Blachodachówka coatings serve two main purposes: they protect the steel against corrosion and give the covering its appearance. When comparing them, check whether you are assessing the whole layer system rather than just the name of the paint. The metallic layer and the organic paint have different tasks, and their thicknesses are given in different units. Compare corrosion resistance, UV radiation, environmental conditions and warranty terms for the specific product. The choice should concern a particular product, not merely the type of paint.

Identify the green deposit on the metal roofing tile first, then remove it, because moss, algae and ordinary dirt require different methods. Check the type and adhesion of the soiling and the condition of the coating before choosing a cleaning method. Base the assessment on a trial in a less visible place if documentation for the covering is available. Also check that gutters, valleys and outlets are clear, since accumulated leaves trap moisture and can encourage the deposit to return. Remember that shaded roof areas and places near trees dry more slowly, so green marks may appear unevenly and need not indicate a fault in the sheet.