Defined by simple geometric rules, the modern AA House was designed by OAB and is located in Barcelona, Spain. According to the description provided by the architects, “the footprint of the building uses a superimposed 7×7 meter skewed grid to support the program in a composition similar to a musical score. The diagonals serve as a roof system that ungulates like an artificial topography, creating skylights in some cases, while in others situations, rising up double the height of other rooftop peaks. At the base floor, the program develops a direct relationship between the interior and exterior through the abundant use of glass-work, trellises, and sliding panels“. Most of the interiors are visually connected to the surrounding green spaces and are flooded in natural light from the generous windows. The bottom level accommodates the library, dining room, an inside swimming pool and an extension of the main bedroom, while the second level hosts the large piano room, with plenty of area for socializing.