EN Hans Valkhoff is an environmental researcher who lives in the Amsterdam area (Netherlands) and specializes in eco-building and retrofit of existing buildings. Between 2011 and 2018 he was an associated researcher and lecturer at the School of Architecture in Toulouse and he is a founding member of the French platform for responsible retrofit CREBA. He worked as a program manager for the Dutch Green Building Council in The Hague and now works as an advisor for the Amsterdam energy cooperative KetelhuisWG.

Hans holds a MA in Urban Geography and town planning from the University of Amsterdam (1989) and a MSc in Architecture and Advanced Environmental Sciences from the University of East London (2010). In France he restored a 17th century timber-frame house with vernacular materials such as wattle and daub, lime and clay renders and natural insulation materials.