Use of recycled and waste materials as part of the substrate of green roofs

Recycled and construction waste materials can significantly reduce the consumption of non-renewable resources, especially minerals. These materials can also be advantageously used as part of the substrate of vegetated roofs. The decline in biodiversity is one of the major environmental problems today. Of the conventional vegetated roofs, brown and biodiverse roofs are closest to nature, as they are planted with local plant communities. The two types differ in the way they are greened. Biodiverse roofs are planted with seeds or plants at the time of construction, while the substrate surface of brown roofs is left to succession (plant propagation through emergent vegetation and spores). These types of roofs are the most natural urban feature that can contribute significantly to biodiversity conservation. They are low maintenance and do not need to be watered.