Facade painting
Sunday, 26 June, 2022Do you want to repaint your facade? Read our how to´s and guides before you get started.
Wooden facade
Preliminary work: The weather should be warm and dry for several days before painting. Normally the best time for painting is from June to August (in Nordic countries), but regardless of the season, painting must be completed in time for the paint to dry before the arrival of the night dew or cold weather. Surfaces heated in the sun should also not be painted. New wood must be painted as soon as possible after installation. If the wood is painted indoors, it must be ensured that it is not too dry (moisture content 6-8%). For example, the wood dries when stored in a hot boiler room, etc., and can then expand outdoors when the maximum moisture content (12-18%) is reached. The elasticity of hard paints (various oil paints) may then be insufficient and the paint will crack.
To choose the right type of paint, it is important to know what paint the house has been painted with before. As a rule, the same type of paint should be used. Surfaces previously coated with acrylate paint cannot be overpainted immediately with hard alkyd paint because they have different elasticities and can therefore slip relative to each other during temperature changes. This increases the risk of cracking and paint penetration. Surfaces previously covered with distemper paint (e.g. Falu Rödfärg) must also be covered with the same type of paint. Before changing the paint type, all the old distemper paint must first be completely removed from the substrate
Here are some good tips to find out what paint the house has been painted in before:
– Sand the surface with a sandpaper. If the paint sticks to the paper, it is probably an acrylate paint. If the paint is dusty and does not cover well, it is probably an alkyd or linseed oil paint…
– A drop of alkali can be placed on a light surface. If the surface turns yellowish brown after a few minutes, it is an alkyd paint.
– Alternatively, rub the surface with a cloth soaked in denatured alcohol. If the paint becomes soft (dissolves) and comes off easily, it is an acrylate paint.
The base surface must be dry and firm. Loose paint is removed with a scraper and / or wire brush. Soft wood (rotten) is removed and replaced. Dirty surfaces are washed with a façade and mold cleaner and rinsed with water. Surfaces covered with fungi and mold are treated. After pressure washing, wait 2-3 weeks in dry weather to make sure that the water that has penetrated the cracks and under the panels has completely dried out.
Painting
The ends and joints of the logs must be carefully treated. Use the primer Utegrund 2-in-1 or Grundolja Aqua in combination with Utegrund Aqua. The classic combination of Grundolja Classic and Utegrund Classic can also be used. Paint 1-2 times over Titan Facade Paint, Storm Uteakrylat or Stabil Oljetäcklasyr.
Maintenance
Dirty facades are washed with facade cleaner and rinsed thoroughly. If the facade also has fungus and mold (black spots), the facade can be disinfected. To do this, apply a disinfectant and allow to dry for 1 day before cleaning with a facade cleaner.
Alkyd oil paints have a natural process of wear and fading, which is more intense on the southern and eastern façades with higher UV radiation. Therefore, these sides of the building may require more frequent maintenance.
Mineral facades
Preliminary work
The surface must be clean, firm and dry. Wash and rinse the surface and, in the case of fungi, treat with an antifungal agent. Allow to dry well. Old, loose paint is removed by using a wire brush or by scraping. Any holes and cracks must be filled.
Painting
Always paint previously painted surfaces with Betoprime. Then apply 1-2 coats of Betopaint with a roller or brush. After dilution, a spray can also be used, read more on the package. Do not paint with more paint (putting on a thicker layer) than necessary to achieve good coverage, putting on one coat is usually sufficient. This is how the openness to diffusion required for surfaces works best.
Maintenance
In case of dirt or plant growth, wash the surface with a suitable facade cleaner and rinse thoroughly with water. In the case of fungi, disinfectants may be used.