Abstracting materiality.

A garden shed is the unlikely focus for an exquisitely sensitive exploration of the nature of brick and concrete and their tectronic relationships revealed in space and light.

Carl-Viggo Holmebakk's addition of a secluded library to his parents' house in Oslo (AR August 1996) has been followed by the construction of a garden shed and workshop to the north of the house. There was very little space in the wooded garden on which to build because of a general desire to keep all the trees.

The expected lean-to has become a cylindrical tower of brick, three storeys high, surmounted by an oversailing arcing canopy of wood and fibreglass, practically and poetically designed to shed rain and snow. Robustly articulated, the structure expresses the functional traditions of the workshop and Scandinavian regard for material honesty.

Exploiting the inherent structural strength of the cylindrical form, Holmebakk has built a single skin of brick 6.5m high. The bricks are laid in stretcher bond with wide joints to accommodate the curve. Stretcher bond rarely looks good, but here it emphasises the building's circularity and adds complementary texture to an essentially smooth geometrical form.

A pair of pine doors let into the base of the tower follows the coursing and curve of the brickwork. Holmebakk's purism and attention to detail precluded cutting the brick to obtain a door frame. Instead, he allowed alternate courses of brick to project as tusks on the sides of the opening. Horizontal members of each door fit between the tusks and the doors move on pivots so that when they are closed, they seem to bon into the wall.

Inside the tower, Holmebakk has drawn on the vocabulary of the workshop and natural daylight. With his own hands, he has put together a two-storey wooden structure suspended from two laminated beams fixed to the upper rim. Attached to a spiral staircase of galvanised steel, the inner structure consists of slatted platforms, shelving, worktops and benches. Light filters down through the translucent roof through the floor slats and down the sides of the enclosing wall, for the timber is independent of the brick skin and leaves the ground floor clear for storing tools and garden implements.

The little tower with its simple form and floating canopy evokes the Danish medieval military architecture of south Norway, or a mysterious Neo-Classical structure of the early Industrial Revolution; it has the kind of delight given by the miniature offspring - the lodges and garden structures - of great houses. But this building is unique; a simple clearly expressed structure, it is the product of sophisticated thought and craftsmanship.