Quay rebirth.

Renovation and conversion of a quayside warehouse in Antwerp provides civilized offices and an airy rooftop flat.

Antwerp is presently undergoing something of a renaissance. New law courts by the Richard Rogers Partnership are planned for the south-west end of Amerikalei, the arterial boulevard bisecting the city, and RRP has been asked to prepare a masterplan to regenerate the immediate area. In the old -- and still active -- docklands, redundant buildings are gradually being converted into desirable dwellings, elegant eating places and shops. The harbours are still picturesque with waiting barges and dockside activities and, with its mixture of the commercial and residential, the place is an agreeable one in which to live and work.

Jo Crepain's sensitive metamorphosis of an empty quayside warehouse into a flat (for himself and his wife) and offices (for the practice) succeeds his delightful conversion of an old watertower into a woodland house for one person (AR December 1998). In both cases, while respecting architectural character, he has employed cool rationality and a tough industrial vocabulary to open up the building and create extraordinarily austere light-filled spaces.

In Antwerp, offices fill the lower levels of the warehouse. The flat above them is on two floors with sleeping quarters on the third and living room in a rooftop extension. Externally clad with gleaming aluminium panels, the extension is open to the sky and surrounding roofs with the spire of Antwerp cathedral silhouetted in the distance.

Dating from about 1910, the warehouse is an 11x2Om rectangle on plan and faces north onto the street, with boundary walls on the south and west. To the east was a '30s office building and a warehouse of no interest. These were taken down to create a courtyard shaded by trees and giving access to the offices and the flat above them.

The brick face of the building, with its stone dressings, was restored; modern openings were suppressed and original windows bricked up in the east wall were reinstated and the exterior rendered grey to match the back wall. Inside, the handsome structure with cast iron columns and jack arches was cleaned and repaired. The main structural insertion is a black lacquered concrete shaft that rises through the building and shoots through the roof to contain a service unit. Built between the columns and replacing the old industrial lift in the southern half of the warehouse, the shaft contains a new lift and the staircase.

On the office floors, volumes are open but can be divided up by means of large sliding doors. On the third floor, Crepain slides private rooms off to each end of the building-the master bedroom and bathroom to the south, a guest room and study to the north -- leaving a big open space (described as multifunctional) in the middle. A similar but more open arrangement prevails above with a dining room and kitchen at one end, library on the other, and living room in between. Here, space expands and is flooded with light from three directions for the extension, really a rooftop pavilion, is double height with clerestorey windows on north and south running the width of the building. On the west, the living room is partly invaded by a large terrace, and barely divided from it by glass walls so division between inside and outside is blurred.

Whereas on the lower floor, Crepain has allowed the original warehouse structure and plain woodblock floor to lend character to space, here the vocabulary is of raw concrete (for ceiling and walls), aluminium and glass. The coarse texture of beton brut is counterpoised to the silky surface of aluminium kitchen fittings and gleaming expanse of woodblock floor. Dove grey concrete under changing light is the austere background for the inhabitants' collection of modern art which stands out in vivid relief.