The building
Contenido
Para llevar a la práctica estos puntos, el estudio holandés creó cinco plataformas, cinco clústers "Cluster (informática)") con programa y equipamiento específico para las actividades a desarrollar en cada uno de ellas. Estas plataformas se materializarían en volúmenes colocados uno encima del otro, dejando espacios intersticiales entre ellos que estarían dedicados a la lectura, el trabajo y el reposo. Los volúmenes apilados estarían desplazados de forma aleatoria respecto a la vertical.
Hacia el exterior se buscó la relación de la biblioteca con distintos hitos de la geografía de Seattle: hacia el Mount Rainier, Elliott Bay y la Interestatal 5. Se buscó una estética particular, con una fachada de vidrio y acero a base de superficies facetadas que contrastasen con los edificios adyacentes a la biblioteca, y generando un nuevo icono urbano. OMA citó en la memoria del proyecto de diciembre de 1999 la fachada de pliegues del Experience Music Project de Frank Gehry, situado también en Seattle, como icono del desarrollo de la moderna Seattle, junto a la nueva Biblioteca Central.[5].
También se le dio una especial importancia al acceso virtual a la biblioteca a partir de internet. Según la memoria de diciembre de 1999, los espacios virtuales y reales de la biblioteca fueron concebidos en paralelo, como parte de la misma arquitectura. Las plataformas en las que se diseñó el edificio se repitieron en la organización del sitio web de la biblioteca, y las estrategias de comunicación que proveían acceso al espacio de la biblioteca tuvieron su reflejo en la plataforma virtual de la institución en internet.[5].
Interior organization
The interior organization of the building is based on the grouping of the program into five platforms. Among them are consultation spaces, reading and leisure areas; and on the last of them, on the roof of the building, there is a terrace with views over the city. The final floor plans and sections of the building can be consulted in Floor Plans for the Central Library (in English). The size of the Library and its interior configuration can cause visitors to get lost; For this reason, at the entrance from Fourth Avenue you can pick up a map detailing the interior route itinerary.[6].
Due to the unevenness between the different streets that surround the building, there are different entrances at different levels for each area of the building.[7] The interior distribution of the building can be described from the platforms that make it up, as follows:
• - The platform on which the building sits is made up of the so-called operations area and the 143-space parking lot in the second basement, accessible from Spring Street. The operations area is located in the first basement and is made up of the service spaces for the operation of the library: warehouses, photocopiers and security. The Faye G. Allen Center for Children is located on this platform: a 1,400-square-meter space that has a collection of 80,000 books, DVDs and CDs and 22 computers; as well as the Microsoft Auditorium, a small room with 275 seats that can be expanded with another 150 and which is accessible from the ground floor. This floor is accessible from Fourth Avenue, while three elevators and a freight elevator connect all floors of the building and constitute the backbone of the building.
• - The second platform is made up of a first service level, which contains various spaces for personnel and the loading platform for trucks. Above this level is the area called living room, which is one of the main spaces of the building with a free height of 15 meters and is accessible from Fifth Avenue. Within it there are rest and meeting areas, points for consultation, withdrawal and loan of books, a cafeteria, a shop and the Maria Lee Koh and Family Fiction Collection. There is also direct access to the Microsoft Auditorium and a patio that serves as an intermediate space between the interior of the building and Fifth Avenue.
• - The third platform is made up of everything related to technology: on the first level called assembly are the computer laboratories and two Boeing Technology Learning Centers, as well as four meeting rooms. Above them is the area called mixing room, a space of 1,800 square meters with a total of 145 computers that is made up of meeting areas, public computer stations for information and search, and other stations with computers for learning computer science. Also located in the mixing room is the main point of information and search for books by reference.
• - The fourth platform is made up of one of the main and most innovative spaces of the building, called the spiral of books. It is formed by a ramp that ascends in a spiral with a gentle 2% slope along the four floors it occupies. This ramp organizes the space around it, and allows access to the rows of book shelves, organized according to the Dewey Classification System. Each floor of the spiral of books corresponds to a different subject, so that the books of each subject are gathered and organized in a single space, avoiding the common dispersion in other libraries. There is also an escalator that connects the different floors of the spiral, avoiding the need to take the entire route to access books already placed. Above this space is the double-height main reading room.
