THE GREGORY BATESON BUILDING, 1977-1981

Sacramento, California

Sim Van der Ryn, State Architect

The Gregory Bateson Building was the flagship building of a series of state office projects. These buildings were intended to transform the State of California’s building administration practices. The aim was to move state agen­cies from scattered leased office spaces to more amenable workplaces the state would build to its own higher stan­dards. The Bateson Building was also part of two other programs initiated by then-Governor Jerry Brown to establish new energy performance standards and to revi­talize the state capital office area of Sacramento. It was the first of 13 buildings in what was called the Capitol Plan.

The result is a pleasing contradiction in terms: a pub­licly inviting state office building. It is also remarkably efficient and well tuned to its climate, providing at least 70 percent of its own energy through daylighting, integrated passive design, and intelligent controls. Furthermore, completed construction costs were only $62/ft2, a figure within $0.50/ft2 of conventional office buildings.

TABLE 11.1 Fact Sheet
Project	Building Name Client City Lat/Long/Elev	The Gregory Bateson Building (GBB) State of California, Department of General Services, Governor Jerry Brown Sacramento, California 38.58N 121.50W, 7 m or 22 ft above sea level
Team	Architect Other Team Members Structural Engineer Mechanical Engineer Civil Engineer Electrical Engineer Construction	Sim Van der Ryn, State Architect, and the California Energy-Efficient State Building Program Peter Calthorpe, Bruce Corson, Scott Mathews, Glenn Hezmalhalch, Jim Barnett, Ed Street Karl Stricker Vern Thornburg and Russ Ahrnsbrak Ben Shook Doug Yee and Angleo Spataro Continental Heller Corporation
General	Time Line Floor Area Occupancy Cost Cost in 1995 US$	1977-March 1981. 267,000 ft2 (24,793 m2) gross, not including the enclosed atrium. Government offices, mostly in health care area, about 1200 office workers or 22 occupants per 1000 ft2. $20 million (1978 dollars), $62/ft2. 46.7 million or $175/ft2.
Site	Site Description Parking, Cars	GBB occupies a full 2.5 acre block in downtown Sacramento’s Capitol Area. This district was undergoing revitalization as a mixed-use, low-rise, and urban-village-scale pattern of development. None.
Structure	Stories Plan Foundation Vertical Members Horizontal Spans	Four. Rectangular plan with central atrium. Not determined. Precast concrete ladder frame on concrete piers. Cast-in-place concrete beams with precast concrete double-tee spans and concrete topping.
Envelope	Glass and Glazing Skylights Cladding Roof	Automated window shading with translucent rolling fabric. Skylit atrium of 150 ft (45.7 m) by 144 ft (43.9 m) with 75 ft (22.9 m) height. Laminated wood timber infill and aluminum-framed glass, R-19 cavity insulation. R-19 insulation.
HVAC	Equipment Cooling Type Distribution Duct Type Vertical Chases	Central plant steam and chilled water. Two supplementary 660-ton rock beds are located below the atrium floor and insulated with R-19 expanded polystyrene. Variable air volume. Exposed metal. Flanking the atrium.
Interior	Partitions Finishes Vertical Circulation Furniture Lighting	Glazed to atrium. Acoustical baffles in exposed concrete ceilings. Atrium stairs wrapped around elevator shafts. Open office. Fluorescent and task lighting.

Skylit atrium of 150 feet by 144 feet with 75 foot height.

Two supplementary 660-ton rock beds are located below the atrium floor and insulated with R-19 expanded polystyrene.

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Program

Client

In the early 1970s, the State of California decided that owning its own office buildings would be more practical than its old policy of leasing space. This decision had to recognize that ownership enabled better control of both operating costs and the working environment. Ownership also meant risks, however—risks associated with poorly designed and potentially unmanageable buildings that California taxpayers would be burdened with fixing or abandoning. The problem of realizing the benefits of ownership without assuming unreasonable risk fell to the state architect, Sim Van der Ryn.

