TY - CONF A1 - Klinge, A. A1 - Roswag-Klinge, E. A1 - Ziegert, C. A1 - Fontana, Patrick A1 - Richter, Matthias A1 - Hoppe, Johannes ED - Habert, G. ED - Schlueter, A. T1 - Naturally ventilated earth timber constructions N2 - Earth, timber, fibre boards and insulation materials based on wooden and other natural fibres offer a variety of properties beneficial for eco innovative constructions that are able to improve the energy and resource efficiency of buildings. Due to their porosity, natural building materials are vapour active and are able to buffer moisture. In combination with highly insulated and airtight but vapour permeable building envelopes, modern earth-timber constructions provide stable indoor humidity levels and can therefore be naturally ventilated while achieving highest energy efficiency standards. Experimental evidence suggests that monitored pilot buildings in Berlin do show healthy indoor air humidity levels (around 50%) in wintertime, while mechanically ventilated buildings demonstrate significantly lower values (around 25%), which have to be considered as uncomfortable and unhealthy. The application of building materials being poor in chemical emissions, particularly volatile organic compounds (VOC) and radon, improves the indoor air quality further, so that intermittent ventilation twice a day will be sufficient to provide healthy indoor air quality. The air quality in critical rooms (e.g. small bedrooms), demonstrating a smaller air volume, should be monitored if appropriate ratios of room size to occupancy level cannot be realised. Through night time ventilation in summer, vapour active earth-timber constructions provide evaporative cooling (humidity adsorption at night time and desorption during the day). As a result, indoor temperatures of earth-timber buildings range around 8 °C below the outside temperature peak, when an appropriate glazing ratio is reflected. The EU funded research project H-house is investigating various construction materials regarding water vapour adsorption as well as emission and absorption of harmful substances. Based on this investigation new wall constructions are designed to provide a healthier indoor environment. T2 - Sustainable Built Environment (SBE) Regional Conference - Expanding Boundaries: Systems Thinking for the Built Environment CY - Zurich, Switzerland DA - 15.06.2016 KW - Building materials KW - Climate control through building elements KW - Hygroscopic earthen and wooden materials KW - Natural ventilation KW - Airtight building KW - Low emissions PY - 2016 SN - 978-3-7281-3774-6 U6 - https://doi.org/10.3218/3774-6 SP - 674 EP - 681 PB - vdf Hochschulverlag und der ETH Zürich CY - Zürich AN - OPUS4-37201 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -