San Francisco Federal Building
Christine Atienza mauro cardenas lisa gallego don love nate mendelsohn
cal poly san luis obispo barry williams studio arch 481/492, fall 2008
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general information
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Summary hypothesis
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Detailed Hypothesis
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site plan
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Lobby floor plan
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Typical Office floor plan
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perspective vignettes
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vertical section
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building systems matrix
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section detail
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systems
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SIMULATION OF PERFORMANCE
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final model
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Final Poster
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Table of contents
introduction
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introduction A case study is an intensive analysis of an individual unit (as a person or community) stressing developmental factors in relation to environment. A precedent is something of significance. Rather than researching a collection of smaller variables the case study method involves an in-depth, longitudinal examination of a single set of criteria designed for a specific purpose: it sets a case. The case we are researching is that of the tectonic response to the program. This project investigates building system responses to specific criteria. The case study provides a systematic way of looking at architectural solutions based on known criteria. As a result, the researcher may gain a sharpened understanding of why a particular solution was proposed. Case studies often lend themselves to both generating and testing hypotheses. The intent of the problem is to gain an in-depth understanding of how an architectural project relates to a set of criteria. An in-depth study of the architects’ use of the various building systems and their integration with one another will help the student be able to understand the reasons that specific a set of criteria were used. With this knowledge we can gain a better understanding of systems and their selection for incorporation into our own thesis projects. The main focus of this project is the construction of a large scale physical model of a key section of the facility.
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office building
general information
fac i l i t y ty p e l o c at i o n a three-acre site adjacent to the historic 1905 u.s. court of appeals at the corner of seventh and mission streets in the south-of-market neighborhood.
c l i en t general services administration
c o m p l etion d ate spring 2006
size tower: 500,000 gsf, 18-stories, 240’ high annex: 105,000 gsf, 4-stories, 60’ high
p a rki ng 47 spaces for tenant agency use
m aj o r b u ild in g comp on e nts Health and Human Services, Department of Labor, Social Security Administration, Department of Agriculture, Department of Defense, Rentable Space
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dversely affects the local climate of urban also been an eyesore for local businesses
over 13% of the total value of construction r post-industrial waste. uction waste was diverted from landfill 3 million in potential dumping fees. n the building will come from renewable
Building, tower behind / © Steve Rhodes tower federal building,
behind.
Source: Steve Rhodes.
es, the building employs a ing system that operates vel vents in the building he system maintains comfortytime temperatures and can building’s thermal mass at offset daytime heat gain.
erage daily temperatures from 49 to 65 degrees degrees Celsius) in San o, natural ventilation can on the building for nine of the year. From mid-April October, the natural ventilatem will cool the building. h and November, the building ntain sufficiently warm temperatures with the winosed. In December, January, ruary, linear steam-source ors incorporated into the -wall mullion system will n thermal comfort.
The building’s “living skin” has generated remarkable energy and financial savings. The GSA requires its new buildings to use less than 55 kBtu of energy per square foot (170 kWh per square meter), in an effort to reduce their 69 kBtu-persquare-foot (220 kWh-per-squaremeter) portfolio average. The San Francisco Federal Building is projected to use only 37 kBtu per square foot (120 kWh per square meter)! This energy savings translates to US$500,000 per year in operational savings. Also, elimination of a mechanical cooling system in the building’s tower saved US$11 million dollars in construction costs. These savings justified investment in the southeast façade’s perforated metal scrim. The metal “second skin” is not only vital to the building’s energy efficiency, but also defines the exterior aesthetic.
