Valley View Middle School

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Building at a Glance Valley View Middle School Location: Snohomish, Washington Owner: Snohomish School District Architect: Dykeman Civil Engineers: Harmsen & Associates, 2020 Engineers

Includes: Geothermal heating, 90% heat recovery, displacement ventilation, natural cooling, radiant heating, rainwater harvesting, and advanced lighting and controls Employees/Occupants: 100 staff/

2012 Original Budget: $60,300,000 Total Cost: $59,805,429 National Distinctions/Awards: 2015 ASHRAE Technology Award AIA Washington Council 2014 Civic Design Merit Award 2014 US Glass Green Design

1 Building at a Glance Valley View Middle School Location: Snohomish, Washington Owner: Snohomish School District Architect: Dykeman Civil Engineers: Harmsen & Associates, 2020 Engineers Mechanical/electrical engineer: Hargis Engineers Structural Engineer: Coughlin Porter Lundeen Landscape Architect: Cascade Design Collaborative Principal Use: Public middle school, grades 7 & 8 Includes: Geothermal heating, 90% heat recovery, displacement ventilation, natural cooling, radiant heating, rainwater harvesting, and advanced lighting and controls Employees/Occupants: 100 staff/ 950 students Square Footage: 168,000 sf Unconditioned Space: 19,062 sf Substantial Completion/Occupancy: Sept Original Budget: $60,300,000 Total Cost: $59,805,429 National Distinctions/Awards: 2015 ASHRAE Technology Award AIA Washington Council 2014 Civic Design Merit Award 2014 US Glass Green Design Award CEFPI Exhibition of School Planning & Architecture, Project of Distinction Excellence in Masonry Design Award Merit Award K-12 By Brian Haugk, PE, LEED AP; Brian Cannon, PE, LEED AP Valley View Middle School (VVMS) in Snohomish, Washington is a new three-story, 168,000 sf facility that replaced a much smaller and outdated building. Mirroring the district s commitment to resource conservation, the design team used the Living Building Challenge as a guide for defining its sustainable approach. The team strategized on harnessing the greatest contributors to resource conservation: renewable energy sources to be implemented; capturing and reusing emitted energy to offset draw from the grid; reducing consumption through system selection; and supporting behavioral changes inspired through monitoring and reporting. The school, owned by the Snohomish School District, houses 950 students and uses less energy than the previous 1981 school that was half the size. About the Authors Brian Haugk, PE, LEED AP is a principal and Brian Cannon, PE, LEED AP is an associate principal at Hargis Engineers in Seattle, Washington. Design Collaboration The project was the first for the district to consider the Living Building Challenge for a Net Zero-ready school. At the time, schools built prior to Valley View were too new to have adequate data to provide a benchmark for previous sustainable initiatives the district was enhancing and implementing. It also presented an opportunity to further define and measure its sustainable approach goals, objectives and performance. The district s sustainable management goals balance and encompass facilities, operations and health of the building s occupants. Their approach incorporates 1) using durable materials and integrating building components and systems to withstand the wear and tear, 2) targeting a 50-year plus life cycle, 3) reducing maintenance and operations costs, 4) reducing the use of resources and energy consumption beyond code and state requirements, and 5) provide excellent indoor air quality and comfort. They also wanted to create a space embraced by the community. A committee was engaged to represent a cross-sector of community and school district stakeholders. Street presence, maximized views, View of the classroom wing with daylight harvesting and rooftop water collection system in bottom left-hand corner. classroom orientation for optimum daylighting, promotion of community use after-hours, functionality, visibility and security were articulated design criteria by this group. Community-accessible spaces were configured within the campus to accommodate outdoor athletic fields, two gyms, commons area, library and lecture hall. Applying the functional goals, the professional team developed options for meeting the performance and program- Aerial of site (August 2012) w/ overlay of pre-existing buildings. For energy consumption the old buildings used 1,325,514 kwh/yr combines while the new building only uses 1,239,965 kwh/yr.