Brief

The Capitol Plan was originally drafted in 1960, years before Brown and Van der Ryn stepped in. The idea at that time was to purchase land south of L Street between the capitol and the Sacramento River for development of new high-rise office buildings. Commercial development had moved farther east of the river, and the area around the capitol mall had gradually become a slum. The need for “Old Town” redevelopment and California’s huge postwar appetite for government office space set the plan in motion. Two towers were erected on the west side of the Bateson site, and a central energy plant was constructed. In the early 1960s the California state architect’s office grew in size to be something comparable with the largest architectural firms in the world. When Ronald Reagan became governor, however, cutbacks ensued; building construction programs were halted and office space for state agencies was leased instead. In 1975, when Brown took office, a revised Capitol Plan reported that 1.2 mil­lion ft2 of space was being leased in 55 Sacramento loca­tions. The pendulum had swung too far, and consolidation was in order. This is when incoming governor Brown, only 34 years old at the time, appointed Sim Van der Ryn as state architect to institute the multifaceted new building program.

The new-generation Capitol Plan, presented to the California legislature in 1977, was prepared by representa­tives of broad constituencies. Van der Ryn formed a staff to provide technical assistance. A series of guidelines were then established to transform the compound of day-use office buildings into a 24-hour multiuse campus:

• Clusters of activity centers with cafes and services

• Mixed-use buildings, with residential units included

• Revitalized urban infill to reduce suburban sprawl

• Development of a series of pedestrian and bicycle streets

• Designation of mass transit corridors

• Building height restrictions of 50 ft (15.2 m), or about four stories

• Building entrances that adjoin mass transit stops

• Networking of public and private open space into pedestrian streetscapes

• Reduction of urban “heat island” summer tempera­tures by planting trees

• Provision of mass transit downtown and connection to the suburbs

• Parking lots or garages located on the edge of the capitol area only

• Parking under fringe area freeways with shuttle bus links to the capitol

Site

The capitol district of downtown Sacramento is just east of the Sacramento River. The specific site for the Bateson project, then called “Site 1A,” was a 2.5 acre city block located on Sacramento’s grid coordinates bounded by P to Q, and Eighth to Ninth Streets. It is a short three blocks south of the capitol building and the L Street pedestrian mall that runs from the capitol to the Sacramento River. Immediately east of the Bateson site is a one square block park. On the west side is a paved urban plaza with the two 1960s office towers from the old Capitol Plan occupying opposite corners of that block.

Climate

Figure 11.4 Distribution of July temperatures in Sacramento, California.

Sacramento is 90 miles northeast of San Francisco and 70 miles east of the Sierra Nevada. The city lies between the Sierra Nevada and the softer Coastal Range in the long central California valley that begins at about Red Bluff and then stretches 500 miles south to Bakersfield. Koppen’s classification defines the region as BSk, Cold Mid-Latitude Steppe, placing Sacramento in the same category as San Diego; Roswell, New Mexico; Monterey, Mexico; Jaipur, India; and Cordoba, Argentina. These are dry climates with an annual average temperature below 65°F. Conditions are temperate but sunny and arid. Normal degree-day data reflects the overall mildness: 2679 heating and 1213 cooling degree-days. Because degree-days are taken from daily average temperatures, however, they dis­guise the magnitude of Sacramento’s daily temperature extremes. Characteristically, in dry climates earning Koppen’s “B” designation, intense sun and low humidity introduce large swings between day and night tempera­
tures in the same 24-hour period. July highs in Sacramento, for example, average 93°F and the normal daily low is 58°F, so the average daily temperature of 76°F can be quite misleading.

About 75 percent of the meager 17 in. of annual rain­fall occurs during the five cooler months of November through March. Water supply for the warm dry season comes from snowmelt in the Sierra Nevada that feeds the Sacramento and San Joaquin Rivers before they turn west into San Francisco Bay. The north-south axis river valley also channels winds along its 500 mile course, keeping them predominantly from the south every month but November, when the wind comes from the north. The flanking mountains protect Sacramento from more severe winter storms, but sometimes severe rain or snowfall on the western face of the Sierra Nevada leads to river flood­ings, which have plagued the Sacramento area since 1850.

