The Filter is an appartment building in Votanikos area of Athens. We attempted to imitate the hospitable environment created under the foliage of a tree. The tree adjusts its form according to its surroundings trying to find the ideal conditions in which to grow. It rises high to reach direct sunlight and forms its shape filling the empty space in its surroundings. It creates a filter around itself - a foliage that protects its internal core. On the main facade a filter made up by plants and a surface of perforated opening metal sheets that act as a protective barrier filtering the incoming sunlight while blocking the view from the outside and protecting privacy. The building includes 10 apartments and 1 office space.