This project is our response to an open international design competition for a new public library in Daegu, a city of two million in South Korea. We used this competition as a platform to explore two enduring interests – the relationship of structural systems to form, and the developing typology of the modern public library.

The site is within the dense urban context of the Gosan district of Daegu. The library is located to the south end of the site in order to leave the north end, which is contiguous with a public park, open as public space. This open space runs across the entire north end of the site and expands to the east at the entry to the library.

A ‘parking court’ is located within this open space, extending an existing line of parking which runs along the south edge of the park to the west. Gates at either end of the public space transform the ‘parking court’ into an enlarged ‘event space’ for community celebrations and occasions, such as a used book fair, a children’s festival, or a community barbeque.

Upon entering the library, the community of library users unfolds before you; the main reading area forms a terrace immediately ahead, while the lecture hall falls off in a slope to your right, the library reception edges the space and the long circulation counter/new books wall guides you to the smaller children’s terrace tucked under the main reading terrace above.

We conceived of the program as a continuous topography rather than a series of discrete boxes. This offers visitors a range of choices, to accommodate the widest range of individual preferences in terms of space and social engagement. The library is organized on 4 levels which are connected by a series of reading terraces. The main reading terrace connects the entry level containing lobby, circulation desk, back-of-house services, and an auditorium to the collections level above. Within this larger seating terrace, the round pods afford smaller, more intimate pockets. A secondary reading terrace continues the upward path to the digital media lab tucked up under the roof form. Moving down from the entry level, the children’s performance, story-telling, and reading terrace connects to the children’s library and a suite of community services and culture rooms below.

The library can be divided. A garden court to the northwest leads to a separate community entrance. During hours when the library is closed, this entrance gives access to the lower entrance lobby and to the suite of community rooms. An operable glass wall separates the lecture hall from the library at the main level entrance lobby. The children’s library simply locks its doors. The library becomes a community cultural center with extended hours of use for events and rental opportunities. By connecting and ‘bundling’ program elements of varying scales, we can maximize their combined value. These connections are established by carefully crafting spaces for large events as well as providing for smaller ones by use of critically placed separations and joints.

The structure of the library comprises reinforced concrete floor slabs supported on reinforced concrete columns and walls. The exterior walls and roof are supported by a timber shell. This shell has material, structural, and formal virtues. It is made from wood, the only renewable structural material, in straight lengths and conventional sizes – staggered 16 ft lengths of 4 x 8” and 4 x 14” timber, connected by 2 ft lengths of blocking to form a reciprocal frame – sheathed by 3 layers of half-inch plywood.

We used Grasshopper to generate a parametric model of the entire building enclosure. This model included the timber shell of small, easily handled structural members, the various envelope layers using standard sheathing panel sizes, and a complex exterior surface tiled with a single repeating shape. It saved significant effort in both modelling and structural analyses, allowing us to investigate numerous variations of the complex and evocative forms that this structural system can accommodate. This level of design study would not have otherwise been practical in the time available.

The timber members rotate slowly across arcs which describe the vertices of the building to create generous curvilinear forms. The resulting ‘ruled surface’ form acts monolithically as a shell structure to greatly enhance the structural performance of the timber and plywood assembly. Sections of the shell would be prefabricated into six-foot wide panels of varying length, filled with high-pressure spray-applied polyurethane insulation, clad with a self-adhering, self-sealing waterproof membrane, and then assembled on site. The exterior surface of the shell is to be covered in situ with two inches of architectural ‘shotcrete’, a secondary waterproof and anti-crack isolation membrane, and finished with ceramic tile.

Research