Plastering of walls is an invariable process of finishing the base before wallpapering or painting. Learn about the rules for choosing a material to obtain a flat surface with minimal roughness and how to apply it from this article. Putty is a paste-like material for leveling the wall surface before painting, wallpapering or other decorative elements. Putting is an obligatory operation in finishing works.
The main types of putties for walls
The putty is made up of three main components - binder, filler and solvent. The filler is most often sand, the solvent is water, sometimes drying oil, but the binder can be anything, the characteristics of the working material depend on its type.
Classification of putty for walls by composition
Cement putty is considered a type of cement mortar. To obtain the substance, cement grade 500 or 400 and river sand are used as a filler, which is valued due to its small crystals and a small amount of impurities. After hardening, the coating becomes very tough and cannot be accidentally destroyed.
Cement putty is water resistant and is often applied to walls in bathrooms and other areas with high humidity. It is allowed to use this type of coating for finishing facade walls. Does not deteriorate at low temperatures.
Cement putty is gray in color, therefore it is not used for surface treatment under light wallpaper, it can shine through. The disadvantages include shrinkage of the material after drying and excessive rigidity of the coating, which can become a reason for the formation of cracks after finishing the putty of the walls.
Gypsum putty is made from a gypsum mixture. It is used at the final stage of wall leveling to create a perfectly equal surface for painting or wallpapering. After plaster processing, wallpaper of any color can be glued due to the ideal whiteness of the wall.
The mixture does not shrink, is flexible, easy to apply and remove. It contains no harmful impurities, and mold and fungus do not take root on the surface. Gypsum does not like moisture and is used in dry ventilated rooms - the putty swells under the influence of water. Quick drying of the mixture can create some difficulties for users.
Polymer putty is made using chemicals. It does not absorb water, is not afraid of temperature changes and precipitation. The material is elastic, applied in a thin layer, does not crack and shrink. The solution is often used to seal the cracks that have formed under the influence of water. Users may not like only one thing - the high cost of the material.
Of the polymer putties, the most popular is acrylic. It is convenient for household use when it is not possible to select material for each specific case. Can be applied in thick and thin layers.
A number of putties include drying oil. Glue putty consists of 10% of glue, drying oil and chalk, the coating is very durable and elastic.
Oil and glue putty, in addition to drying oil, contains plasticizers. It is applied to concrete or wooden walls, it is used for interior work. It is indispensable for wall decoration before painting in wet rooms. This putty is applied to walls that do not require high-quality finishes, for example, in sheds, closets, bathrooms. It protects the surface from destruction by fumes. Oil-glue putty protects wooden walls from decay, and fasteners - from corrosion. After processing, the wall is painted with oil paint.
Separation of wall finishing putty according to purpose
The mixtures contain components that perform well under certain conditions. In order not to spoil the wall with the wrong coating, study the features of working with each type of putty:
- The starting putty is applied first after plastering in order to eliminate layout defects, large wall drops, filling holes and wide gaps. The thickness of the layer can reach 2.5 cm. It is distinguished by the presence of components with coarse fractions, therefore the coating has high strength characteristics. Usually cementitious compounds, gypsum and chalk, as well as a variety of chemicals act as astringent. After processing, the wall takes on a gray tint.
- The finishing putty is applied on top of the starting filler to obtain a flawlessly even white surface. Without such treatment, all surface irregularities will be visible on the decor. The mixture contains fine-grained components, so the surface is very smooth, silky to the touch. The material is well processed with the simplest abrasive tools. The maximum layer of finishing wall putty reaches 3 mm.
- Universal formulations combine the properties of a starting and finishing putty. Allows to obtain a durable high quality surface after applying one layer of plaster. The disadvantages include the high cost of the material. Universal putties are very durable, they are gray in color, which is why they cannot be applied to all walls.
The choice of putty on the walls according to the base material
When choosing a mixture, be guided by the composition of the building material of the base wall: the binder in the plaster and the partition must be the same.
The criteria for choosing a putty on this basis are as follows:
- Walls of brick, concrete and plastered with cement mortar should be finished with cement putty.
- Any surfaces are finished with gypsum mixtures, but the best indicator of adhesion will be when processing drywall.
- All walls can be putty with polymer compounds.
- The scope of application of the mixture is usually written on the packaging, therefore, in order not to be mistaken with the choice, read the recommendations of the manufacturer.
