. Use a grinder with an attachment or a wire brush, hammer, chisel or chisel. If you have difficulty removing paint, soften the coating chemical preparation or by heating with a special hairdryer. To obtain a clean and even surface on large area use a sandblaster.
Sand the joints in stone or brickwork to a solid surface. Treat deep recesses in old walls with leaking seams with a wire brush, remove dust, and fill with cement mortar. Clean the cracks from dust, open them one or two centimeters and putty.
Reinforce the surface if the thickness of the waterproofing layer exceeds 1 cm. Thick layers are applied to damaged bases and rough masonry. Use galvanized metal mesh with a cell size of ten by ten or twenty by twenty millimeters. Secure the network with self-tapping screws with wide washers. If you apply a layer of waterproofing thinner than 30 mm on a flat base, use fiberglass reinforcing mesh.
Important! On walls made of dissimilar materials (brick+concrete, brick+stone), cement-sand is first applied plaster mixture, and then the plastered wall is waterproofed. 28 days must pass between these stages. Fresh masonry can be processed no earlier than after 3 months. Temperature and humidity conditions: from +5 to +30 degrees, 60% humidity, dry, windless weather.
After preparation, apply the plaster by hand or machine. Manual waterproofing is a lengthy process, but economical in terms of mixture consumption. Machine plastering is a quick method that guarantees strong adhesion of the mortar to the surface. But mechanical application consumes more solution and requires the use of special equipment.
Manual waterproofing of plastered walls
Instructions for applying waterproofing plaster with your own hands:
Lightly moisten the finished cleaned surface with water. To do this, use a wide brush. Make sure that the wall is damp, but not too wet, and that puddles do not form on the floor.
Pour water into a bucket, add the dry mixture, stir with a mixer for three minutes at 400-800 rpm. The volumes and ratio of water and dry matter are indicated in the manufacturer's instructions on the packaging. Two-component formulations are diluted in stages: first, water is added to the emulsion, then the dry substance.
Apply the first layer of waterproofing (semi-liquid, in a ratio of 2:1). Apply the solution with a brush using movements in one direction, thoroughly rubbing the mixture over the surface. For one application, take a little solution, carefully coat the seams and joints, smooth out drips and sagging. Do not return to the treated fragments for corrections: this will lead to reduced adhesion and destruction of the integral structure of the insulating layer.
Wait until hardening begins, prepare a second batch (thicker, in a ratio of 3:1). Apply the second layer with a spatula using upward movements. Hold the tool at an angle, make the layer thin and even. The direction of movement is perpendicular to the movements of the brush when applying the first layer. Apply the third layer in the same order, again observing the perpendicularity condition.
Expect complete hardening within a week. In hot weather, periodically moisten the plaster with a spray bottle to protect it from sunlight and drying out.
After 7 days, grout with a liquid solution: pour onto the surface and smooth with circular movements. Use a metal or polyurethane grater.
Important! If you had to stop and postpone work on applying waterproofing for a while, decorate the edge with a cut corner of 45 degrees. Scratch the oblique cut with a wire brush. When work resumes, wet the area with water and wait a day before applying the next coat.
Video
The video in this article clearly shows how to apply Anserglob waterproofing mixture.
The operational life of construction projects depends on many factors. Excess moisture has a significant impact on the condition of the building. Anyone can protect the walls of a house from moisture, which leads to destruction, with their own hands. And about the most effective way to protect your home from excess humidity we will tell you in this article.
Types of waterproofing plasters and their features
Plaster waterproofing is the optimal solution. It can prevent moisture from penetrating into the thickness load-bearing walls. This finishing can be used on low-rise residential construction projects. At the same time, with the same success - and on large buildings public type. ().
On this moment Two types of waterproofing finishing materials are widely used:
- asphalt plaster;
- cement-sand plaster.
Cement-sand waterproofing mortars
Waterproofing plaster based on cement and sand is durable coating. It is resistant to negative impact environmental factors. Unlike conventional cement-sand coatings, waterproofing finishes have a high density. It is also characterized by an extremely small number of pores in the thickness of the finishing layer.