Patterns of June through October weather are some­times dominated by high-pressure cells that bring a few days of very hot desert air and gusty winds into Sacramento. Other times, a gap in the coastal mountain range at Carquinez Strait occasionally allows cool ocean breezes to travel up the river delta from the San Francisco Bay and bring unseasonably comfortable summer temper­atures to the capital city.

Winter patterns between November and April feature rainstorms from the Pacific. They are usually accompa­nied by mild temperatures but can include gusty winds from the south. Fog occurs during any long absence of the winter rainstorms, when stable air masses tend to lie stag­nant in the valley. These fog events are distinctly uncom­fortable and can blanket the city for days.

Intention

Design Team

The Bateson Building was designed by a team under the direction of State Architect Sim Van der Ryn. One of the lead designers was Peter Calthorpe, who later formed a partnership with Van der Ryn in private practice. Barry Wasserman was deputy state architect and later succeeded Van der Ryn as state architect to complete the building.

Sim Van der Ryn was born in Holland. His family moved to New York City in the early days of World War II, but some of his extended family perished in Nazi concen­tration camps. At an early age, Van der Ryn took refuge in nearby beaches and marshes, a trait common to the child­hood of many environmentalists. Though he grew up wanting to be an artist, his parents persuaded him to earn a degree in architecture at the University of Michigan, Ann

		Jan.	Feb.	Mar.	Apr.	May	June	July	Aug.	Sept.	Oct.	Nov.	Dec.	Year
	Degree-Days Heating	599	401	347	198	74	11	0	0	7	80	345	595	2679
Temperature	Degree-Days Cooling	0	0	0	13	82	206	330	303	212	58	0	0	1213
Extreme High	70	76	88	93	105	115	114	109	108	101	87	72	115
Normal High	53	60	64	71	80	87	93	91	88	78	64	53	74
Normal Average	46	51	54	59	65	71	76	75	72	64	53	46	61
Normal Low	38	41	43	46	50	55	58	58	56	50	43	38	48
	Extreme Low	20	23	26	32	34	41	48	48	43	35	26	18	18
	Dew Point	39	42	43	44	47	50	53	53	51	47	43	39	46
Humidity	Max % RH	91	89	85	78	72	67	69	74	75	81	87	91	80
Min % RH	70	59	52	43	36	31	29	29	31	38	56	70	45
% Days with Rain	42	39	36	24	13	6	2	3	7	15	30	39	21
	Rain Inches	3	2	2	1	0	0	0	0	0	1	2	2	17
Sky	% Overcast Days	58	50	39	27	16	10	3	3	7	19	43	55	27
% Clear Days	22	28	34	39	49	61	78	75	71	56	34	22	48
Wind	Prevailing Direction	SE	SE	SW	SW	SW	SW	SSW	SSW	SSW	NNW	NNW	SE	SW
Speed, Knots	8	8	9	9	10	11	9	9	9	9	8	8	9
Percent Calm	17	15	10	8	6	4	3	5	11	19	23	20	12
	Rain	12	11	11	7	4	2	0	1	2	4	9	11	79
Days Observed	Fog	21	15	8	3	1	0	0	0	1	6	16	22	98
Haze	17	15	8	4	4	2	4	4	9	15	19	17	123
Snow	0	0	0	0	0	0	0	0	0	0	0	0	0
Hail	0	0	0	0	0	0	0	0	0	0	0	0	0
Freezing Rain	0	0	0	0	0	0	0	0	0	0	0	0	0
	Blowing Sand	0	0	0	0	0	0	0	0	0	0	0	0	0

table 11.2 Normal Climate Data for Sacramento

Arbor. While there, he was inspired by a visit from Buckminster Fuller, who opened his eyes “to the power of intelligent design.” After Ann Arbor, Gordon Bunschaft hired him at Skidmore, Owings and Merrill back in New York, but the large office environment had no appeal for young Van der Ryn. He left immediately for California. “Follow your bliss,” he quotes from the popular author and historian Joseph Campbell.

