David & Lucile Packard Foundation Headquarters: Los Altos, ca
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1 8 INSPIRATION GRACEFUL While some buildings wear their net zero design on their sleeves, the Packard Foundation Headquarters employs energy-efficient and sustainable technologies in a more understated fashion. Slanted roof lines, extensive exposed wood and transparent spaces create a warm, classic Californian feel to the space. The net positive energy building has achieved the Packard Foundation’s goal of creating a building that is attractive, innova- tive, healthy and comfortable. The project received ASHRAE ’s Award of Engineering Excellence in 2014. It is only the fourth project to receive it since the award’s creation in 1989. PETER RUMSEY, P.E., FELLOW ASHRAE; ERIC SOLADAY, P.E., ASSOCIATE MEMBER ASHRAE; AND ASHLEY MURPHREE C A S E S T U D Y © Jeremy Bitterman Winner of ASHRAE Award of Engineering Excellence, 2014.
This article was published in High Performing Buildings, Winter 2015. Copyright 2015 ASHRAE. Posted at www.hpbmagazine.org. This article may not be copied and/or distributed electronically or in paper form without permission of ASHRAE. For more information about High Performing Buildings, visit www.hpbmagazine.org. W i n t e r 2 0 1 5 H I G H P E R F O R M I N G B U I L D I N G S 1 9 1 9
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man comfort satisfaction ranks in the 96th percentile. The building tells the story that it is possible to reach energy neutrality without sacrificing comfort. In fact, the design strategies such as opera- ble windows and blinds, individually dimmable lighting and a dedicated thermostat per chilled beam in each office have actually enhanced com- fort by giving more control to users. Integrated Design Exercising the process of integrated design, the team of architects, land- scape architects, engineers, design- ers, and contractors worked together to complete a climate and weather analysis and a daylight and sun- path analysis; established proper architectural massing; detailed an advanced envelope design; and initi- ated an exhaustive study to predict and minimize plug loads — all before the team made any major decisions about the building’s design. The analysis-driven design meth- ods led to a desirable solar orien- tation, external shading, a 50% increase in framing member spac- ing, deeper wall cavities, higher insulation values and continuous T he success of the design can be measured on several fronts. The in- operation energy use intensity of 23.5 kBtu/ft 2 · year has been decreasing as enhanced com- missioning continues. The building confirmed its net-positive energy status in July 2013, generating 418 MWh of electricity in the first year of operation with on-site 303 kW photovoltaic rooftop panels. It con- sumed only 351 MWh of electricity and zero natural gas. (See more at “Tracking the Path to Net Zero Energy,” tinyurl.com/bnx9meg.) Occupants have responded to comfort surveys reporting superior comfort, acoustics, healthy indoor air, abundant natural light and an overall pleasant environment. Post-occupancy feedback shows 97% of occupants are satisfied with the building overall, and thermal B U I L D I N G A T A G L A N C E Name David & Lucile Packard Foundation Headquarters Location
Los Altos, Calif. (12 miles NW of San Jose) Owner David & Lucile Packard Foundation Principal Use Office
Employees/Occupants 120
Expected (Design) Occupancy 120
Percent Occupied 85–90%
Gross Square Footage 49,000 Conditioned Space 49,000
Distinctions/Awards ASHRAE Technology Award of Engineering Excellence and First Place, New Commercial Buildings, 2014; LEED NC 2009 Platinum, 2013; International Living Future Institute Living Building Challenge, Net Zero Energy Building certification, 2013; American Institute of Architects, COTE Top Ten Award, 2013; University of California Berkeley Center for the Built Environment, Livable Buildings Award, 2014 Total Cost $37.2 million
Cost per Square Foot $756
Cost of “Replicable Warm Shell” Envelope $23.5 million at $477/ft 2
design that allows for net zero) Occupancy July 2012 Opposite The view from the street wel- comes visitors with a biophilic roof garden and landscape, which doubles as a storm water bioswale. Hiding below the grand entry are four storage tanks for rainwater capture and chilled water thermal storage. Below The north-facing hallway overlooks the collaborative courtyard and connects the sleek wooden interiors with the out- doors. Daylight floods the space while exterior shades block excess heat before it enters the building. D A V I D & L U C I L E P A C K A R D F O U N D A T I O N H E A D Q U A R T E R S Production Use
Aug 2013 46,559
28,403 Sep 2013
37,341 25,261
Oct 2013 29,985
27,084 Nov 2013
19,203 31,470
Dec 2013 18,592
41,312 Jan 2014
18,462 35,575
Feb 2014 19,370
29,110 Mar 2014
29,457 22,033
Apr 2014 42,466
25,861 May 2014
50,963 21,648
Jun 2014 54,718
24,559 Jul 2014
52,072 26,892
Total 419,188 339,209 F I G U R E 1 M O N T H LY E L E C T R I C I T Y P R O D U C T I O N , U S E ( K W H )
