The urban residential block with rental housing shapes a U where the open side faces two freestanding buildings and the nature behind. The block opens up towards the central park to the east and closes off towards Ulvsundavägen with heavy traffic to the west. The buildings have a range of heights from 4 to 8 floor levels with a playful roofscape and inner courtyard. Mattisborgen is part of Annedal, a residential area including parks, cafés, schools etcetera, and is positioned in the northeast of Stockholm. The masterplan is based on the winning proposal also designed by Tovatt Architects & Planners submitted for in an international competition in 2003 and further developed in close collaboration with the city. Two buildings within the block is built as ‘passive houses’, which means that they require no heating energy other than passive solar heating and heat generated from lighting and household electrical equipment. This places a high demand on the buildings insulation efficiency.