After landing a teaching position at Berkeley he was to hold for 33 years, Van der Ryn began building experimen­tal structures with his students. In 1968 he founded the Farallones Institute with a group of hands-on biologists, engineers, builders, and architects. Its mission was to con­duct research and education in appropriate technology and address concerns about the deteriorating world envi­ronment. When Governor Edmund G. “Jerry” Brown named him to the post of state architect in 1975, Van der Ryn launched the Energy Efficient State Building Program. Later, in 1978, he formed a private practice with Peter Calthorpe, his teammate at the state office. Scott Matthews, another of the Bateson team, went with them.

Farallones became the Ecological Design Institute (EDI) in 1995. EDI continues the multidisciplinary team­work principle. The institute designs buildings, building systems, site and community planning, infrastructure design, and educational programs. The central goal of EDI is to bring beauty and ecology into everyday living.

In his private architectural practice, Van der Ryn has fostered connections with groups of people whose vision was consistent with sustainable design practices. Working with these communities, he has designed a number of “Eco-villages” including the San Francisco Zen Center, the

JAN FEB MAR APR MAY JUN JLY AUG SEP OCT NOV DEC!■ HEATING □ COOLING |

IL

Figure 11.5 Climate analysis graphics.

Lindisfarne Association, and the Ojai Foundation school. The Real Goods Trading Corporation showroom north of San Francisco, the Klein Residence, and an educational program for San Domenico School are among EDI’s latest accomplishments. Sim Van der Ryn is the author or coau­thor of five books, including Sustainable Communities (with Peter Calthorpe) and Ecological Design (with Stuart Cowan).

Peter Calthorpe was born in England and grew up in Coral Gables, Florida. He studied at the Yale Graduate School of Architecture but left the program to pursue his personal interests in ecology and community planning. In 1968, Calthorpe became director of design at the Farallones Institute. Moving on with Van der Ryn, he was a primary designer on the California State Office team for the Bateson Building and in 1978 formed a private prac­tice partnership with Van der Ryn. Calthorpe Associates was established in 1983 to focus primarily on planning issues. His work now includes diverse projects in various – scale settings and many countries. Calthorpe is the author of several books, including the aforementioned Ecological Design (1986, with Sim Van der Ryn) and The Next American Metropolis: Ecology, Community, and the American Dream (1993).

philosophy

Anthropologist and philosopher Gregory Bateson (1904-1980) had become a close friend and influential mentor of Sim Van der Ryn while both were teaching at the University of California at Berkeley. At the 1981 com­memoration of the building in Bateson’s name one year after his death, Van der Ryn spoke at length about the

Sacramento, California Dry-Bulb Temperature, °F Figure 11.6 Bin data distribution for Sacramento. Concentric areas of graph indicate the number of hours per year that weather conditions nor­mally occur in this climate. Similar to elevation readings on topographic maps, highest frequency occurrences of weather are at the center peaks of the graph. (Data sources: Engineering Weather Data, typical meteoro­logical year (TMY) data from the National Climatic Data Center, and the ASHRAE Weather Data Viewer from the American Society of Heating, Refrigerating and Air-Conditioning Engineers.).

important influences of his friend’s work. The thinking behind the Bateson Building deserves a slight detour through some of Gregory Bateson’s contributions.

Gregory Bateson pioneered the field of visual anthro­pology with Margaret Mead. He taught at several institu­tions and eventually became a regent of the University of California. Along the way he became accomplished as a philosopher, naturalist, and writer. His work incorporated cybernetics, systems theory, psychiatry, evolution, genet­ics, communication, and meta-thinking: the science of sci­ence, thinking about thinking, and the nature of nature. His books include Steps to an Ecology of Mind (1971) and Mind and Nature (1979).

