A Horizontal flow constructed wetland (HFCW) greywater recycling system is designed and installed by alchemia-nova GmbH at the apartment complex FELZ ZWEI, which was realized by VBAU Architecture in Zürich, Switzerland in 2021. ZHAW was evaluating the cleansing capacity and water quality; the potential water, energy and financial savings; as  well as the user acceptability of reusing treated greywater for toilet flushing and garden irrigation.