Changing rooms.

A re-use in which new inner construction is articulated with elegant tectonic skill.

Randy Brown's house and studio, in Omaha, Nebraska, were created within the walls of a square (40 x 40ft; 12.2m x 12.2m) two-storey structure on one of the city's main streets. Opposite is the University of Nebraska. The building was constructed in the '70s as an infant school and designed as a passive solar structure, with tall south-facing windows, sunshades, and hot air ducting under the concrete floor. When acquired by the Browns it was sadly dilapidated.

Having repaired the structure, glazed the south facade at two levels and fitted modern solar shading, Brown stripped out the interior of the building to create a double-height white painted shell. The existing concrete floor was simply sealed. Working to a limited budget, he dealt with the amorphous space by establishing a series of different zones on either side of a central core.

This structure is an ingenious and dynamic invention bristling with projecting timber, haphazardly angled planes, flying pieces of metal and odd pieces salvaged from junkyards, visibly assembled with screws and brackets from the local hardware store. The scheme is partly intended as a practical demonstration for clients of how buildings are put together from simple components; junctions are made explicit, plumbing and fixings left exposed.

Taken all together, the eccentric assembly has method behind it, and an elegantly Constructivist air that is continually pleasing. It can apparently be easily. It can apparently be easily dismantled with a screwdriver and wrenches: one of the architects' central concerns seems to have been to create a series of environments capable of change.

A studio for the practice occupies a shallow plinth running parallel to the south wall; an inner zone is devoted to the living area, and this in turn gives onto a service area where the kitchen, bathroom and utility room are set in a row along the back north wall.

A wide arc cut into the plinth contains the curving wall of the core structure which rises to first floor level to create a bedroom gallery. On the ground floor it encloses a dining/conference room within a structural collage of bookcases, cupboards and timber columns.

Everything has been imaginatively thought out. A steel and glass table rests on castors at one end and, set on a roller at the other, it protrudes into the living area through a slot in a big curved stainless steel shelving unit hung over the edge of the gallery. The table can be slid backwards and forwards depending on how much of it is required on either side.

In similarly thoughtful manner, the metal unit (outwardly smooth and convex, inwardly concave to take shelving) rises into the sleeping gallery to provide storage in the bedroom as well as in the conference space. More storage is generated by wooden cupboards projecting over the side of the gallery beside the staircase. From the sleeping gallery, another flight takes you onto the roof. Brown has plans to extend the building here.

Throughout the work of designing and building the scheme, Brown has been at pains to show how you can salvage and use what exists, and in the process make imaginative use of a redundant building.