interior lobby. green-building ed, tried-and-true Source: Tim Griffith. d material efficiencies. It proves how a 10 lth and livelihoods not only within the
According to Thom Mayne, the San Francisco Federal Building is a result of a series of questions that focused on implementing three ideas: • • •
Maximizing community engagement and involvement Creating a healthier, more creative work environment Creating a sustainable and energy efficient model
With the design of the SF Federal Building, Morphosis attempted to create a new green center for the government in consolidating multiple offices into one space. The structure is sited south of Market Street, a less desirable section of town, in a bold statement of resistance. With huge concrete columns supporting a layered, perforated metal skin, the building has a hulking yet gentle presence that has set a new precedent for the face of city towers. The site itself is long and slender allowing the building to maximize natural airflow by incorporating operable windows on the north and south facades behind the skin, which are controlled by users and computers. The steel skin sits away from the windows on the south face, allowing air to flow around it. It acts like a giant heat sink, absorbing and dispelling heat. The shape of the site also led to the design of a slim building with open office floor plans that could be naturally lit. The plans and skip-stop elevators force people to use the stairs and public areas in an attempt to improve communications and intra-office relationships. After using the spaces, however, employees have begun to complain that there is not enough control over individual environments. Strong San Francisco winds blow papers all over the office when windows are open and it is nearly impossible to create a stable temperature. These passive systems are backed by an under-floor ventilation system that uses the entire plenum for air movement instead of through ducting. A problem arose in construction when workers could not get the plenums to seal and pressurize to the correct levels, an issue which is still being dealt with today. The primary goal of this space was consolidation and improved efficiency of governmental processes, but with uncomfortable users the task is not complete.
Summary hypothesis
Usage
At the street level, the building’s skin hovers above an open plaza welcoming the public into the building while retaining a very solemn and secure face. A gentle sloping lawn in front of the lobby is actually a blast wall in disguise. In the event of a horrific attack, the wall is designed to deflect a blast up and over the children’s day care center. Security cameras hang neatly from the skin’s frame watching your every move. No one is able to enter the space without proper security clearance. The Federal Building is a government building, but with a whole new look.
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Building Type: Recognition Status: Completion Date: Gross Square Footage: Total Project Cost: Energy Cost Savings: Site Energy Use: Site Energy Use (floors 6-18): DOE Climate Zone:
Office high-rise Pursuing LEED for New Construction v2.2 Silver 2007 605,000 sq. ft. (56,200 sq. m.); 18 stories US$144 million US$500,000/yr projected 37 kBtu/sq. ft./yr (120 kWh/sq. m./yr) projected 28 kBtu/sq. ft./yr (88 kWh/sq. m./yr) projected Zone 3 (3200 HDD, 70 CDD)
Exterior building fa © Rocky Mountain
for the intelligent use of natural PROJECT OVERVIEW resources. Significant energy savings The San Francisco Federal Building were achieved through the collaborawas designed to meet the “highest tive work of an expert design team. possible standards of performance The Lawrence Berkeley National and aesthetic integrity.” Three major Laboratory modeled natural ventilaobjectives target this goal. First, the tion; Pritzker Prize-winning architect, 60-foot-wide, 354-foot-long, 234Thom Mayne, and his firm Morphosis foot-high tower (18m x 108m x 71m), generated the architectural and with its translucent, undulating skin urban design concepts; Horton Lees and progressive urban design strateBrogden designed the natural and gies, is intended to serve as a new artificial lighting; and Ove Arup prourban landmark for the City of San vided structural and MEP (mechaniFrancisco. Second, the building intecal, electrical, and plumbing) engirior was designed to be a model neering. The building includes an workplace. Natural ventilation, inno18-story office tower with three-story vative common spaces, and flexible elevator atrium-lobbies and an outfloor plans foster health, productivisunscreen panel framing and panels. The use of BIM affords great to large scale projects, both quantitative and qualitative. For door example,“sky garden;” a low-rise public ty, benefi andts creativity. Third, the building the ease of translation between software platforms has greatly reduced time in preparation and checking of source: morphosis. shop drawings. Estimators are able to operate cost modeling with a higher degree of accuracy. And many office, daycare, and café wing; and was envisioned as a benchmark laborious negotiations over fine-grained performance details can be greatly condensed, with all parties providing simultaneous review of the digital model. Key to the success of this is the willingness of both a large public plaza. design and detailing team members to expose their models to scrutiny. At this stage, accurate quantification of benefits remains highly elusive as new relationships are forged between designers and fabricators. We encourage the construction industry to begin detailed analysis of the cost benefits that may accrue to the process: estimating, detailing, and scheduling. Open dialogue between all parties can move the discussion to a more sophisticated level and allow a predictive framework to emerge.