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2 0 insulation for increased overall thermal performance, a well-insu- lated floor slab and roof, and R-6 triple glazed windows with ther- mally broken fiberglass frames and argon fill. The envelope upgrades allowed the mechanical engineers to get rid of perimeter heating systems. The enhanced envelope also cre- ated excellent stability, control and symmetry of indoor temperatures. The courtyard and narrow floor plan design allows full capability of natural The design team generated a base design “replicable warm shell” that can be functional and energy neu- tral in many climates, while leaving the aesthetics up to the designer. The Packard Foundation web site, shares information to proliferate the positive impact of the headquarters’ green design (see “Sustainability in Practice” at tinyurl.com/ntu2rwn). Lighting and Daylighting The building is designed to be fully daylit. The daylight design put a pri- ority on avoiding excessive brightness in daylit areas. Because the build- ing is oriented 58 degrees off a true east-west axis, external fixed shad- ing devices are supplemented with ventilation and optimized daylight. The weather and sun-path analysis optimized the custom design of solar controls and motorized shades for avoidance of unwanted solar heat gain. The analysis also informed the arrangement of the floor plan. These up-front, analysis-driven decisions are imperative to the overall success of the mechanical design, and the design team considers them part of the mechanical design. The Packard Foundation, in keep- ing with its philanthropic mission to drive a sustainable future, encour- ages replication of its headquarters. Annual Water Use Storage tank level transmitters have just been correctly installed and calibrated to collect this data. Baseline data will be gathered from July 2014 to July 2015. W A T E R A T A G L A N C E E N E R G Y A T A G L A N C E Annual Energy Use Intensity (EUI) (Site)
23.5 kBtu/ft 2
Electricity (From Grid) 14.2 kBtu/ft 2
Renewable Energy 9.3 kBtu/ft 2 Annual Source (Primary) Energy 54 kBtu/ft 2 Annual On-Site Renewable Energy Exported 19.8 kBtu/ft 2 Annual Net Energy Use Intensity – 5.6 kBtu/ft 2 Savings vs. Standard 90.1-2007 Design Building 46%; 76% reduction from national median EUI for building type Heating Degree Days (Base 65˚F) 2,832 (historical mean for Palo Alto, Calif.) Cooling Degree Days (Base 65˚F) 302
(historical mean for Palo Alto, Calif.) Hours per Week Occupied 55 S U S T A I N A B I L I T Y A T T H E C O R E Sustainability was considered in a holistic way from the start of the new Packard Foundation Headquarters. Carbon analysis was performed on all sources, including employee commutes and business travel. Reducing and eliminating building mate- rials was always the first priority. One outcome of this perspective was the elimi- nation of the $8 million parking garage and the associated concrete in favor of a Transportation Demand Management pro- gram that includes a shuttle to and from a train and bus transit hub one mile away. Deep analysis of the building wall system yielded a wood framing system with 24 in. on center studs. This cut framing by close to 30% compared with traditional framing at 16 in. spacing, and allowed for better insulation of the walls. Beauty and biophilia, the psychological well-being provided by connection with nature, went hand in hand in the design of the building and the surrounding environ- ment. Biophilia is evoked throughout the interiors with natural materials echoing the rolling grass hills of the local environs. Interior accents include river rock beds, oak tree images, wood finishes and con- nection to the landscaping surrounding the building, which relies on 90% native plants. The ecosystems of the landscaping echo grasslands and woodlands. The outdoor courtyard between the two wings of the building acts as a second room of the project. It is designed to be warm in the winter and cool in the summer through plantings and building proportions. Overhead active chilled beams bring comfort and ventilation to one of many collaboration spaces without sacrificing architectural delight. © Jerem y Bitter
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exterior automated shading blinds. Internal dimmable ambient light- ing is coupled with LED
task light- ing. Extensive daylight modeling of the spaces during design helped optimize window and shading device placement. Water
California’s prolonged and worsening drought highlights the need for lead- ership in sustainable water practices and underscores the value of broadly applicable water efficiency strate- gies. The site landscaping comprises various native, drought-resistant plantings watered via a digitally con- trolled drip irrigation system. All of the rainwater falling on the building roof is captured and stored in two 10,000 gallon storage tanks, one each dedicated to meeting 60% of irrigation and 90% of toilet flush- ing. Potable water use for sewage conveyance is further reduced with the installation of waterless urinals and low-flush toilets. Low-flow fixtures are used through- out the building at lavatories, sinks and showers. These measures result in a 69% reduction in potable water use compared to the LEED
