Plaster on wood: types and features of application

The technology of plastering on wood is no different from plastering surfaces from other materials. Wood has always been the most affordable material for building houses.

Today, wood is pre-processed before building a house:

• antiseptics against decay and mold;
• impregnated with fire-fighting compounds and mixtures;
• primed with impregnations to level out the color;
• varnished to protect against aggressive environmental factors.

As a result, the house turns out to be beautiful from the inside and outside. But wood with numerous layers of impregnation and varnish can no longer emit anything into the atmosphere. It should be borne in mind that all impregnations must be repeated at regular intervals.

The decision on whether to plaster the facade of the house or not is best taken at the stage of construction planning. In this case, you can choose a cheaper option for wall construction. You can use materials with a lower frequency of surface finishing, and this will provide tangible savings in the procurement of materials. Plastering of the facades of log houses is carried out at least 1.5 years after construction.

First, let's figure out which mixtures are better to choose for plastering wooden surfaces. Below we will consider the options for mixtures that are better suited for plastering internal walls, and which ones for external ones.

The cement-sand mixture is the simplest and most affordable. Consists of a mixture of cement and sand, the ratio of which ranges from 1: 3 to 1: 5, depending on the brand of cement and the required brand of mortar. Prefabricated mixtures also contain plasticizers. The composition can be used for plastering wooden surfaces both indoors and for facade work. But the mixture is quite "tough", and in its pure form it is inconvenient to work with it.

The cement-lime mortar has good adhesion to wood surfaces. The presence of cement in the solution gives it frost resistance and water resistance. It is used for both interior and exterior walls. You can buy a ready-made dry mix, but it's better to prepare it yourself.

To do this, you need to prepare:

• 1 part of grade 300 cement;
• 4 parts of medium size sand, it must be sifted and not contain large stones. In the case of using cement grade 400 or 500 sand, we take 5 parts.
• 1 part slaked lime. Lime should be slaked at least three days before use. On the packaging with quicklime, the time for slaking the lime is indicated. It should be borne in mind that the quenching reaction takes place with the release of a large amount of heat. Therefore, the appropriate dishes must be selected and precautions must be taken. We add water gradually. Until a homogeneous mass of sour cream consistency is obtained. The resulting lime must be filtered. Filter again before use. When using incorrectly slaked lime, the plaster will crack. Ready-made slaked lime is sold - fluff, so it is better to buy it.

We mix sand and cement in a dry state. We begin to gradually pour in the milk of lime with constant alteration. You should get a homogeneous mass of sour cream consistency. The volume of the prepared mixture should not exceed the volume of production per day. Lime in solutions gives them plasticity, increases water resistance and is an antiseptic, which is especially important when used for plaster on wood in new homes.

Lime-gypsum mortar is a mixture of gypsum and dry lime. Plaster solutions containing gypsum are used only for interior work in dry rooms. Plaster solutions containing gypsum are afraid of moisture. The setting time of gypsum is less than 30 minutes and depends on the temperature of the mortar - the higher it is, the faster the setting. Therefore, it is better to plaster internal walls and partitions with gypsum solutions. It is necessary to plaster quickly and accurately.

Clay plasters are the oldest material that has not lost its relevance today. Remember at least the huts of the hut in the south of Russia. Clay should be free of mineral particles, root residues and solid inclusions of sedimentary rocks. It is better to buy ready-made clay mixtures factory-made.

A clay-based mortar for plaster on wood is prepared as follows:

• Clay - 3 parts;
• 4 handfuls of straw (per ten liters of clay); straw can be replaced with sawdust of coniferous wood, oak or alder;
• Sand - 7 pieces;
• 100 grams of non-woven wallpaper adhesive per bucket of water.

We dilute the glue in water. Pour in a thin stream into the resulting mixture until the required consistency is obtained. The clay solution remains plastic for a long time, so the mixture can be prepared for the whole day.

When using a clay-based mortar for finishing external walls or damp rooms inside, add 1 part of cement of a brand not lower than 400.

The readiness of the solution can be determined by cracking. Roll a ball 3-4 centimeters in size and squeeze between two plates. If 3 or 4 shallow cracks have formed on the resulting cake, then the solution is ready. If the ball is scattered, then the solution is "skinny" and it is necessary to add clay to it. In the absence of cracks, the clay is oily and sand must be added.

