Natural light, ample space and an inspiring environment are essentials “for architects to work properly”. All of those qualities are present within the courtyard and in the vicinity of an old block of housing in Smichov, Prague.When several young architects looked for a suitable place for their new studio, they came across an old, shabby building that used to be a prison, then a lacquer’s workshop, a sculptor‘s studio and most recently a blacksmith´s workshop. Having been refurbished many times and lacking proper maintenance, there was little left of the original, historically valuable building.After surveying and some evaluation, a decision was made to demolish a substantial part of the old building. The one-storey, U-shaped building was turned into a two-storey structure with a simple rectangular outline. It‘s ground floor houses a meeting room, a model-making workshop and toilets. The large, open-space atelier is placed on the upper floor. All of the spaces are naturally lit by strip windows facing the courtyard and by a linear skylight.The studio is placed at rear of the courtyard, which is accessible from the street by a passage through the old block of flats. The three stone and brick walls that were left from the original building are placed at the edge of the courtyard. The new structures, framed with solid wood timbers, were inserted in to the space defined by the old walls. The cladding between the wooden bearing members was made of fire-resistant cement panels.Thanks to its constrained position between the stone walls, the building has only one open facade facing the courtyard. Semi-transparent resin and fibreglass corrugated panels were used for cladding and for the shallow sloping lean-to roof. The light-weight character of the building envelope contrasts with the old heavy stone walls and goes hand-in-hand with the interior concept, based on the visible-bearing-structure principal. The internal room of the penthouse is thus mentally and physically interconnected with the external courtyard space.