Experiencing innovative biomaterials for buildings: Potentialities of mosses

Vertical greening systems and green roofs provide ecosystem services in the urban context. Despite the important benefits they provide, economic (initial and maintenance costs) and environmental issues may limit the widespread diffusion of these greening systems. Mosses can be a low-cost and low-maintenance alternative green envelope for large-scale application on existing urban and industrial buildings thanks to their low requirements in terms of growing substrates, low amount of water and nutrients needed, and high desiccation tolerance. The study assesses the’ growing ability of mosses on building materials and low-cost materials, by means of growing tests performed under controlled environmental conditions on horizontal and vertical surfaces. Moss growth depends mainly on the physical characteristics of the materials, although an acidic moss mixture improves species richness. Results show different surface coverage: capillary matting > cement plaster > lime plaster > terracotta brick > slate > quartzite. The water retention capacity and its homogeneous distribution on the growing surface are the limiting factors for moss growth.