King Fahad National Library, Riyadh, Saudi Arabia

With its striking geometric form, the new square addition to the King Fahad National Library in Riyadh envelops the original 1970s building and stands in sharp contrast to the surrounding heterogeneous urban landscape.

Situated in the middle of one of the city's parks, the new library appears open and transparent, and, despite its size, is incorporated into the urban environment in a graceful manner.

It forms a square 'ring' around the older building, creating an architectural unity together with the new structure. The flat roof of the older building serves as a reading hall, while the book stacks are located in its core, not unlike a treasure chest. Visitors reach the open-access area, which is located on the third floor of the new building, via bridges.

The existing dome is redesigned as a steel and glass construction and towers above the new roof, which also covers the interior courtyards and the reading hall. A white membrane, suspended beneath the roof, filters the sunlight through long skylights and provides all rooms with an even, glare-free light.

At night, lights above the membrane, which serves as a kind of 'light roof', assume this function. Separated from all other areas is the women's library, located in the first storey of the new southwest wing.

BLENDING OLD AND NEW

The façade of the new building is composed of an interior glass façade supported by ceilings of reinforced concrete and an external layer of suspended white membrane surfaces, held by a three-dimensional tensile strain steel cable construction, that serves as a sunshield in the upper-storey façades.

The steel guy cables are mounted onto the floor ceilings by means of horizontal cantilevered steel pressured tubes that absorb the ensuing horizontal forces. Diagonal steel struts ensure the necessary bracing of the protruding structure. The sails, made of slightly translucent fibreglass, give 90% protection from direct sunlight to the building's interior.

The view into the upper part of the building as seen from the plaza remains unchanged and the views from inside out are also preserved to ensure a maximum level of transparency.

By combining the old and the new, a unified and formal architectural image with a characteristic design is created. At night the façade shines in changing colours, transforming it into a cultural beacon lighting up the city.

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