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The Highlands Center For Natural History JAMES LEARNING CENTER. Winner of the 2010 AIA Sustainability Award Prescott’s First LEED Certified Building First LEED-GOLD in Yavapai County. View of south façade at dusk. site-sensitivity.
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The Highlands Center For Natural History JAMES LEARNING CENTER Winner of the 2010 AIA Sustainability Award Prescott’s First LEED Certified Building First LEED-GOLD in Yavapai County View of south façade at dusk
site-sensitivity A Site-Sensitive ApproachAs an environmental stewardship organization, a site-sensitive approach for the building's placement on the land was imperative.Leaving the majority of the 80 acre site undisturbed for hiking trails, as well as to protect existing plant and animal habitat, was an essential consideration.A small clearing near the existing structures and parking lots, with favorable solar access, and an east-west orientation (for passive solar optimization) was ultimately chosen for the Learning Center building pad.Plan at right shows only the developed portion of 80 acre property (approx 6 acres). NOTE: Site is heavily wooded– not all trees are shown. LEGEND James Learning Center Natural detention glade Sidewalks (existing) Parking lot (existing) Amphitheater building (existing) Interpretive sculpture Restroom building (existing) Water storage tank (existing) 5 6 7 8 north
contextual design 4 5 A Natural ContextThe 80 acre site was provided to the Highlands Center as a long term lease from the Prescott National Forest.Careful integration with the existing buildings, as well as with the densely forested site, was a paramount consideration for the building’s placement and design.Though the new building form is a dramatic departure from the existing structures, similar materials, finishes and colors (wood, stucco, and metal roofing), help contextually integrate the new building with its surroundings. Designing With Nature The vertical log support structure echos the many pine trees which surround the building site (image below & left). 3 1 2 LEGEND Existing Restroom Bldg. (from building pad, looking SE) Existing Amphitheater Bldg. (from Bathroom bldg., looking SE) East roof edge drainage point (looking SW) South façade (from Amphitheater Bldg., looking NW) West façade (from highway access point, looking East) 4 5 1 2 3
space–efficiency High Efficiency + Maximum FlexibilityDevelopment of the floor plan focused on achieving a maximum efficiency of space usage, with a minimum of single-use corridor or hallway space. Flexibility within the administrative areas was also a key concern, as evolving programs required adaptable staff and volunteer work areas, space arrangements and relationships.South facing stone interior walls (denoted in red) constructed with rock collected on site, provides efficient thermal storage for the low-angle solar gain available during the coldest months.The curvilinear south exterior wall helps visually tie the building to the organic forms found on the site. north
integrated high-performance CAD model showing primarymechanical and structural systems High-Performance DesignDiagrammatic section at right shows the integrated high-performance design systems of the James Learning Center.Operable clerestory windows north and south, sized for maximum solar gain and daylight contribution (with minimal heat loss), also serve to ventilate the building when needed. A south facing interior stone wall, built from rock harvested on site, stores solar heat during the cold winter months, warming the building and stabilizing indoor temperatures. Deciduous vines trained over the lower south-facing windows, allows sunlight into the building during the winter, while shading out solar gain during the summer.Reflective light shelves north and south help bounce additional daylight into the interior of the building. Section looking west through Welcome Center/Bookstore and Mult-Purpose Classroom LEGEND Radiant heat in 5” stained concrete floor Locally harvested tree poles South facing 8Kw photovoltaic array Light shelf and mechanical plenum Operable windows for daylight, views and ventilation Deciduous vines on trellis for summer shading Light shelf (in front and behind trellis) Operable clerestory windows for natural daylight and ventilation Inverted roof for rainwater catchment Natural stone wall for thermal storage 6 7 8 9 10
South façade from southeast corner organic design High-Efficiency In An Organic FormThe exterior form of the James Learning Center is intended to address several needs. First, as a demon-stration facility, the primary function of the building is to teach (via example). Towards that end, both the design team and client agreed that as a teaching instrument, the building must strive to capture not only ones attention, but ones imagination as well.The soaring lines of the butterfly-shaped roof appear as if poised for flight. This organic design, however, also serves other more practical purposes, namely that of creating space for the north and south clere-story windows, as well as providing a very visible rain-water collection device. An Expression of ValuesComputer modeling established the precise curve of the roof in order to provide effective shading for the clerestory windows during the cooling season, while allowing solar gain to penetrate the upper windows during the winter heating season.An organically shaped south wall expresses the environmentally rooted mission of the Highlands Center organization. View of building from southwest