baseline • Uses water as the energy delivery medium; • Moves only the minimum amount of air necessary; • Avoids reheat; • Minimizes static pressure drop in distribution; and • Leverages climate and diurnal temperature swings. To align with these strategies, the engineering team chose two-pipe active chilled beams as the distri- bution system. Active chilled beams operate by for a typical building. Ninety percent of the rainwater runoff from the max- imum storm is managed on site. HVAC
Building mechanical systems serv- ing the indoor environmental qual- ity of the space are at the forefront of the building’s innovation. The mechanical design has led to sev- eral awards, including a 2014 First Place Technology Award and the Award of Engineering Excellence from ASHRAE. Above
The project team looked beyond the energy demands of daily building opera- tions and tackled transportation energy. Incorporating advanced telecommunication spaces impacts air travel tremendously. Right
The variety of operable glazing ele- ments offer user-controlled thermal com- fort. The upgrade to R-8 insulating glazing resulted in a first cost savings by eliminating perimeter heating. © Jerem y Bitter
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2 2 of three parts room air to one part sup- plied air. A room with increasing cool- ing needs does not require increasing airflows because variable water flow to the coil within the chilled beam will address variable cooling needs. At the Headquarters, the venti- lation-only air supply needs sig- nificantly reduced the airside system capacity in comparison to a traditional variable volume with reheat system. The DOAS
ramps up and down based on a target CO 2
The system has performed well, allowing operating airflows to be less than designed, while still providing comfort by exceeding ANSI/ASHRAE 62.1-2007, Ventilation for Acceptable
The ventilation air is delivered to the chilled beams at 68°F during the cooling season, compared with the 55°F air typical of variable air volume reheat systems. This system eliminates energy wasted by reheat- ing overcooled air. The building does not require perim- eter heat. The envelope is enhanced to displace the cost of distributing hot delivering tempered ventilation air to each space, and adjust the tempera- ture of the space by inducing room air with the ventilation air across water coils within the active chilled beam diffuser. They operate elegantly and efficiently with very few moving parts. Distribution:
Active Chilled Beams. Water carries over 3,000 times the amount of energy per volume compared with air. So, a hydronic distribution system is a much more effective means of delivering heat to and from the occupied spaces than forced air (Figure 2). The team chose a dedicated outdoor air ventilation system ( DOAS
) that is decoupled from the heating and cool- ing needs of the space to avoid unnec- essary air delivery. The capabilities of active chilled beams allow the space to be heated or cooled with nothing more than minimum ventilation air by inducing air from the room at a ratio The courtyard at the center of the building plays a key role in the full daylighting and natural ventilation strategies by keeping floor plates within acceptable distance from operable glazing. D AV I D A N D L U C I L E PA C K A R D : L I F E T I M E P H I L A N T H R O P I S T S David and Lucile Packard were philan- thropists long before they helped trans- form a small electronics shop in their garage into one of the world’s leading technology companies. David met Lucile on the Stanford University campus, where Lucile served as a volunteer at the Stanford Convalescent Home, which treated children with tuberculosis. Later, the two made philanthropy a family concern by discussing with their children which local organizations they should support. Caring about others and the community around them was a core value. David believed that “management has a responsibility to its employees, to its customers, and to the community at large.” Under his leadership, Hewlett- Packard pioneered many innovative ben- efits and management concepts, such as flexible working hours, catastrophic medical coverage, and open offices. David and Lucile formalized their pas- sion for philanthropy in 1964 when they established the David and Lucile Packard Foundation. For more than 50 years, the David and Lucile Packard Foundation has worked with partners around the world to improve the lives of children, families, and communities — and to restore and protect the planet. Source: www.packard.org © Jeremy Bitterman HPB.hotims.com/54437-4 H I G H P E R F O R M I N G B U I L D I N G S W i n t e r 2 0 1 5 2 4
2 4 Building Owner/Representative David & Lucile Packard Foundation Architect EHDD Architects General Contractor
DPR Construction MEP Engineer Integral Group (Engineer of Record Peter Rumsey) Structural Engineer Tipping Mar Civil Engineer
Sherwood Design Engineers Landscape Architect
