The city of Vienna strongly supports the establishment of green walls. The green wall on the side of the MA48 office building was built in 2010 and has been under constant monitoring ever since. The city’s first green wall system is 450 m2 in size and consists of more than 3,000 m of lined stainless steel planting containers. The properties of the green wall are monitored with various sensors and its irrigation is provided by an automatic irrigation system. The summer cooling effect of the green wall is equivalent to the operation of 80 air conditioners of 3000 W each, 8 hours a day. The building’s winter heat loss was reduced by about 50% with the construction of the green wall.