• - The fifth platform corresponds to the administration and management spaces of the Seattle Public Library System. It is made up of two floors of offices and spaces to store some of the government publications. On this floor plan, which looks towards Mount Rainier, is the roof of the building, which in the project was intended to be used as an outdoor terrace.
Structure
The Central Library was designed through a series of innovative structural solutions, which emphasized the floating platforms effect with which the building was designed and allowed it to withstand the risk of earthquakes in the Seattle region. The engineering consultancy Magnusson Klemencic Associates "designed the structure, supported by the prestigious firm Arup and partners in the preliminary phases of the project. To this end, a complex structure composed of steel pillars, mixed slabs and deep trusses was chosen to support the cantilevers and allow large spans "Light (engineering)") that would reduce the number of pillars necessary to support the structure inside. The elevator core was used as a structural screen "Screen (containment structure)") that held the steel structure against the risk of earthquakes.
The structural design of the Seattle Central Library was awarded by the American Council of Engineering Companies (ACEC), which awarded its "Platinum Award" in 2005 to the structural solutions used in the Library.[8].
Facade
One of the fundamental aspects of the building's design was that it be as open to the public as possible. On the façade, this conceptual feature required that the interior of the building and its distribution could be seen from the outside both day and night, and that the interior spaces received the greatest amount of natural light possible. For this reason, a continuous curtain wall façade was chosen that would unify the different faceted surfaces that composed it.
The façade is made up of triple glazing made up of pieces of glass 1.2 meters long by 2.1 meters high and cut in a diamond shape. Several solutions were studied to prevent the entry of excessive natural light and heat due to solar radiation in those parts of the façade facing south, and finally it was decided to introduce an expanded aluminum mesh inside the glazing in those areas where it was necessary. Approximately half of the total façade surface has this solution.[9].
The rest of the glazing has an architecture based on layers with strong joints that allow the façade to withstand the forces due to wind, rain and the entry of air into the interior. This type of glazing solution and the use of mesh to solve sunlight problems are common in commercial and office buildings in Europe, although the Seattle Central Library was the first building in the United States to use this type of solution on its façade.[9].
Finishes
The Central Library has a series of different finishes depending on the floor and its intended use, in order to emphasize the design based on suspended platforms.
The entrance through Fourth Avenue leads to a space with pavement based on brown polyurethane. The elevator core is covered by aluminum panels; The pillars and ceilings are finished in polished exposed concrete. The quartz luminaires are suspended from the ceiling throughout the entire floor, creating a plane of light throughout the entire floor space.[10].
The Faye G. Allen Center for Children, which is located north of the Fourth Avenue entrance, has a natural bamboo floor; Two areas are paved with rubber painted pink and yellow, and the color extends to the walls. These colored areas are spaces for reading, pink for toddlers and yellow for children ages five and up.[10].
The Anne Marie Gault History Room, a triangular space covered in green, has vertical perforated wood partitions. On the ceiling, the luminaires are arranged randomly simulating the pattern of stars, and a large skylight and doors located at the ends of the room introduce natural light into the interior.[10].
The Evelyn W. Foster Learning Center is home to the collection of English as a Second Language and World Languages books. The floor of the room is a maple parquet created by the artist Ann Hamilton"), which includes 566 lines of text written in eleven languages and alphabets of the world, written backwards and that were extracted from the first five sentences of several books in the collection.[10].
This level, which is called assembly, has six meeting spaces of different shapes. The ceilings, walls and floors of the hallways and common spaces of the entire level are covered in different shades of red. However, the interior of the meeting rooms and laboratories is treated with neutral materials and colors that promote concentration and learning. From this level you can see the living room on the lower level through a curtain wall that visually connects both levels.[10].
The Mixing Room has a continuous aluminum floor. The columns, painted black, and the roof are protected against fire and covered with a transparent sealant containing mica chips.[10].
