Ziegert | Roswag | Seiler Architekten Ingenieure was founded in 2003 as an integrated architecture and engineering design studio based in Berlin. Our two design companies, Roswag Achitekten and Ziegert | Seiler Ingenieure, unite a broad spectrum of services under one roof: architecture, structural engineering, building certification and energy planning, consulting services, material testing and development, as well as scientific research and teaching work. Our core competency is the use of natural materials, especially earth, in construction. Our projects range from earth and timber houses and a timber plus-energy workshop building in Berlin, through earth and bamboo schools in Asia and Africa, to the conservation of historic monuments on the Arabian Peninsula. We pride ourselves on our continued success creating comfortable and energy-efficient buildings in collaboration with a wide range of highly qualified partners. Natural construction materials address a growing worldwide awareness for the need to pursue healthy and environmentally conscious architecture. Natural materials such as earth and timber are energy- and cost-efficient as well as fully recyclable. Moreover, when used in construction they can absorb pollution, regulate air humidity and create a superior room climate. Our low-energy timber and earth houses, insulated with cellulose, do not require additional mechanical ventilation, thereby reducing life-cycle costs while maintaining high levels of end user comfort. We are trained energy consultants for both residential and non-residential buildings with a KfW certification as on-site consultants. As accredited DGNB (German Society for Sustainable Architecture) and BNB (rating system for new ministerial administration and office buildings) auditors we are able to provide sustainability consultation and certification under both of these systems. The integrated planning and realisation of complex construction projects in-house is a mark of our work. Our international network is founded on principles of positive communication and an awareness of different cultures; our projects seek to strengthen existing traditions through the use of local solutions. Our team is currently made up of 30 architects and engineers in Germany and abroad. Our work has been recognised by a number of competition prizes and awards including the Aga Khan Award for Architecture, Holcim Award in Gold 2011 and the KAIROS Prize 2015 as well as being featured in numerous publications.