Joni L. Janecki Associates Daylight Design
Loisos and Ubbelode Commissioning Agent Altura
Net Zero Systems Engineer
Travis McDaniel, Point Energy Innovations Building Engineer Juan Uribe, The David and Lucile Packard Foundation Headquarters B U I L D I N G T E A M water to the chilled beams. Building with the highly insulated walls and triple element glazing only requires morning warm-up, which is accom- plished through the use of the DOAS
air delivered at 76°F to 78°F. Piping and Ductwork. Next,
the engineering team stressed the importance of thoughtful in pressure drop has a compounded impact on energy savings. The team used larger duct and pipe sizes throughout, and used 45 degree fit- tings in place of 90 degree elbows wherever possible to reduce friction and energy use. Central Plants and Thermal Storage. The active chilled beam distribution system is comple- mented by central heating and mechanical layout to reduce energy wasted in the distribution of air and water. Friction in ducts and pipes causes pressure drop in the fluid, which drives the sizing and energy use of fans and pumps. The corresponding horsepower required to push fluid through the system varies by the square of the pressure drop. So a small reduction Water Conservation Native drought resistant plants watered via digitally controlled drip irrigation. Two 10,000 gallon storage tanks for rainwater capture to meet 60% of irrigation and 90% of toilet flushing. Overall 69% reduction in potable water use through above measures combined with efficient fixtures, urinals and toilets. Ninety percent of rainwater from the maximum storm will be managed on site through collection and porous landscaping. Recycled Materials At least 20% of content recycled. Daylighting Investigated with an extensive daylight model allowing all spaces to be fully daylit. External fixed shading supplemented with exterior automated shading blinds to avoid excessive brightness. Carbon Reduction Strategies Carbon analysis performed. Emissions reduced through use of a wood/steel hybrid structure and wood-framed walls while the concrete mix featured 70% cement replace- ment using slag. The total embodied CO 2 of 1,790 tons pays off in 4.4 years when com- pared to the former Packard Foundation Headquarters yearly operational CO 2 of 409 tons, justifying the construction of a new net zero energy building. Elimination of underground parking structure (reduced embodied emissions by 25% alone). Transportation Mitigation Strategies Elimination of $8 million parking garage with a Transportation Demand Management program that included a “last mile” shuttle to and from a train and bus transit hub. Other Major Sustainable Features • Two-pipe active chilled beams heating and cooling distribution with decoupled dedi- cated outside air ventilation system. Saves energy by reducing air handling equipment and reheating over-cooled air in a tradi- tional variable air volume system. • Perimeter heating eliminated through enhanced envelope. • Larger duct and pipe sizes throughout with 45 degree fittings wherever possible. K E Y S U S T A I N A B L E F E A T U R E S Above
The 303 kW PV installation gener- ated 19% more energy than what the build- ing used during its first year of operation. Left
Layered shading strategies are dis- guised as architectural features with custom overhangs and occupiable balcony space. © Jeremy Bitterman © Jerem
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operation, and thermal storage sys- tems retain the process water until it is needed. The chilled water is produced, without the use of a compressor, by a two-cell, 480 ton cooling tower. The cooling tower operates at night cooling plants that take advantage of the Los Altos climate and diurnal temperature swings, and by the high performance building envelope. At the Headquarters, the central sys- tems generate chilled water and hot water when outside air temperatures are most efficient for the equipment with waterside economizing using the cool night air for “free cooling.” The water from the cooling tower is coupled with a plate and frame heat exchanger and a 50,000 gallon storage tank of 58°F chilled water (compared with 40°F to 45°F water typical of variable air volume reheat systems). When the outside air dew point is above 58°F, heat pumps in the
DOAS units dehumidify the F I G U R E 2 I N D U C T I O N D I F F U S E R C O O L I N G Ventilation Air Coils Induced Air Induction Diffuser (Chilled Beam) • Lower amount of outside air used to meet ventilation requirements • Smaller air handler and ducts • Lower energy use due to lower volume of outside air to cool • Lower reheat requirement uses less energy Ventilation + Induced Air (1:3 Ratio) Roof Type
Wood framing, R-32.5 rigid board insulation, standing seam metal roof Overall R-value R-35.7
Solar Reflectance Index 41
Walls Type
2 in. × 6 in. wood frame, 24 in. on center with R-19 insulation between framing and R-4.2 continuous rigid min- eral wool insulation with furring strips Overall R-value R-18.2
Glazing Percentage 46.3% window-to- wall ratio Basement/Foundation Slab Edge Insulation R-value 2 in.
