An innovative system of insulated glass encloses the Central Library. On surfaces of the building that receive the most sunlight, an expanded metal mesh layer within the glass reduces heat and glare, while retaining visibility.
A key concept of the building's design was that it be transparent and open. The building is covered in glass to allow passers-by to see the different parts of the building - such as the Books Spiral - and what is going on inside.
The visibility of the building's interior and the appearance of the exterior varies with the lighting conditions outside - whether it's clear and sunny, overcast, or it's nighttime.
The exterior glass, cut in approximately 4-foot by 7-foot diamond-shaped units, promotes energy efficiency by letting in natural light and reducing the need for artificial light.
After considerable study, metal mesh glass was selected for those surfaces receiving direct sun. The metal mesh - aluminum sheet metal that is cut and stretched and placed between layers of glass - is used on approximately half the building exterior. It reduces glare and heat.
The rest of the building skin is comprised of clear glass. All the glass includes coatings to help improve energy performance. The glass assembly is very strong. It passed all wind, rain and air infiltration tests and met all codes for earthquake resistance.
Such glass units are used on many office and commercial buildings. The metal mesh inserted in the glass units has been used in Europe, but the library was the first building in the United States to use the insulated glass.
Building form designed to control light
The building was designed to control the type and quantity of sunlight. Library program areas were placed where they would receive appropriate light. The Norcliffe Foundation Living Room, for example, faces south, which means the room is filled with daylight, filtered by the metal mesh layer. The Betty Jane Narver Reading Room, however, faces north and it has more controlled light with less glare, which is more conducive to reading.
The glass is cleaned twice a year, or more often for surfaces that need it. Window washers use attachment points on the building's exterior to help them get around the building efficiently.
Storm water running off the building is stored and used for irrigating the landscape around the building.