light & warmth Left: Natural stone wall inWelcome Center/Bookstorelooking northwestFar Left: Multi-PurposeClassroom looking northeast The interior spaces were designed for maximum comfort and flexibility. A linear storage bay along the south wall provides ample table and chair storage for the Learning Center’s diverse program needs. Louvered storage doors help distribute heat from the adjacent interior thermal mass stone wall into the classroom area.Dimmable fluorescents, along with north-facing clerestory and eye-level windows provides an even, well-lighted interior. Natural woods, a 5" thick stained concrete floor, and soft earth tones create a warm, comfortable environment for learning. Reception Area clerestory windows Multi-purpose Classroom looking southeast
green details Tree-Huggin' Details By HandHand-made artwork and custom resource-conserving details and can be found in and around the James Learning Center: 1234 Dark-sky compliant custom exterior light fixture (Artist: Royce Carlson) Custom metal rainwater catchment at east end of building (Artist: Royce Carlson) Typical wood bracket detail at post top (along south roof edge)Interpretive, interactive brass sculpture “Equipoise” (Artist: Heather Johnson) 1 3 4 2
off-the-shelf sustainability OFF-THE-SHELF SUSTAINABILITY& TRANSFERABILITYWhile the exterior of the James Learning Center was purposefully unique, it was also our client’s intention that visitors to the Highlands Center be able to learn about sustainable design strategies that could realistically be integrated into their own home or business.In response to this, the James Learning Center employs numerous “off-the-shelf” sustainable design and building technologies that could easily be incorporated into a private home or business. These include: • Proper building orientation • Passive solar design • Thermal mass • Natural daylight and ventilation • Directionally appropriate glazing • 2 x wood framing (smaller structures only) • Locally harvested materials • Rainwater harvesting • Water-saving plumbing fixtures • Native plant selection • Non-Toxic materials & finishes
water efficiency Water Conservation Strategies (Building and Site)Water is one of the most critical development issues in the southwest. In response, the James Learning Center utilizes several water savings strategies both inside and outside of the building. Among these are: Innovative Water Conserving Design FeaturesThe butterfly roof stands out as the most memorable design element of the building. As stated previously, the dramatic roof shape functions not only to collect rainwater, but to educate– by raising awareness of the preciousness of water as a vital resource. At the center of the butterfly roof valley, a large “cricket” helps channel water out towards both the east and west ends of the building, where the flow is then captured into large collection funnels, and then directed into the landscaping. The plant life which relies on this water includes the deciduous vines which play an active role in shading the building during the summer cooling season. • Low water-use plumbing fixtures • Constructed wetlands for wastewater treatment • Rock weirs to slow runoff, control sedimentation, and encourage recharge • Meandering runoff for self-watering landscape • Minimized exterior hardscapes • Use of native, low-water plants to restore disturbed areas • Drip irrigation used only for establishment of plants (or during drought conditions) • Butterfly roof shape provides rainwater catchment for landscape irrigation Water Catchment Device
natural daylight & ventilation Lighting QualityThe lighting system for the building is primarily composed of natural daylight. Reflective light shelves, exterior hardscape, interior and exterior soffits, as well as finished ceiling materials were selected based on their ability to maximize the amount of natural daylight that could utilized within the building’s interior. This design effort directly reduced the amount and size of powered lighting that was then required. Dimmable fluorescent strip lighting makes up the majority of the powered lighting within the building, which is manually controlled, when needed, by the Highlands Center staff. Overall electrical and lighting considerations played an important part in the conceptual orientation and design of the building. Since 100% of the building’s power comes from the Learning Center’s 8Kw photovoltaic solar array, every energy drawing item within the building had to analyzed for its anticipated electrical draw. All lighting systems, equipment, appliances, and computers were considered, and then re-considered in light of their potential electrical needs. Thermal ComfortThermal comfort was addressed early on in the design process by taking full advantage of proper solar orientation. An east-west alignment for the building, along with windows precisely sized and placed for optimum passive solar gain contributed the structure’s highly-efficient energy performance. Operable clerestory windows stack functions by admitting solar gain and providing ventilation. The upper roof overhang provides shading for these windows during the summer, while vine covered trellises provide shading for the eye-level windows below. The building envelope itself is insulated with an R-28 blown-in cellulose in the walls, and an R-34 spray-foam insulation in the roof. Thermal mass is provided by a 4” thick natural stone (interior) wall veneer, as well as in the 5” thick stained concrete floor slab, helping to keep the Learning Center’s indoor temperatures comfortable and stable throughout the year.