THE BOTTOM LINE The General Services Administration Morphosis employs Bentley Microstation as its cad platform, and Bentley Triforma and Bentley Structural (GSA), the federal government’s for BIM. B.D.S. creates parametric steel detail models in Tekla Xsteel, and Permasteelisa utlizes Autodesk Autocad for detailing, unfolding and drawing the perforated metal. The SDNF file format was used to exchange land ownership and property manround-trip between Morphosis and B.D.S., and DWG format was used to exchange round-trip between Morphosis, B.D.S. and Permasteeelisa. This seamless digital round-trip meant that there were very few areas agement arm, will operate the San where the layout geometry was in question, and at the end of shop drawing review, there were no areas of the detail models which diverged from the intended design geometry more than a few millimeters. Francisco Federal Building for its entire lifespan. Fiscal responsibility over Panels long-term ownership provided Layers of trades: Structural Primary Frame, Secondary Steel, Sunscreen Panel Framing, Sunscreen a strong incentive for the inclusion of high-performance building features. Seventy percent of the buildLiving Skin. Living skin facilitates natural ventilation ing is naturally ventilated, which © institute. Rocky Mountain Institute Source: Rocky Mountain
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saved approximat in construction co ventilation system to save half a mill year and reduce c costs by 86 perce decreasing constr tion costs, natura daylighting, and o amenities are exp worker productivi even greater long Open office plans employee interac the flexibility to in accommodate cha mental workspace Federal Building i of the attitude tha strategies are inte high-quality, aest nent, and cost-eff
“What’s driv
fundamental
superior wor
federal work
for the taxpa
— Kevin Kampsc Director of Exp Public Buildin
The building itself had a strictly defined program, so the client and Architect implemented the idea of ditching the typical office to improve the quality of the workplace. The typical office plan was left open to promote interaction. There are no edge offices; instead they are placed in the core of the plan, allowing almost all of the workers to take advantage of the urban view of San Francisco and the bay to the Southeast, and Downtown San Francisco and the Civic Center to the Northwest. The Federal Building also concentrates offices city wide into a central location.
solution The federal building uses seventy-five percent recycled materials, which includes replacing a percentage of Portland cement with blast furnace slag in the concrete. This results in stronger concrete. The concrete slab’s thermal mass is used to retain cooler air during the warmer summer days. The undulating form of the slabs also reduces the use of materials while promoting natural ventilation throughout the building. From the sixth floor and above, the building’s interior temperature is controlled by means of natural ventilation. A computer automated system controls a number of the windows, while many remain manu al l y op e r ab l e b y th e u se r . Th e or i e ntation of the building takes advantage of a reliable Northwestern prevailing wind during the summer. Also, furniture is raised eighteen inches off the ground and the core offices are detached two feet from the ceiling to allow fresh air to travel from end to end.
c o nt e x t
Detailed Hypothesis
p ro g r a m
The design team approached the community in a contextual manner. The process launched after more than fifty meetings with users, clients, and city officials. The building sits on the intersection of Mission and Seventh Streets, half a block away from the civic center. The development of this site hopes to bring in a flood of new offices and retail spaces to the impoverished neighborhood. The 1800 workers also contribute to local restaurants and shops. The design team wanted to engage the community through the use of the urban plaza, public cafĂŠ, sky garden, c hild ca r e cen ter . A ll of th e s e ame n i ti e s ar e made avai l ab l e fo r th e pu b l i c.
o r g an i zation In order to promote a healthier human environment, Thom Mayne implemented the use of skip-stop elevators, which stop at every three floors. The elevator opens to a secondary lobby that promotes interaction and communication among workers, while a seamless window at the staircase landing frames views of the city. The secondary lobbies are clad with a folding wood veneer, which creates a warm, inviting environment.
Lighting The biggest design factor was the building skin, which not only gives the aesthetics of the building, but promotes the idea of resource management in the creation of a sustainable and energy efficient model. The Northeast skin consists of frosted glass fins which block out summer sun while guiding winds into the building. The Southwest skin is a semi-transparent layer of perforated metal that wraps over the top of the building, onto its side, and over the day care and plaza. This skin blocks 50% of the sun rays while allowing light to filter through and naturally illuminate the work spaces.