Books are the fundamental part of any library. For this reason, the Spiral of books was designed with simple finishes that left all the prominence to the books housed on its shelves. The floor is finished in exposed concrete, and numbered carpets are interspersed according to the Dewey Classification System that correspond to the adjacent shelves. The ceilings are covered by transparent polycarbonate panels and fluorescent lighting.[10].
Indoor and outdoor vegetation
The Seattle Central Library's exterior greenery was designed to be environmentally friendly and require as little maintenance as possible. Approximately a quarter of the plants used on the exterior of the building are drought tolerant.[11] A water-efficient drip irrigation system was installed that whenever possible would use water from a 150 cubic meter collection tank of rainwater collected from the building itself.[11]
Trees of eighteen different species were planted around the Library, including magnolia, sweetgum, birch, oak, maple "Acer (botany)") and different types of tulip trees; Two trees were rescued from the garden of the old building and were replanted near the new fountain built on Fourth Avenue.[11].
Different types of grass (acorus calamus, sesleria, molinia caerulea, hakonechloa, deschampsia, elymus, festuca, carex and uncinia), ferns (adiantum, blechnum spicant, dryopteris erythrosora") and polystichum munitum) were planted in the flowerbeds. perennial flowers (liatris, hosta, iris sibirica and tradescantia).[11].
As for the interior vegetation, microsorum, asplenium and philodendron were planted in the living room on level three.[11].
Sustainability
In the design of the Seattle Central Library, certain aspects were taken into account to reduce energy consumption and the environmental impact of the building. These aspects were:[12].
Erosion and sedimentation control was carried out on the library site during construction. In addition, the plot is located near a bus stop and a bicycle parking lot was created to encourage the use of public or non-polluting means of transportation. The vegetation that was placed on the exterior of the building was designed to try to reduce the heat island effect and minimize water consumption. The rainwater collected in the building would be used to irrigate the vegetation. Water use inside the building was reduced by the use of efficient mechanical equipment, and exterior luminaires were designed and automated to reduce light pollution.[12].
The building was designed to exceed Seattle's energy savings code by 10%. Approximately half of the glass used in the facade curtain wall consisted of triple glazing with expanded aluminum mesh to reduce heating due to solar radiation inside the building. Air movement inside was automated to maximize energy efficiency. No chlorofluorocarbon-based refrigerants were used in the air conditioning system. Nor were haloalkane gases used in the fire protection system, control systems, air conditioning, water use or energy performance improvement systems.[12].
A space was designed in the building to store and select recyclable materials. More than 75% of the waste produced after demolition and subsequent construction was recycled, and a significant part of the recycled material was used in construction. At least 20% of the products used in the construction of the new building were manufactured in a 500-mile area around Seattle, thus helping the local economy and lessening the impact of long-distance transportation.[12].
The Central Library exceeded the standards set by Law 62-1999 of the North American Society of Engineers for heating, refrigeration and air conditioning, regarding acceptable indoor air quality. Smoking is not allowed in the building, and carbon dioxide is controlled so that it does not exceed 530 parts per million compared to outside air. During construction, a plan was implemented to control air quality inside the site by protecting porous materials from moisture, replacing building filters immediately prior to building occupancy, and carrying out a two-week process with the new filters to clean the HVAC system of outside air. The carpets were chosen with a low emission rate of polluting substances; An automated system was designed to regulate thermal comfort inside; and the entry of natural light was maximized: 90% of the regularly occupied spaces have natural lighting.[12].
The project relied on the advice of an acoustic engineer to recommend design elements that would improve occupant comfort, and used a high level of recycled materials, according to OMA's project report. LEEDTM is the US Green Building Council's system for measuring the degree of sustainability of a building project in the United States. One of the authors of the Seattle Central Library project was a LEEDTM-accredited professional, which helped adapt the building to the system's standards. Work was also done to include a section on the institution's website dedicated to the building's sustainability-related features,[13] and to offer tours of the building focused on the sustainable aspects of the project and LEEDTM.[12] The Seattle Central Library eventually obtained LEEDTM silver certification.[14].