System Attributes Benefit Power 960KW PV-ready Provides net-0 energy usage Renew Heating/ Cooling Geothermal Uses free cooling of the Earth Ventilation 90% heat recovery Energy efficiency

2 System Attributes Benefit Power 960KW PV-ready Provides net-0 energy usage Renew Heating/ Cooling Geothermal Uses free cooling of the Earth Ventilation 90% heat recovery Energy efficiency Displacement ventilation Heating/ Geothermal Exchanges heating/cooling energy Cooling Reuse Water Rainwater harvesting with 75,000 gal. central tank All urinals & water closets served through system Reduce LIGHTING LED fixtures Daylight harvesting Automated dimming controls Occupancy sensors Automated motorized shades Optimized window configuration for natural daylighting Energy usage is minimized through an integrated lighting and shading strategy Occupant comfort and convenience Occupant required interaction with system is removed Energy reduction; performance based on payback for solar panel array BUILDING ENVELOPE Roof = R-60 Walls = R-48 Windows, Triple Glazed, U = 0.24 HEATING Centralized water-to-water heat pump using geothermal wells Passive heating by convectors and radiant floor Maintenance costs reduction Energy reduction Reduce fan energy with passive heating System efficiency HEATING (DOMESTIC) Water heaters Energy management system (EMS) controlled COOLING Geothermal well temperature Compressor energy reduction Figure 1: Valley View Middle School hydronic and air system Overview VENTILATION Displacement ventilation Variable air volume (VAV) units Increase economizer range from 55F to 72F No fans/filters with VAV units Minimize fan and pump energy Variable fan speeds with capabilities to reduce by 50% Energy reduction in operations matic objectives. Building placement played an important role in influencing the design approach and upholding the conservation goals. Energy Efficiency The school capitalizes on strategic approaches to maximize system efficiency and reduce the overall building energy consumption. These can be divided into three main categories: Reduce - infusing higher efficient systems that align with performance objectives Reuse redirecting typically wasted energy/resources back into the building s operations Renew - introducing new sources to the site without requiring further demands on mass utilitie. The following Table 1 outlines the energy conservation approach in relationship to the school s triple bottom line. Note over the last year the school operated at 26 EUI. Fan/pumps Variable primary pumps Fan wall technology ECM fans or VFD Kitchen Energy Star rated kitchen residential appliances Power Use thin client computers Network-based server software METERING Electrical meters Domestic water Gas meters Computer power load reduction within the building Security of network Reduction in electrical loads and computer loads Creating a virtual environment

Innovation The geographical location presented opportunities for technical innovations for this type of facility. Sited in western Washington, this building is predominantly in a heating environment.

3 Innovation The geographical location presented opportunities for technical innovations for this type of facility. Sited in western Washington, this building is predominantly in a heating environment. Year after year of continuous heating operation will slowly lower the temperature of the ground degrading the capacity to absorb heat from the ground, impacting the efficiency of the water-to-water heat pump (WWHP). As part of the design, cooling loads were used to offset this inherent load imbalance, the 24/7 cooling spaces (main electrical, distributed transformer rooms and MDF and IDF telecom spaces) are all served by a separate, central plant system to effectively recharge the ground loop. Immediate impacts of this approach will not be seen as the temperature change of a well field is subtle, providing long term energy savings. The ground loop return water temperatures are being monitored. Capitalizing on Thermal Dynamics of Water TheWWHP/displacement ventilation (DV) system combination affords greater control in maintaining occupant comfort. This project was one the first to use this product in the region and fully integrate the factory controls with the building EMS. The ground source heat pump system was sized for 100% of the central plant heating and cooling capacity. Integrating the WWHP was critical to the DV approach, as it requires very tight discharge air temperature (DAT) control to maintain occupant comfort. At the time this article was written, water-to-air heat pumps on the market were unable to achieve the DAT control required. Reducing Energy, Improving IAQ The classroom DV system utilizes a custom toe kick space supply grille under the casework as opposed to conventional grilles provided by major manufacturers. CFD model simulations and actual installed systems have vetted this custom approach that improves the integration in a typical classroom layout. Convectors were used at the exterior under the windows. The library integrated benches at the windows with DV as well as internal wall style conventional DV grilles. The DV system in the administrative spaces utilized wall DV manufacturer style grilles with radiant floor at the perimeter. Customizing and Integrating Low-traffic Spaces An opportunity was identified to utilize energy efficiency in toilet rooms, staff break rooms and copier rooms. General exhaust fans serving these spaces are interlocked with lighting control systems occupancy sensors to control the exhaust fans operation. Systems that provide exhaust for multiple spaces include motorized dampers that isolate the unoccupied spaces and have either VFDs or ECM motors to control fan speed for the variable exhaust volumes. This approach also optimized the quantity of air going through the heat recovery system. A screenshot of the Competition Zone dashboard that can be accessed by any staff member to see, in real time, the direct effects of their room s energy consumption vs other areas of the campus. Operations and Maintenance Both the maintenance and repair/replacement costs for the O&M for the final design are at least 10% better than any of the alternative options including the ASHRAE 90.1 baseline with 50% heat recovery. Strategies that fueled these results include:

centrally located at the main air handlers Eliminated fans utilizing VAV boxes without filters in the system Filters are 12 deep to minimize scheduled filter changes Utilizing direct drive fans to

