The construction of a modern mountain hut nearthe mountains Matterhorn and Dufourspitze in the Swiss Alps is investigated from an environmental point of view. A prospective environmental assessment was performed to minimize the environmental impact already in the planning phase of the new building; construction will start in autumn 2008. An energy balance of the existing hut was made to detect optimization potentials and to predict the necessary energy generating systems of the new building. In addition to energy supply, the environmental impacts of materials and processes were compared and evaluated with the help of Life Cycle Assessment Although energy use will increase in the new building, mainly due to the installation of a wastewater purification system, total greenhouse gas emissions will decrease.