A cement-sand waterproofing solution is prepared by mixing non-shrink Portland cement, washed river or quarry sand and water. All of the above components are used subject to certain dosages. This is done to achieve optimal performance of the plaster mixture.
The most popular mixtures are waterproofing cement-sand mortars. But only those produced with the addition of ferric chloride. (In proportions 1:16, 1:22, 1:26 relative to the mass of cement.)
This type of plaster mortar is characterized by short setting times. This occurs due to the addition of sulfate-yeast mash in an amount of 0.2% of the total mass of the material. In order to prevent the possibility of unauthorized setting, the solution is stored in hermetically sealed polyethylene containers.
To treat plinths and buried structures, solutions with ferric chloride additives can be used. This plaster is advantageous due to its increased degree of hydrophobicity.
Cement-colloidal plaster mortar is prepared in special mixers using dry, finely ground sand and cement. Water with sulfate-alcohol mash is added to the prepared mixture. Such modifications of plaster are suitable for finishing structures that are not subject to uneven shrinkage. (Whose foundation is laid on solid ground.)
Application of cement-sand waterproofing
Cement-sand waterproofing for gypsum plaster is applied with a layer of mortar no more than 25–30 cm thick.
As an example, let's look at the instructions for self-plastering.
- Preparing the surface for plastering. Before applying plaster, clean the walls from dust, dirt and grease stains.
If the surface is not rough enough, we make notches with an ax to ensure greater adhesion. If you have sandblasting equipment, the work is greatly simplified. After all, it is possible to cover an entire wall with small notches not only quickly, but also with minimal labor costs.
Important: Cement-sand waterproofing can only be used on hard surfaces that are not subject to vibration. In addition, the application of enclosing plaster is allowed only after the construction site has completely settled.
When expansion joints (sedimentation and temperature) are formed during sedimentary processes, we fill their cavity with bitumen elastic mastic.
- Stuffing the reinforcing mesh. After the surface to be insulated is prepared, we attach a metal corrosion-resistant mesh chain-link to it. The main purpose of the mesh is to compensate for sedimentary processes and maintain the integrity of the plaster layer.
The mesh is selected with a wire diameter of 2-4 mm with a cage side from 10 to 40 mm. We roll out the mesh roll along the wall, lift it and fix it with construction nails or dowels. We attach the mesh in increments of no more than 40 cm.
- Preparing the solution. At this stage, it is necessary to prepare a solution that, when applied, will provide not only the required adhesion, but also demonstrate optimal strength properties.
The guarantee of the quality of the plaster mortar is compliance with the proportions. For example, the combination of cement and sand should be one to two. (Unlike cooking ordinary plaster). Water and other components are added with the expectation that the consistency of the material is uniform. And in density it resembled thick sour cream.
Important: Mixing of all components must be done mechanically. That is, you will need a concrete mixer. For insulation work on the walls of a low-rise building, a mixer with a drum volume of 100 to 200 liters will be sufficient. Such equipment can be purchased or rented.
In the photo - a sketch of cement
- Applying the solution to the surface. To carry out waterproofing work using plaster, you will need a trowel average size and plastering rule.
The surface to be insulated before finishing works spray with water from a spray bottle. Then we stand against the wall with our left side. And, taking the solution from the container in medium portions, pour it on with force. The movements of the trowel should resemble the movements of a ping pong racket.
Periodically spray the wall surface with water. This is done to ensure better adhesion of the outline. We spread the solution from bottom to top over a strip width of up to 1 meter. Then we take the rule into our hands. Smooth out the sketch using smooth movements from side to side.
Important: After the plaster is applied, the surface must be kept moist to prevent cracking. To do this, periodically water the surface of the wall with water from a hose with a sprayer over the course of a week.
Composition of cement-sand insulation
The photo shows an example of manual application of insulation
Behind for a long time Considerable experience has been gained in the use of plasters in the use of waterproofing coatings. As already mentioned, modern insulating plaster is prepared from dense cement-sand mortars in a ratio of 1:2.
