VIENNA (AT) - Like an exposed outgrowth of peridot, two loft apartments with accompanying terraces have been set atop a late 19th-century building in Vienna's city hall district. From the street, the glazed structure's form readily blends with the surrounding buildings, its integration with the existing skyline executed with plausible precision. Perhaps appearing at first glance like the naturally weathered patina of copper panelling, the structural glass facade's variously sloped surfaces form a modern exterior shell that corresponds to neighbouring buildings with fluid authenticity. With an eye to energy optimization, the architects have turned this attic space into a year-round climate comfortable zone.
Erected in 1873 by August Ritter von Schwendenwein, the building has been retrofitted with a new steel and glass lift in its courtyard and a glazed rooftop extension containing two spacious loft-style apartments with a main floor and a gallery level. There are terraces on both levels, and roof terraces accessible from the gallery floor terraces. Storey-height glazing with sliding sections faces the courtyard, and external louvered metal screens of anodized aluminium provide solar protection. On the building's street-facing side, internal solar shading is used, while projecting roofs with louvered sun screens help to shield the terraces.
A lightweight steel and timber construction forms the roof itself, and the roofing material is of pre-weathered zinc. The thermally insulated roof supplements heating and cooling arrangements in the interior spaces, where ceiling air fan coils and underfloor convectors have been installed. Heating and cooling systems are interlocked, utilizing the same distribution line with corresponding control valves. The heat requirement for the attic space and the apartments therein is approximately 35 kW. An energy-efficient condensing boiler in both dwellings provides heating, the levels of which are in turn determined by exterior temperatures and distributed by the air-conditioning system accordingly. Furthermore, an air-cooled water chiller located in the basement serves to cool the apartments in the warmer months, with a capacity of 25 kW for both. (Dutton R. Hauhart)
Conversion, Ecocentric, Glass |