expanded polystyrene (EPS) foam, R-8 Basement Wall Insulation R-value
3 in. EPS foam, R-12 Under-Slab Insulation R-value R-8
Windows Effective U-factor for Assembly U-0.17 Solar Heat Gain Coefficient (SHGC) 0.25 Visual Transmittance 0.57 Location
Latitude 37.38°
Orientation 328°
B U I L D I N G E N V E L O P E Large diameter custom piping crosses the mechanical room at varying angles, a result of using 45 degree fittings in place of 90 degree elbows when possible. The reduction in friction, from the larger diam- eter and 45 degree fittings, results in an exponential reduction in pump energy. Spaces are designed to provide psycho- logical well-being through connection with nature. Highlighting this connection, the outdoor courtyard is intimately tied to the building as if it is another room. © Jeremy Bitterman © Jerem
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2 6 ventilation air to avoid condensation at the chilled beams. The heating hot water is produced by an air-source heat pump with 865 MBH
of capacity having three to four times the performance of stan- dard electric water heaters. Up to 567 gallons of hot water at 105°F is produced and stored, compared with 140°F to 180°F used for reheat in typical variable air volume systems. During the heating season, warm air heats the building during a morning warm-up cycle, and the envelope and internal loads are enough to maintain comfortable temperatures for the remainder of the day. Conclusion The success of a building can be judged by the reaction of its occu- pants. In the case of the Packard Foundation, the occupants value their comfort as well as protecting the environment. On both accounts, the building has been successful. Nonetheless, the impact and importance of the project is not confined to the occupants. The true impact will be based on how this building influences the design com- munity in the years to come. • A B O U T T H E A U T H O R S Peter Rumsey, P.E., Fellow ASHRAE, is founder and CEO of Point Energy Innovations in Oakland, Calif. Eric Soladay, P.E., Associate Member ASHRAE, is managing principal of the Integral Group in Oakland, Calif. Ashley Murphree, LEED AP, is a mechanical engineer at Integral Group in Oakland, Calif. L E S S O N S L E A R N E D The Packard Foundation building is a treasure trove of lessons learned. The design and construction team is actively sharing the lessons with the larger building community. Innovative Buildings Depend on Controls That Work. Several initial problems were encountered, including condensation on the chilled beams when controls were not working correctly. The condensation caused by the control system mistakenly being set at 45°F instead of the 55°F to 60°F design setpoint and many other con- trols issues were identified and rectified during commissioning. Commissioning is key in all buildings, but is especially so in advanced and more innovative buildings. Further Reduction of Energy Use. Over the first two years of operation the building engi- neer played a key role in reducing energy use by an additional 5% to 10% through tuning and more actively understanding the dynamics of the building. Some of the opportunities he found included optimal times to turn HVAC equipment on and off, additional ways to get users to take advan- tage of the operable windows and further plug load reduction opportunities. This made it possible to go beyond net zero energy to a net positive outcome where the building gen- erates more energy than it uses. Although energy use has been reduced, the occupant comfort level has actually improved. Comfort has always been and will continue to be the Foundation’s number one goal. Getting Plug Loads Under Control Was Key in Lowering the Size of the PV System. The cost of the PV system was reduced by $170,000 through the use of lower energy office equipment and simple time clock and/or occupancy control of the equipment. Reducing Risk of New Applications. During
a cold snap in the first winter of operation, two of the four air-source heat pumps failed due to manufacturing defects. Using this type of heat pump for this type of building was a new application. It is important to design out some of this risk through such things as redundancy, and work with owners to make sure they understand the risks of nonconventional systems. Computer Notification of Conditions for Natural Ventilation. The manually operated natural ventilation system worked best when users were given clues about when to use it right at their desk instead of near the coffee area. A simple software fix was set up that gave users notification at their computer. Cost Benefit of Chilled Beams. Although the chilled beam system including water- side economizers came at a 10% to 20% premium over the less energy-efficient variable air volume system, the chilled beam system made it possible to lower the PV system cost by $200,000. The elimination of perimeter heating saved a further $150,000. Beauty Is Important in Sustainable and Net Zero Buildings. The Packard Building has garnered so much attention and thousands of visitors because it shows the way to buildings with exceptional performance where aesthetics are not compromised. At no time in the design of the Packard Foundation building was there a trade-off between beauty and performance. The two were meant to go hand in hand from the beginning. The incorporation of biophilia and the use of comfort enhancing strate- gies such as automated and fixed shading systems make the building comfortable, beautiful and a joy to inhabit. Top The lightshelves mounted below the upper windows are also radiant heaters to offset heat losses at the glazing. Above Within the exterior façade lies advanced framing with 24 in. spaced wood studs, continuous mineral wool insulation, and R-19 batt insulation for an overall R-value of 18.2. © Jerem
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