resource conservation Local Materials UsedLocal materials used include tree poles which provide the main vertical structural support of the building, natural stone used to create thermal mass inside the building, as well as concrete block used to create stem walls and the earth sheltered retaining wall, located along the north side of the building. Regionally manufactured products include the standing seam metal roof, as well as the evaporative cooling units which were each fabricated in the metropolitan Phoenix area. LEED credits for Storage & Collection of Recyclables, Construction Waste Management, and Local & Regional Materials all contributed to the overall resource conservation qualities of the building. Innovative Resource ConservationOne of the more innovative resource conservation strategies employed on the James Learning Center is the building-integrated use of plant materials for solar control. The use of these deciduous vines along the south side of the building (see CAD model image at right) eliminated the need for a more expensive, resource intensive solution, that would have required actual roof overhangs, or other constructed forms to provide. Our use of these plants materials for solar control on the James Learning Center required only a light gauge metal frame, steel cable, and some water collected from the roof. Shading perfomance CAD simluation for vine covered trellis
ecological impact Minimum Ecological ImpactAs an environmental stewardship organization, our client’s value of building lightly on the land was of paramount importance. The selected site did not require the clearing of any additional land, nor was a single tree removed for the construction. The building pad location was selected based on its proximity to the existing developed areas of the property, as well as within an existing clearing. LEED credits for Erosion & Sedimentation Control, Reduced Development Footprint, and Minimized Site Disturbance were all earned for this project.On a more global level, minimal ecological impact was achieved through the use of renewable (solar) energy which supplies 100% of the building’s electrical needs, as well as through the used of recycled, locally harvested, and regionally manufactured products. No refrigerant cooling was used in the building, as the Learning Center also earned LEED credits for CFC Reduction and Ozone Depletion. Features Relating to SustainabilityBecause the building was to be off-grid, many of the energy-efficient strategies selected were employed out of sheer necessity. The most striking feature of the design, its “butterfly” roof, addresses several energy-saving strategies at once; providing the high clerestory windows for natural daylight and flow-through ventilation, as well as for passive solar optimization of winter-time solar gain, and summer-time solar shading. Combined, these energy efficient design strategies allow almost 70% of the building’s heating and cooling needs to be supplied passively. Another architectural feature of the design that provides for energy-efficiency are the building’s wood and metal trellises (images at right), positioned over the lower, eye-level windows along the structure’s south elevation. These engineered trellises were designed to support deciduous vines, allowing sunlight to penetrate these windows during the winter months, while shading them during the summer. The Learning Center’s appearance therefore takes on an intentionally different look throughout the year, as the building exterior literally “responds” to the seasons.
heating & cooling systems Mechanical System SelectionSignificant contribution of the passive design elements of the building (quantified through Energy Modeling of the building) allowed a sizable decrease in the size and type of mechanical systems required to heat and cool the building. Additionally, energy systems constraints, as well as owner/occupant values and comfort needs, also helped determine the final mechanical system selection. As an environmental organization attuned to outdoor experience, neither the executive director nor support staff of the organization required, (or desired) refrigerant cooling, for example. The design-to temperature for the winter heating season was a modest 68°, with a summer design-to cooling temperature of 78°.This less-demanding comfort zone requirement, combined with the passive energy contributions of the building itself, pointed towards variable-speed control evaporative cooling, and in-floor radiant heating as the appropriate heating and cooling system options for the James Learning Center. Life Cycle Considerations Life cycle cost considerations relative to the mechanical system choices for the Highands Center are consistent with the values of the organization for choosing high durability, low-replacement cost systems. The selected boiler’s lifespan, of between 25-40 years, combined with the life span of the PEX radiant in-floor tubing (between 50-100 years) is higher than comparable forced air systems. On the cooling side, evaporative cooling boasts one of the more favorable life cycle cost scenarios, as both first cost and annual operating cost are much lower compared to a typical refrigerant cooling system. Real-Time Computer Simulated Solar Modeling Evaporative coolers located on north side of building
