Which shades are suitable for the exterior facade of the house to guarantee high UV resistance? I suppose not all shades are colour stable.
Colorants with high UV resistance are preferably selected for the tinting of façade paints. However, some shades are problematic in terms of UV resistance. These are some bright red shades and shades of orange.
For renovation, we recommend to use a colored undercoat before applying a finish coat of a bright color especially for yellow and orange to red colors. On external walls exposed to the sun, building regulations DTU 59.1 and 42.1 advise against the use of colors which absorption coefficient of solar radiation is greater than 0.7 (Y, index of luminance, < 35%). These colors are marked in CHROMATIC fandeck with a “crossed sun pictogram”. This limitation is not linked to a lack of resistance of the color to light, but is intended to protect the wall from thermal shocks that may create significant problems in respect of the masonry and the paintwork.
We recommend to use also our special fandeck CHROMATIC FACADE colour chart that is designed to meet the needs of professional painters, architects and building owners for all façade or exterior projects. Colours are made from inorganic-mineral pigments providing improved coverage as well as resistance to chemicals and strong sunlight. In some countries, standards and rules governing thermal insulation systems may recommend the use of paints with a low coefficient of absorption of sunlight so they minimize heat absorption.