In the manufacture of waterproofing plaster mortars, various chemical additives are used:
- responsible for filling pores and voids in the solution;
- responsible for the formation of neoplasms of a colloidal or crystalline nature in the process chemical reactions with cement.
- ensuring the waterproofness of the solution (plasticizing additives);
- giving the plaster mortar additional resistance to mechanical loads;
- providing additional adhesion to the wall surface.
Various components are used as sealing additives. Such as ground sand, cerolite, ceresite, ground coal, stone flour, bitumen emulsions, pure bitumen, etc. In addition, plasticizers are necessarily integrated into the solution. Namely, soap naft, abietic and rosin soap, oleates or saponified wood pitch.
Waterproof plasters with a layer thickness of 250 mm or more, applied from the side where water enters, are characterized by the greatest reliability. Water pressure and its tearing effect are characteristics that must be taken into account when making plaster and when selecting chemical additives.
Gunite as waterproofing
As another way to protect concrete coverings can be called shotcrete.
Statistics and repeated studies show the following advantages of using shotcrete:
- high mechanical strength;
- increased adhesion and, as a result, reliable adhesion to the concrete surface;
- high water resistance of the finished coating;
- resistance to sudden temperature changes during operation of the finished coating;
- Possibility of use on mechanically laid surfaces.
The disadvantages of using gunite on insulated coatings include the high probability of cracks forming during uneven settlement.
Asphalt waterproofing
Asphalt waterproofing is protective covering, consisting of several layers of hot asphalt mastic or a solution of emulsion mastic and viscosity-enhancing paste.
This type of waterproofing is applied with equal success to both vertical and horizontal surfaces. Asphalt plaster is recognized optimal solution for waterproofing ground floors and basements.
Methods for applying such plaster depend on the type of composition used. For example, hot plaster asphalt insulation is heated to a temperature of +180°C before application.
This method of application guarantees a high degree of hydrophobicity of the treated surface. But it is not always convenient due to the need to use special heaters. In order to simplify the application of waterproofing, cold mixtures prepared in the form of mastic are used. (Or emulsion paste.) This finish can be used for its intended purpose only after complete drying.
Asphalt plaster is applied to vertical surfaces using two methods: manually and mechanized. In the first case, special coating brushes are used.
In the second case it is used special device— asphalt thrower. The mechanized method of applying asphalt allows you to process large sections of walls in a short time, evenly distributing the plaster material.
Application of asphalt plasters
The preparation of hot asphalt plaster is carried out using mixtures of high viscosity. As a result, they can be applied to horizontal, vertical and inclined surfaces.
The mixture is supplied to the asphalt thrower by means of compressed air. Asphalt throwers on the market, in addition to a blower and working tools, are equipped with a mastic heater. As a result, the application of insulating material can be carried out both in warm and cold seasons.
Bitumen mastic is applied in layers up to 7 mm thick. The movement of the nozzle is arbitrary, that is, the coating can be sprayed both from bottom to top and from side to side.
During operation, the asphalt thrower nozzle is held perpendicular to the surface being processed at a distance of 50 cm from it. The total thickness of asphalt plaster is usually between 10 and 20 mm. Plastering work is carried out exclusively in dry weather. Or when using weather protection.
Cold asphalt waterproofing is a bitumen emulsion mastic. It is applied in several layers. Cold mastic is made directly on site or shortly before application. During the preparation process, bitumen paste is mixed with mineral powder with the addition of a small amount of water. Up to obtaining a single-consistency mass.
On large covers, cold asphalt mastic is applied using a diaphragm pump in combination with a compressor, mixer, hoses and nozzles.
The advantage of mechanized application of plaster is the ability to treat the surface of construction sites at a height of up to 15 meters. Laying of cold mastic is carried out at a general temperature of at least +15°C.
Conclusion
Now you know what waterproofing plaster is and how it is applied. It remains to figure out whether waterproofing is needed for low-rise residential buildings. Or should such finishing be used exclusively on large public or industrial facilities?
Of course, high-quality waterproofing is necessary for most structural elements. Regardless of the purpose of the building. Despite the fact that the price of professionally carried out waterproofing work is high, it is fully justified by the durability of the protected structural elements. (