Previous investigations of the first colonizers of modern building surfaces, especially of external thermal insulation compound system (ETICS), revealed that after a certain while certain mosses may be found amongst them. Usually fungal and algal colonizers are faster, but after only a few years, moss growth may start if conditions are favorable. The primary aim of the project between the "Royal Botanic Garden Edinburgh (RBGE)" and the Fraunhofer-Institute for Building Physics IBP was to obtain DNA barcodes of samples that are involved in the primary colonization of building surfaces (masonry), with special emphasis on the genus Schistidium.