The scope of application of the mixture also depends on the dispersion of the particles of the substance:
- Mixtures for putty of wooden walls contain deeply dispersed particles (200 microns in section), they are in good contact with wood.
- Walls made of bricks or covered with sandy-clay plaster are recommended to be putty with fine mixtures (15-20 microns).
- Artificial wall coverings interact well with medium-dispersed putties (59-80 microns in section).
- The dispersion of the putty is usually indicated on its packaging, which makes it easier to choose the material.
Types of putties for walls by phase state
The material is sold in a paste or powder form. Each type has its own advantages and disadvantages, and the user must consciously choose the coating.
The finished mixture is sold in cans and can be spread immediately. This type includes water-dispersed putties. The mixture has a consistent viscosity and increased strength due to industrial production. After work, keep the unused putty in a closed container, otherwise the substance will lose its qualities. The shelf life of the product is much shorter than that of dry materials. Ready putties save time on mixing, there is no dust during work. Please note that a prefabricated mixture gives a large shrinkage, so it is applied in a layer of up to 2 mm.
The dry mixture is stored in bags and bags, has a long shelf life. Before use, it is diluted according to the instructions on the package. The cost of the material is lower than that of the finished mixture. Dry gypsum-cement plaster is intended for processing the plane under the wallpaper. The mixture for living rooms is indicated by the indices LR and KR, for wet rooms - VH.
Preparatory work before plastering the walls
Puttying requires care and does not tolerate interruptions. To keep the main process going continuously, perform a number of preliminary works.
Choosing a tool for applying putty on walls
A high-quality surface cannot be obtained without special tools. The minimum set of building accessories for do-it-yourself wall putty looks like this:
- Drill with a mixer for mixing the mixture. Used to prepare a solution from dry material.
- A set of spatulas in sizes from 80 cm to very small. A large tool reduces work time, a small one allows you to work in inaccessible places. To work with corners, you will need corner spatulas.
- Accessories for putty primer - large rollers and brushes. After priming, a thin hardened layer of putty is formed, which ensures good adhesion of the material to any decorative material.
- The rule is used for leveling a thick layer of putty, as well as for surface quality control.
- Lighthouses are metal profiles that are fixed to the wall and serve as bases for controlling surface treatment.
- A laser or other level is needed to control the finish of very uneven walls. With its help, beacons are exhibited to level the putty.
- Sandpaper, skins, mesh jointers - abrasive tools for surface grinding.
- Immediately before work, wash the working tool and wipe with cotton wipes. Inspect mixer and kneading container for old, dried putty. If found, delete it.
Pre-treatment of walls before putty
The putty cannot be applied to an unprepared wall, it simply will not stick to it. Before starting work on finishing with putty, check the condition of the base and carry out rough processing according to the following recommendations:
- The putty is applied only to the plastered surface.
- Remove old paint and loose plaster from the surface.
- Remove oil stains, paint or grime. Make sure that there is no part of the formwork left on the wall, the remains of scale.
- Do not start work if the walls are frozen.
- Eliminate large defects with a solution that is kneaded from sand and cement in a 3: 1 ratio. Small ones will be eliminated with starting putty.
- After filling the problem areas, allow the mixture to dry and then prime the wall with a deep penetration primer. Apply the solution in one layer without gaps. If you have doubts about the adhesion of the putty, cover the partition with a 10% solution of PVA glue.
Preparing a mixture of wall putty
Preparation of a solution from a dry mixture is carried out according to the instructions on the package of the mixture. In its absence, you can use universal tips:
- Pour clean water into the bucket in the amount indicated on the packaging of the material. Usually, no more than 1/3 of a bucket of water is poured.
- Pour the dry mixture into the water in a thin stream until the top of the powder appears above the water.
- Wait for the pile to get wet and sag. After 20-30 seconds, knead the solution with a drill and mixer for 1 minute.
- Turn off the drill and wait 1 minute, then continue stirring until smooth, pasty, no lumps allowed. After removing the mixer from the solution, a non-disappearing trace should remain in the bucket.
- For a thick layer of putty, prepare the solution thick.
- Before applying the putty to the walls, pick up the mortar with a spatula and tilt it in different directions. The mixture should not slip in any position of the spatula.
- Water and powder cannot be added to the solution, even if the consistency of the solution is not satisfactory, apply as it turned out.