energy modeling Energy Simulation AnalysisResults of our energy simulation analysis are summarized in the table and chart at right. In all, the Highland Center for Natural History will achieve $2,350 (66%) in annual utility savings per year as compared to a minimally compliant ASHRAE 90.1 building. Approximately 50% of the energy savings on the building can be attributed to the 8Kw photovoltaic system, which has been designed to provide 100% of the building’s electrical needs.Initial energy modeling demonstrated that, based on the quantifiable amount of passive heating and cooling contribution of the building itself, just how little supplemental heating and cooling would actually be needed. Graph at right illustrates the expected amounts of radiant heating (red bars) and evaporative cooling (blue bars) needed on throughout the year on a month to month basis. Mechanical System Energy RequirementsTotal building system energy requirements from graph at right are as follows: Space Heating: 11,900 BTU/ sq.ft./ year Space Cooling: 00BTU/ sq.ft./ year Fans: 400 BTU/ sq.ft./ year Pumps/Aux: 1,500 BTU/ sq.ft./ year TOTAL 13,800 BTU/ sq.ft./ year The 13,800 BTU/ sq. ft./ year energy requirement is roughly one-fifth (1/5th) the typical energy required for a conventional commercial building of similar size. Energy End-Use Simluation Model Heating & Cooling Operation Mode
LEED-Gold Summary The James Learning Center was awarded a LEED-Gold certification in February 2008, making it the first LEED certified building in Prescott Arizona, as well as the first LEED-Gold facility in Yavapai County. Below is a summary of the credits earned in each of the six LEED categories. MATERIALS & RESOURCES Prq_1 Cr_2.1 Cr_2.2 Cr_5.1 SUSTAINABLE SITES Prq_1 Cr_1 Cr_4.2 Cr_4.4 Cr_5.1 Cr_5.2 Cr_7.1 Cr_8 Erosion & Sedimentation Control Site Selection Alternative Transportation- Bicycle Support Alternative Transportation- Carpooling Open Space Protection & Restoration Reduced Development Footprint Heat Island Reduction Light Pollution Reduction Storage & Collection of Recyclables Construction Waste Diversion 50% Construction Waste Diversion 75% Local & Regional Materials INDOOR ENVIRONMENTAL QUALITY Prq_1 Prq_2 Cr_2 Cr_4.1 Cr_4.2 Cr_4.4 Cr_6.1 Cr_8.1 Cr_8.2 Minimum IAQ Performance Site Selection Environmental Tobacco Smoke Control Ventilation Effectiveness Low-Emitting Adhesives & Sealants Low-Emitting Paints & Stains Low-Emitting Composite Woods Controllability of Systems Daylight- 75% of Spaces Views- 90% of Spaces WATER EFFICIENCY Cr_1.1 Cr_2 Cr_3.1 Water Efficient Landscaping Innovative Wastewater Technologies Water Use Reduction ENERGY & ATMOSPHEREPrq_1 Prq_2 Prq_3 Cr_1 Cr_2.1 Cr_2.2 Cr_2.3 Cr_4 Fundamental Building Commissioning Minimum Energy Performance CFC Reduction in HVAC & R Equipment Optimized Energy Performance Renewable Energy 5% Renewable Energy 10% Renewable Energy 20% Ozone Depletion Typical trellis detail at south façade of building INNOVATION IN DESIGN Cr_1.1 Cr_1.2 Cr_1.3 Cr_1.4 Cr_2 Sustainable Education Program Geen Maintenance Polices Exceed Renewable Energy (40% +) Exceed Energy Performance (65% +) LEED™ Accredited Professional
acknowledgements LEED-GOLD PROJECT TEAM STRUCTURAL ENGINEERING Sandy J. Herd, PE CARUSO TURLEY SCOTT, INC. Tempe, AZ PHOTOVOLTAIC DESIGN Ben Mancini EV SOLAR Chino Valley, AZ CLIENT Nichole Trushell, Executive Director HIGHLANDS CENTER FOR NATURAL HISTORY Prescott, AZ MECHANICAL ENGINEERING Pete Kunka, PE KUNKA ENGINEERING, INC. Phoenix, AZ LEED CONSULTING Mark Wilhelm, LEED-AP GREEN IDEAS, INC. Phoenix, AZ ARCHITECTURE Matthew Ackerman, LEED-AP AIA CATALYST ARCHITECTURE, LLC Prescott, AZ LANDSCAPE ARCHITECTURE Barnabas Kane, ASLA T. BARNABAS KANE & ASSOCIATES Prescott, AZ ELECTRICAL ENGINEERING Robert T. Haines, PE HES CONSULTING ENGINEERS, INC. Prescott, AZ LEED DOCUMENTATION Patricia Olson, PhD LEED-AP ECOLOGICAL BY DESIGN Prescott, AZ ENERGY MODELING & COMMISSIONING Henny Van Lambalgen, PE CEM QUEST ENERGY GROUP, LLC Tempe, AZ CONTRACTOR Tom Haley, LEED-AP HALEY CONSTRUCTION, CO. Prescott, AZ LIGHTING DESIGN Richard Landry, LEED-AP IESNA RTL DESIGN, LLC Chandler, AZ
Truly you have created a building that is a magnificent marriage of form and function. I know that I am proud to have been on the board that chose your design. I send you and your team a heartfelt THANK YOU. With deep gratitude, - Joan DukesHighlands Center for Natural History Board Member View of south façade at dusk