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mission street
market street
7th street
6th street
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site plan
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0’
32’
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Lobby floor plan
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0’
32’
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Typical Office floor plan
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perspective vignettes
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vertical section
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building systems matrix
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section detail
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Drilled piles with pile cap load transfer to primary concrete shear walls
s t ru c t u ral s y s te ms
systems
fo u nd a tion
tower: concrete shear wall system, wave slab with upturned beams annex: steel structure with special moment frame in east-west direction, concentric braced frame in north-south direction Child care and pavilion: moment frames scrim support: tube steel and built up beams with bolted connections
m e c h an ic al s y s te ms central plant: centrifugal chillers with cooling towers, steam purchased from local utility annex, child care, fitness center, and lobby: variable-air-volume system with economizers tower, conference center, and levels 2-5 office areas: underfloor displacement ventilation system with economizers tower, levels 6-18 perimeter areas: natural ventilation cooling with finned tube convector heating elements tower, levels 6-18 enclosed cabins: water source heat pumps with waterside economizer
e l ec t r i c al s y s te ms busbar distribution system with dedicated bus for mechanical equipment; panel-level monitoring of energy use; daylight harvesting; emergency generator for life-safety elements and server shutdown
fi ni s h e s exterior: perforated stainless steel sunscreen panels, exposed concrete, galvanized steel, anodized aluminum and glass window wall public areas: polished concrete floors, exposed concrete walls, perforated maple panels, glass, fiber cement board, venetian plaster offices: concrete, carpet, painted gypsum board, glass
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STRUCTURE
ENVELOPE
INTERIOR
MECHANICAL SYSTEMS
SIMULATION OF PERFORMANCE
The form, structure and orientation of the Federal Building office tower are the product of weather-data analysis, wind-speed studies, and air-flow modeling, and an integrated design process. Office floors are long and narrow to provide views and promote daylighting. The slender floor plate permits breezes to enter through openings on the tower’s windward elevation and allows venting through the opposite facade. The building’s exposed-concrete slabs are supported by an upturned beam system and have a wave profile in section. The configuration maximizes structural efficiency while increasing surface area, enhancing the slab’s ability to absorb heat generated by people, computers, and lights. The designers protected the tower’s facades from heat gain with a shading scrim on the south-east elevation and frosted-glass fins on the northwest. Some of the openings in the window walls are controlled by the occupants and some by the buiding’s automation system. Awning windows in the northeast and southeast glass curtain walls facilitate cross ventilation of the tower, naturally venting 70 percent of the building.
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final model
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final model
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BUILDING CIRCULATION
ATIENZA, CARDENAS, GALLEGO, LOVE, MENDELSOHN
Awning windows in the northeast and southeast glass curtain walls facilitate cross ventilation of the tower, naturally venting 70 percent of the building.
The designers protected the tower’s facades from heat gain with a shading scrim on the south-east elevation and frosted-glass fins on the northwest. Some of the openings in the window walls are controlled by the occupants and some by the buiding automation system.
The building’s exposed-concrete slabs are supported by an upturned beam system and have a wave profile in section. The configuration maximizes structural efficiency while increasing surface area, enhancing the slab’s ability to absorb heat generated by people, computers, and lights.
The form, structure and orientation of the Federal Building office tower are the product of weather-data analysis, windspeed studies, air-flow modeling, and an integrated design process. Office floors are long and narrow to provide views and promote daylighting. The slender floor plate permits breezes to enter through openings on the tower’s windward elevation and allows venting through the opposite facade.
ANCILLARY SPACES
[MORPHOSIS]
LOBBY FLOOR PLAN
OFFICE FLOOR PLAN
FACILITY TYPE: Office Building LOCATION: San Francisco, CA CLIENT: General Services Administration COMPLETION DATE: Spring 2006 SIZE: 605,000 s.f. (Building), 91,000 s.f. (Site)
SITE PLAN
market street
6th street
7th street
Final Poster
San Francisco Federal Building
mission street