- Before kneading, find out the hardening time of the mixture, the amount of a one-time batch should be enough to produce it with a margin of 25% in time.
Do-it-yourself wall putty technology
Putty work is carried out in a certain sequence, only adherence to the technology will allow you to get a good result.
Applying the first layer of putty to the walls
At the initial stage of work, the first layer of coating or starting putty is applied. Consider the features of wall finishing with starting putty for various volumes of work.
The most common defects when leveling walls with putty at the initial stage are local cracks and potholes. For work, you need a medium or wide spatula.
Sequence of works on filling cracks:
- First, widen and deepen the gap a little, then scratch the walls with a knife and prime.
- Fill the gap with mortar. Often, a masking net is used to strengthen the putty, which improves adhesion to the base wall and prevents cracks.
- During work, do not pull the spatula, grouting is carried out in sweeping movements, crosswise, ensuring uniform pressure of the tool. After periodic movements with a spatula, the putty will disperse itself as it should.
- Movements are stopped when the mixture fills the slots flush with the main surface.
To putty a large surface, follow these recommendations:
- The solution is applied in stripes with about 15% overlap. The putty that appears on the sides is not removed, it is removed after drying.
- Putty is done with two spatulas. One is a worker with a width of 60-80 cm, the other is a small one, with whom they collect the mixture from a bucket and apply it to the tool. For work, it is enough to apply 15-20 cm of solution to the tool.
- Drive the spatula diagonally along the wall, which allows you to process the wall horizontally and vertically at the same time.
- If you are right-handed, start from the left side of the wall for convenience. In this case, the applied material will be overlapped with a new layer applied from the right side.
- While working, try to maintain the same pressure, which will ensure an even thickness of the putty.
- To obtain a layer thickness of 2-4 mm, hold the tool at an angle of 20-30 degrees. Decreasing the angle increases the layer thickness and vice versa.
- Once dry, remove any beads from the surface with a sandpaper or other abrasive.
- Check the quality of the wall putty with a long rule and a flashlight, no gaps between the rule and the wall are allowed. The protrusions are removed with an abrasive, the depressions are sealed with grease with putty.
- Use an angled spatula to work the corners. There are no fundamental differences between putty on corners and flat surfaces, but working with complex surfaces is more painstaking, and may require several approaches.
- After obtaining the desired result, let the wall dry well, and then walk over it with a mesh jointer with mesh No. 80-120. The larger the number, the smaller the grain size. First, make circular motions with a jointer, then wide crosswise motions. Check the quality of the wall putty under the wallpaper with a rule and a flashlight. With good results, wallpaper can be glued.
There is a special version of the starting wall decoration - lighthouse putty. It is carried out using special profile rails that are attached to the wall in a vertical plane. After applying to the wall, the putty is leveled with a rule that relies on beacons. They control the position of the profiles with a level; for fastening to the wall, use gypsum or other fast-hardening mortar. The distance between the beacons is arbitrary and depends on the length of the rule that is available. In this way, even the most humped wall can be leveled.
Finishing the walls with putty
The finishing putty is designed to obtain a perfectly smooth surface for painting, because the surface of the wall for painting must be processed better than for gluing wallpaper. With its help, the smallest surface defects that remain after the starting putty are eliminated. The solution is applied in a thin layer, therefore, the finishing treatment will not correct the poor-quality initial wall finishing.
Tips on how to level the wall with putty to obtain a perfectly smooth surface:
- For a very thin layer, moisten the wall with plenty of water. If this is not done, moisture is instantly absorbed, the solution loses its elasticity, and it is difficult to level it.
- If you plan to use acrylic paint, use a particularly strong white putty.
- After the walls have dried, the coating is rubbed with a mesh jointer with a number of at least 150.
- To obtain a mirror shine, the wall is rubbed with a plastering trowel with suede. After filling the walls for painting, they are carefully primed.
The putty should dry under certain conditions: sunlight should not fall on the treated surface, there should be no drafts in the room, the use of heaters is not allowed. Ventilation should be internal, without strong air currents and noticeable temperature changes in adjacent rooms.
The drying time of the decorated wall depends on the type of putty mixture, usually it lasts up to 12 hours. Experts recommend continuing work in 24 hours.
Watch a video about decorating walls with putty:
The puttying process is not complicated, but laborious and takes a long time. An even smooth surface can be obtained by observing the established procedure and the ability to work with a finishing tool.
