Hoadl Peak at an elevation of 2,340 meters and its Hoadlhaus Lodge is one of Tirol’s most beautiful on-mountain ski restaurants. The Hoadlhaus Lodge provides seating for up to 600 visitors during the winter season and offers meal services from 9 am to 4 pm. The Restaurant can attend 200 guests, the wintergarden up to 400. Busy hours at the restaurant area depend on weather conditions. On good sunny days many more people will come and enjoy the sun at the wintergarden´s open southside front despite low outside temperatures whereas on days with poorer weather conditions less people will come and guests rather sit and enjoy their meal in the restaurant´s protected area. The architectural design of the wintergarden include huge glass windows on the southside which can be completely opened in order to adapt to local weather conditions as well as fully glazed facades to the East and West with spectacular panoramic views. The results of the sunpath analysis at the wintergarden area as well as sun simulations of the building complex have proved that additional heating systems are not necessary due to the high daily solar gains. Solar gains help heat the massive structure´s elements. Air temperature will then increase during the late morning hours up to aproximately 20 K above outside air temperature. During foggy, cold days on the other hand, the wintergarden turns into a wind-protected puffer space with temperatures reaching no more than 10 K above outside air temperature. It has been shown that waste heat from the kitchen´s service is much higher as the air heating demand. This is why heat recovery from this area is used during day service to cover heating demand for supply air.