O4 House, an oasis of nature in the city

Completed in 2011 as part of a project by Croatian practice Sirrah Projekt (Helena Alfirević Arbutina and Dražen Arbutina with the collaboration of Mislav Salitrežić) costing a total of 1,300 euro per square metre, the O4 House is a 400 square metre single-family villa close to the river Drava in the western area of Osijek, a city on the border between Croatia and Hungary.
The house is positioned in the centre of a long, narrow 2,000 sq.m lot with the main driveway and pedestrian entrance located to the north. Flanked by a large green area with meticulously manicured flowerbeds, the driveway not only provides access to the house and the two garages but also serves as a buffer zone for traffic and the outside world. The O4 House is positioned transversally with respect to the lot, dividing it into two parts and creating a second completely private rear garden overlooked solely by the two bedrooms.
The floor plan was dictated by the desire to create three clearly separate functional areas and at the same time to preserve two walnut trees already growing on the lot. On either side of the rectangular-plan central volume, positioned transversally with respect to the lot, there are two wings, also rectangular, which extend southwards. With the exception of the double-height living area, the house comprises a single above-ground floor with sophisticated, modern yet informal rooms. The heart of the house is a brightly-lit daytime area that separates the public sphere (the view towards the road and the city beyond) from the more private internal area of the property. It consists of an entrance hall, a living room with a mezzanine library, a kitchen with adjoining pantry and dining area. The two side wings house the night quarters and leisure areas in separate non-communicating sections: in the east wing the master area with double bedroom, bathroom and a wellness area complete with gym and whirlpool opening onto a private patio; in the west wing the children’s space with bedroom, bathroom and playroom.
The choice of materials and colours for the interior and exterior décor was determined by a desire for contact with nature and consist of neutral tones enlivened by warm wood touches. On the exterior, the ventilated facades clad with walnut finish Trespa laminate enhance the curved plastic volume of the main structure, while wood, stone-effect porcelain (Pietratech series from Cotto d’Este) and gravel are used for the paving area that emerges from the greenery of the English-style lawn. Inside, there is a pervasive sense of lightness that is particularly evident in the central volume, in the transparency of the glass panels of the partitions and the balustrades, in the visually-striking open staircase with wooden treads mounted on a single continuous beam, and in the carefully chosen colours of white, grey, beige and brown that dominate on the Kerlite ultra-thin porcelain floor tiles and the sparse but elegant furnishings.