Bateson was concerned with systems as patterns and with meta-patterns, the patterns that connect other pat­terns. He saw a need to shift from outdated old world views, from first-order knowledge about things to a new understanding about the interconnectedness of all things, from parts to the whole, from structure to process, from entities to networks, and from rigid truths to inclusive approximation. Above all, Gregory Bateson wished to illu­minate the idea that everything is whole and that human­ity is the “pattern that connects.”

Intent

Sim Van der Ryn interpreted one of Bateson’s last person­al comments to him as inspirational to the design of the state office building. The comment had to do with “sensi­tivity to differences.” To Van der Ryn, these differences are what produce flow, and in architecture this flow is about the connectedness between buildings and people in a nat­ural environment. The Bateson Building would be a con­tainer of flows and a network of connections.

Beyond the philosophical directive, this stated inten­tion gave the design team some tangible goals. All of them are statements about systems integration, mirroring Bateson’s assertions about connected systems in a literal but equally idealistic way. Public space, for example, would be the building focus and would connect it to the public network of the campus. Flows of energy, light, and sound were given clarity, and their management was to be tuned to occupant comfort, health, and productivity. Interconnectedness became a theme for both connecting systems of the building together and for meshing the building into a coherent Sacramento capitol campus.

Critical Technical Issues

Inherent

Office workplaces are discussed as a typology in the intro­duction to Chapter 6. The Bateson Building’s specific requirements reflect the practicalities of a state-owned facility. Flexibility was especially important to the Department of General Services because the users of the building were likely to change several times and require adaptation to their specific agency’s incoming workforce. Most changes of occupancy occur only with a new owner, but not so here with state ownership.

Other concerns mention the preference for stairs and tie this to the four-story limit on building height. On-site parking was prohibited. A ratio of 20 percent fixed parti­tion space to 80 percent flexible open office plan was sug­gested. Enclosure and security, clarity of circulation, and other typical requirements generated the criteria.

Finally, the state wanted a building that addressed long-term costs. An estimate placed the building cost over its life cycle at only 8 percent of the total expense. Personnel salaries were pegged at more than 90 percent. The state wanted this equation optimized by provision of worker-friendly offices with amenities like natural light and view, individual environmental controls, and acousti­cal planning for privacy and quiet. This level of occupant

comfort also meant that energy systems would somehow have to be both satisfyingly generous and efficiently stingy.

Contextual

California’s Title 24 state energy standards were established for the Office Building Program after 1975. These set an energy reduction goal of 50 percent (down to 19,900 Btu/ft2 yr or 6042-W/m2 yr) for state office buildings. These guidelines were included in the 1977 program docu­ment, “A Competition for the Design of an Energy Efficient Office Building,” as a separate document entitled “Building Value: Energy Design Guidelines for State Buildings,” dated January 12, 1976. Interestingly, both documents included forewords signed by Sim Van der Ryn while he was still state architect. Stage I entries for the competition were due May 27,1977, and Stage II entries were due in July 1977. In fact, Van der Ryn was listed as a member of the competi­tion jury along with Director of General Services Leonard Grimes, California Energy Commissioner Alan Pasternak, architect William Caudill of CRS, and no less than Fred Dubin of Dubin-Bloome engineers, who was Louis Kahn’s mechanical consultant for so many years.

The 105-page competition booklet included major sections on the competition rules (18 pages), existing con­ditions (16 pages), climate (interestingly, the largest sec­tion, at 22 pages), the Capitol Area (6 pages), and the energy program (10 pages). It specified not only the for­mat of entry drawings, but also the inclusion of cost esti­mates and energy conservation schemes. The Building Value reference supplement, in contrast, dealt more with state-of-the-art energy conservation design methods, the cost value of worker productivity, life cycle cost analysis, and categories of energy use in buildings.

Intentional

Van der Ryn’s commitment to interconnected flow and sensitivity to differences established metaphysical goals for how the building would connect with nature and the laws of physics. The program guidelines set up a decidedly more humanistic and experiential approach to networks by weaving the office-building program into a pedestrian format for the capitol campus.

