For facade repair
It does not matter whether to renovate the facade of a large object or a small private house – first you need to find out what to do, and then choose the optimal option. There are two ways to save money – if you buy the cheapest materials, the amount of work and costs will increase, and the quality will not always be guaranteed, if you buy new materials that allow you to work professionally and quickly, they will be relatively more expensive. If the facade repair in a private house is done by yourself on weekends, you can afford to save by buying cheaper materials. If the object is large, the more expensive multi-component finishing materials will allow you to save a lot.
Facade finishing should begin with its preparation – the condition should be clarified and any damage should be identified. It is best to invite an expert for this purpose. The most common cause of facade damage is water. Therefore, all gutters and the roof must be arranged. Then windows, doors and other facade parts must be covered with a protective film. The surface must be dry and clean and free of dust, lime or oil. Particular care must be taken to ensure that there are no grease, wax, emulsion or oil residues on the façade. It is recommended to clean the facade mechanically – to cut off the pieces that have already been partially detached, to clean the peeling paint with a scraper. One of the most effective methods is to use high-pressure sand, air or water jets.
If more than 30% of the old plaster area of the facade is damaged, it is best to take it off and plaster it again. If the facade is still in good condition, all that is needed is to fill the cracks. Fillers can be based on cement, acrylic or PVC. Smooth the slightly dried surface with a lightly dampened sponge. To obtain a high-quality surface, the area is processed with sandpaper.
The next step is surface priming. It is important to assess whether the plaster needs to be primed with a deep primer. It is designed to strengthen old, weak, dry surfaces, improving their adhesion to various surfaces, as well as reducing water absorption. However, experts recommend priming all porous and moisture-absorbing cement, concrete, aerated concrete, gypsum, gypsum board, cement-lime and other surfaces. Apply the primer to the surface evenly once with a brush, low pressure sprayer or roller. If the surface is very old, damaged, strongly absorbs water, is unstable, it should be applied two or three times. The next layer is applied when the previous layer has dried. Old lime plasters must be primed, otherwise they will not be able to withstand the heaviness of the new layers, but you should not get carried away with the deep primer, because it reduces the air permeability of the walls when it penetrates deeply, and the building breathes worse.
Insulation is not a cheap pleasure, but it should be done, because the heat loss through the walls is the highest among all the heat loss sources – almost 50%. In Northern European climate, insulation definitely pays off, allowing significant savings at the expense of heating. Two materials can be chosen for facade insulation – mineral wool or expanded polystyrene boards. When using expanded polystyrene, insulation costs at least half as much, but it is only recommended for relatively new buildings that do not have moisture problems, because expanded polystyrene breathes poorly. Stone or glass wool is air permeable and can also be used to insulate damp wooden buildings. All mineral wool can be considered safe, because both stone and glass wool are made from natural raw materials.
The advantage of expanded polystyrene is its cheapness. Care must be taken to choose the right degree of hardness of polystyrene foam – otherwise, even the mechanical strength of a properly treated surface will be too low. Styrofoam is a combustible material. When working with expanded polystyrene boards, they should not be left in direct sunlight for a long time, as the material loses its properties, becomes brittle and loose.
Exterior wall insulation
The process itself is quite simple, but requires a relatively large amount of work and time. The facade must be clean, cracks filled and the surface leveled. If the façade has large irregularities, the polystyrene foam plates themselves can also be used for correction. It will require less work and resources than removing roughness when applying putty or decorative plaster. In addition, an uneven layer of topcoat may later crack.