For the production of work independently, you will need tools and equipment. The list below is indicative only. For example, instead of scaffolding, you can use "goats".

Some positions can be completely excluded:

• scaffolding or stepladder;
• power tool - electric mixer, screwdriver, electric extension cord;
• containers for work - a tank for mixing the solution, buckets for transporting the solution, a cuvette for the solution;
• plastering tool - bucket, falcon, usually a grater, a trowel, spatulas of different sizes;
• mallet for caulking.

It should be borne in mind that plastering of wooden houses is allowed only 1.5 years after construction, so that the tree is completely dry. Plastering of frame-panel houses can be carried out immediately after the completion of construction.

Stages of work:

• We fill all existing cracks and crevices with polyurethane foam or caulk. We remove oil and bitumen stains from all surfaces, if any. We carry out caulking of the outer walls of the house from the inside and outside.
• We treat all surfaces with an antiseptic to prevent the appearance of mold and mildew. If there are sections of walls or other surfaces that are not made of wood, for example, a concrete basement or an abutment to a wall made of another material, we treat these surfaces with concrete contact.
• If it is necessary to plaster wet rooms, we make waterproofing inside. The easiest way to do this is with roofing felt or plastic wrap.

• We nail a metal mesh onto the outer walls and basement.We fix it with special mushroom dowels. The mesh should not have sagging. We nail the reinforcing mesh to the inner walls. It happens that there are local areas in which the thickness of the plaster turns out to be more than 3 cm. This happens when there are deviations of the walls from the vertical by more than 3 cm or the internal corners are more or less than 90 °. In this case, after spraying, we attach another layer of mesh.

• Shingles. Begin to nail from below at an angle of 45 °. You should get rhombic cells 50x50mm or 45x45mm in size. On vertical surfaces we nail them through three cells. On the ceiling - through two cells. When extending the tape, leave a gap of at least 5 mm between the ends. We moisten the ends of the tapes and nail each end with nails. Although, in its absence, you can make a shingle yourself, having a table circular saw at home, by sawing it from boards or slats of suitable size.
• Polymer reinforcing mesh for masonry works is fixed with self-tapping screws with a wide head. The number of self-tapping screws is 10-12 pieces per square meter. The basic rule when attaching such a mesh is that it should be stretched like a string. Joints at vertical corners are not allowed. At the junction of the mesh webs, we make an overlap of at least one cell.

Plastering work is a wet process, so they need to be planned for the warm season. It is optimal to choose the moment when there is no rain.

Stages of work:

• Spray. Prepare a more fluid solution than usual and spray it with a ladle over the prepared surface, starting from the top. We control the thickness so that the layer does not exceed 9-10 mm. We proceed to the next stage after the first layer has completely dried.

• The main layer. Apply a solution of normal consistency over the first layer. We align with the beacons. We start plastering from above.
• The final layer. Elimination of minor defects in wall surfaces, maximum alignment with beacons.
• Grout. Sanding and grouting of walls, obtaining a flat surface. This is especially true if wallpapering is planned.

It is irrational to perform plastering work alone, it is better to work with an assistant, and even better not with one.

The minimum link for plaster is 3 people, while it is better to have 2 links: 1 master plasterer and 2 apprentices to prepare the mortar and carry it. They also rearrange scaffolding or scaffolding.

After finishing the external work, you can start plastering the internal walls. It is better to start work inside from the ceilings, and only then plaster the walls so as not to spoil the already finished surfaces with a spray of mortar. We complete the work inside the room completely and only then move on to the next room. The most correct option is to start plastering from the farthest room from the entrance, gradually moving towards the front door. With this direction of work, the premises are closed for drying one by one. Accordingly, with proper drying, finishing can begin in the same order.

The basic rule for drying plastered surfaces is that for the first 3 days we do not use anything to speed up drying. Accelerated drying results in the quickly dried top layer preventing moisture from escaping from the underlying layers. Subsequently, such plastered surfaces crack. Accelerated methods can be used on the 4th, and preferably the 5th day. Drying can be accelerated by ventilating or heating with a heat gun.

The plastered surfaces of the outer walls must be protected from both accelerated drying and rain. In the case of facades, heating by the sun's rays is added to the negative factors, especially in windy weather. Therefore, it is better to immediately prepare a protective film and immediately close the walls with it. It will protect both from rain and from the sun with the wind.

How to prepare wooden walls for plaster, see below in the video.