Appropriate Systems

Precedent

Deep-plan atrium buildings evolved from the first attempts to crowd large buildings together in dense urban settings where meandering plans and extended forms were impractical. Before the advent of mechanical services, the atrium was needed to provide light and air to interior rooms of a building. Later, the atrium became a social focus in highly serviced buildings. Hotels frequently use atruims to unite vertical circulation and servicing with aesthetic grandeur. The energy crisis of the early 1970s brought back the atrium as a thermal buffer space and daylighting strategy.

Site

“Site” at the Bateson Building happens at the campus or village scale. The building itself reaches curb to curb, except for important entry courts on the east and west sides. At the street periphery, trees and landscape ele­ments are used to soften the face of the giant block and blend in with the capitol campus scheme. Inside, offices form a rectangular donut, 80 ft (24.4 m) thick around the central court. At the core is the skylit atrium, serving as public space, lunchroom, employee lounge, and passage­way connecting a city park on the east to an urban plaza on the west.

Capturing the residual area of the site within the donut enclosure of program space is the raison d’etre of the Bateson Building. This strategy secures a comfortable space for people to gather and move through, provides a high level of passive climate control, and contains some of the mechanical system components. Most significant per­haps, the giant atrium acts as an outdoor room, weaving the Bateson Building into the village scale plan for the capitol area’s redevelopment.

Two entryways are staggered pinwheel fashion toward the southwest and northeast corners of the atrium. Outside, small courtyards on those corners of the site meet the crosswalks and lead into the walk-up lobbies through skeletal extensions of the building’s open concrete frame. Up and down the building are several terraces, including a large dining deck at the second level that dominates the northeast entry court below.

Structure

The desire for a massive concrete structure grew from the intention of capturing cold night air in Sacramento’s desertlike climate and harvesting it as cooling energy dur­ing occupied hours. Resisting the notion of mass was the need for daylight to flow into and through the building. Resolution was achieved by restricting the vertical struc­ture to an open frame and using double-tee concrete beam floor spans.

The building rests on concrete piers designed for soft soil. The poor load-bearing quality of soil on the site is related to the town’s history of flooding. After a devastat­ing flood in 1862, thousands of cubic yards of soil were brought into “Old Town” Sacramento in an effort to raise grade elevations by 12 ft (3.7 m) and avoid future wash­outs. This soil was mostly dredged from the river and is formed from decomposed river rock and granites. It gen­erally consists of silt, sand, and expansive clays.

Precast concrete columns are set on the piers, and beams are poured in place to produce fixed connections. The floors are double-tee concrete beams with a finish concrete topping. The structure is left exposed to both the interior and the exterior.

The geometry of the structure is set by the establish­ment of a grid of “ladders,” acting as a three-dimensional portal frame, about 14 ft (4.3 m) wide. This ladder frame provides lateral bracing and rigidity. Eight sets of these ladders run from east to west through the structure. They start at the outside walls, divide the office space, and bor­der the atrium. Between the ladder frames are seven bays of approximately 35.5 ft (10.8 m) spanned by the concrete tees. Across the structure from east to west, the building is divided into 12 spans of about 24.25 ft (7.4 m).

Envelope

Daylighting and shading were the keys to envelope design. Insulated glass in aluminum framing covers all four facades from the bottom of the concrete tee structure to a short laminated-wood knee wall. To avoid intense direct solar gain in the dry climate and still maximize indirect daylighting, operable exterior canvas shades are used on the east and west elevations. These bright orange translu­cent shades are motorized and held in place with steel cables fixed at their bases. A computer-based automation system controls their positions. Interior metal blinds on all four orientations allow for occupant control and act as small-scale light shelves to reflect light off the white paint­ed concrete ceilings and move it deeper into the interior areas. The south elevation is protected by having the glass pulled back one bay inside the ladder frames and covering the outside frames with a trellis of concrete beams. North elevation glass is left unshaded and faces a taller building. In addition, all four borders of the site are planted with trees to provide pedestrian shade and some solar protec­tion for the building envelope.

Exterior wall areas behind the 3 ft (914 mm) high lam­inated-wood spandrels are framed in steel studs and filled with R-19 insulation. The roof is also insulated to R-19.

Numerous setbacks and terraces are carved into the city-block-sized structural grid. This allows for pedestrian – friendly entries on the northeast and southwest corners. It also softens the form of the building and adds human-scale spaces for both occupants and downtown pedestrians.

The roof of the atrium is clustered with numerous components. First, there are the grand south-facing sky­lights, equipped with operating vertical louvers that can track toward the sun in winter and shade away from it in summer. Next are the north-sloped skylights to provide smaller apertures and cooler light. These are most effective in the clear-sky Sacramento summers, when light is more abundant and smaller daylight apertures will capture plenty of light without introducing direct solar gain. Completing the sawtoothed arrangement of the atrium roof are 2000 ft2 (185 m2) of active solar water heating col­lectors. All of these components are pushed to the visibly hidden center of the roof area and do nothing to increase the apparent height of the building above the four-story offices. Around the edges of the skylights are airshafts and fans for ventilation.

Mechanical

In organizing the comfort systems in this building, priori­ty is appropriately given to passive systems. Mechanical HVAC systems are, however, integrated with the overall energy scheme by using mechanical ventilation modes to strategically capture, store, and distribute passive heating and cooling. The environment provides most of the ener­gy needed; the mechanical systems are set up to channel the energy flows.

Figure 11.8 Monthly performance estimates for the Bateson Building. (Adapted from Stein and Reynolds, Mechanical and Electrical Equipment for Buildings, 8th ed.)

Cooling of the building relies primarily on night venti­lation. This passive strategy provides about 90 percent of the annual cooling required. Figure 11.9 shows tempera­tures for the coolest and warmest hours of an average July day in Sacramento and corresponding July data for Houston, Texas. In Sacramento the arid climate reradiates accumulated daytime heat very quickly to the clear night sky. Consequently, there are 250 hours per month of night­time temperature below 65°F versus 494 hours per month of daytime temperatures over 65°F. If temperature is accounted for, as well as hours of occurrence, there are 1235 degree-hours below 65°F and 7754 degree-hours above 65°F. This degree-hour data predicts heating and cooling requirements from temperature loads just as degree-days data does, but at a finer level of detail that does not disguise daily temperature fluctuations. Degree-hour data is used predominantly in calculating cooling loads. Notice that in humid climates like Houston, where there are no July hours below 65°F, nighttime ventilation cooling is ineffective.

By using the mechanical system to flush the building interior with cooler night air for those 250 Sacramento hours below 65°F, enough heat can be absorbed by the exposed concrete floors and ceilings to carry the building through the following day. This can be visualized as a bat­tery that is charged with heat by day and discharged by cooling it at night. One cubic foot of concrete will store about 30 Btu of sensible heat for every degree it is cooled or warmed relative to room temperature. The exposed double-tee ceiling and concrete deck floors at the Bateson Building continually exchange this energy with the indoor air and its occupants. Two 660-ton rock beds in insulated basements below the atrium floor serve as additional remote thermal storage that can be either charged or har­vested by circulating air directly through them. If the rock beds alone were charged to 10°F below room temperature, they would store about 400 ton-hours of cooling capacity. Figure 11.8 shows that nighttime ventilation, along with the rock bed storage system and some daytime ventilation on cool days, provides an estimated 95 percent of the annual cooling needs.

Direct-gain passive heating is a much less important concern because of the unavoidable high levels of heat produced inside the compact building by people, lights, and equipment. These internal gains offset most tempera­ture-driven heat loss from the offices through the envelope and by ventilation, even in the coldest months. Mechanical heat in the occupied offices is required only for cold morning start-up. The nonconditioned atrium is another matter, however. As a transitional space, its primary source of heat is solar gain through the three rows of south-fac­ing clerestory skylights. Warm air is kept at floor level by several canvas tubes with fans at the bottom to pull strati-

Figure 11.10 View of the atrium.

fied heat down from the atrium ceiling. Exposed mass in the atrium floor helps stabilize temperatures, and from November to February the rock beds can be utilized to store heat for long periods of time.

Steam and chilled water for backup mechanical serv­icing come from a capitol district energy plant nearby. Variable-air-volume distribution fans are used for cooling in tandem with hydronic reheat coils at each zone for heat­ing. Outside air for ventilation can be moistened and pre­cooled by evaporative spray air washers. Domestic hot water is provided primarily by 2000 ft2 (185 m2) of solar collectors on the atrium roof. Finally, operation of the entire building is coordinated by a computerized automa­tion system.

Interior

Interior space is organized around the structural frame as a series of four rings. At the outermost edge are rooms with exposure to daylight. These are entered through the second ring, a double-loaded circulation corridor defined by the structural ladder frame. An interior ring of office space comes next, with daylight exposure to the atrium skylights. Circulation makes up the innermost fourth ring, aligning a continuous walkway balcony with elevators hid­den behind suggestively prominent stairways. Finally, there is the central atrium court.

The basic scheme is interrupted at the ground floor by generous entries on the east and west. Wide lobbies con­nect the atrium to exterior canopy extensions of the con­crete building frame. These two-story open frames clearly identify the passageway into and through the building. Inside the atrium, finishes match the exterior landscaping. Brick tile floors and wood benches are set with bright orange destratification tubes and deep blue mechanical shafts. Balcony railings are made of 3 ft (914 mm) high solid laminated-wood panels identical to the exterior wall infill spandrels.

Finishes in the office space include acoustical baffles suspended in the precast double-tee ceilings. Most of the partitions between offices and the atrium are glazed to admit illumination from the skylights.

Integration Highlights

Physical

• The atrium serves both as a common space and for protected but unconditioned circulation.

• The double-loaded corridor is also a mechanical serv­ice spine for the conditioned spaces.

Visual

• The atrium is treated as an outdoor space to visually establish it as a public link between the park and the urban plaza.

• Landscape elements and tree plantings are shared with surrounding blocks to create a pedestrian cam­pus atmosphere.

• Repetition of natural materials and bright colors lends an informal atmosphere to outdoor and atrium spaces.

Performance

• Exposing the concrete tee structure provides internal thermal mass and allows for 10.5 ft (3.2 m) ceilings without increasing the height of the building.

• Open-frame concrete column and beam elements allow free flow of daylight.

• The total integration of mechanical and passive sys­tems provides, harvests, and controls natural energy flows.

• The active shading systems and personal control of window blinds integrates the benefits of light, shade, privacy, and view without sacrificing performance.

Discussion

The Bateson Building was among the first of a generation of structures designed in response to the 1970s energy cri­sis. Like so many similar buildings that explored new com­binations of technology, it has had its problems. A year or so after occupancy, complaints about the indoor air qual­ity and claims of sickness caused by working in the build­ing led to an in-depth investigation. About 80 percent of the variable-air-volume control boxes proved to be mal­functioning. Consequently, insufficient air was being delivered to the occupants and indoor pollutant concen­trations could have affected their health. The problem was apparently made worse by a rushed completion schedule that moved people in before some of the volatile chemicals in the new materials and installation work had time to air out. Formaldehyde, for example, a principal irritant found in many fabrics and plastics, was reportedly introduced at the last minute by an indiscrimate choice of office parti­tion systems.

The integrated passive schemes could not be blamed for these problems. In fact, as long as the building was in the night-ventilation summer mode, indoor air quality problems did not become critical. When the building was sealed up for its first season of cool weather, however, the reduced outdoor air quantity became all too apparent. The problems encountered were attributable to the con­ventional mechanical system and the rushed final comple­tion for occupancy.

The first generation of Green architecture began with ideas about energy conservation, passive systems, and eco­nomic benefits. The Bateson Building is one of the prede­cessors of the second Green generation, a bridge from the first experiments. Founded on the ideals stimulated by Gregory Bateson himself, as well as the principles and goals of its chief designers, the building is a prominent example of systems thinking, of interconnectedness, of mindful intentions, and thus of integration in the greenest sense.