4 Figure 2: Metering for of the campus energy usage by category over the course of a week in October of 2013 to support Cx process. Considerations Analyzed Total utility usage Total cost of ownership of the school Replacement cost and regular maintenance costs Enhanced Optimization Opportunities Based on Review All filters are centrally located at the main air handlers Eliminated fans utilizing VAV boxes without filters in the system Filters are 12 deep to minimize scheduled filter changes Utilizing direct drive fans to avoid belt-driven fan maintenance Larger AHUs utilizing fan wall technology Design Options Comparison 4 alternative systems ASHRAE 90.1 baseline with 50% recovery Washington State Energy code baseline Final design Total Cost of Ownership Total cost of ownership was a driving factor in the sustainable discussions. The district was savvy to understand that while sustainable systems are possibly more expensive upfront, they can reduce a building s lifetime operating costs significantly. First costs for construction on the ground source WWHP, VAV reheat, radiant floor heating and 90% effective energy recovery unit systems was the greatest value to the owner. Energy usage and costs show the district would end up spending less money on annual utility and maintenance costs Figure 3: Lowest 30 yr life cycle cost and lowest EUI (Alt No. 2) compared to ASHRAE 90.1 Baseline Alt No.1. Alternate options not shown. compared to the alternative with no first-year cost. The alternative exceeds the cost effectiveness in total yearly costs, as well as a Washington State required 30-year life cycle cost analysis when compared to other systems. Total cost of ownership was reviewed to ensure that the sum of the lowest maintenance and energy costs combined would be realized. $101,244/yr 57 EUI Code Baseline COST SAVINGS 26 EUI Alternating Currency Indoor Air Quality and Thermal Comfort Upholding the district s fifth goal for occupant comfort, the DV system was adopted. The DV system is a proven approach to enhance energy performance through an extended economizer range and reduced fan energy while improving indoor air quality. Hargis designed and is tracking the performance of these systems in 40+ K-12 schools constructed since Air is supplied down low, conserving energy by only heating or cooling the air near the occupants. The introduction of fresh air and removal of pollutants at the ceiling level is at a minimum, 50% better than a comparable overhead air distribution system. Specifically, a district where Hargis has completed six schools to date with DV, have also shown 3-6% improvement in attendance that can be attributed to a healthier building due to improved ventilation. DV also exceeds the noise criteria dictated by the Washington State health department. From a sound level code value of NC-35, the teaching environment is improved to a NC level less than 20. Enviromental, Social and Behavioral Impact Responsive to constituents adoption of sustainability, public institutions are using facilities as an opportunity to express their conservation philosophy and commitment. Environmental design elements utilizing integrated strategies included reduced energy demand via envelope design, solar technology, geothermal technology, rainwater harvesting and integrated value messaging. The school fulfilled the community s criteria, as well as becoming a source of operational efficiency for the district. The district utilizes VVMS to host a majority of the off-hour functions as energy and maintenance dollars are approximately half of the district s other comparable pre-1990s facilities. The following Table 2 outlines the environmental components and their contribution to the sustainable development An EMS-based energy dashboard system with touch screen monitors at multiple locations allows staff and students to learn about the sustainable features of the building. The system is also webbased, allowing faculty to use the system as a teaching tool. To further spark students interest, the EMS metering design of the lighting, plug and HVAC systems allowed for competitive zones to be created in six classroom pods. This allows students to interact with the building systems to see Barrels of crude oil that will not be consumed per year. Football fields worth of dense forest planted every year. Homes unplugged from the electric grid for a year. 640metric of tons CO2 Actual Usage = A reduction of 1,581,951 kwh per year or 640 metric tons of CO 2 emissions.

throughout the life cycle of the building to inform and guide generations of children and staff that pass through its doors, providing them with a better understanding of their environment well

5 throughout the life cycle of the building to inform and guide generations of children and staff that pass through its doors, providing them with a better understanding of their environment well beyond the team s M&V involvement. Valley View Middle School: Site Characteristics & Building. Environmental Components Contribution Fossil Fuels Natural gas was limited to science and vocational requirements, otherwise not used as a heating source Infrastructure for a future 960 kw PV array installed Ground loop well field sized for 100% of the load, allowing removal of any gas fired HVAC equipment CFCs No CFCs were used on this site Only refrigeration equipment is at the WWHP, elevator machine rooms AC units & kitchen cooler/freezer Waste All waste is treated on site through a septic system. A future living machine for providing potable water can be installed in the future. Water Low-flow plumbing fixtures were utilized A rooftop rainwater collection system with a centralized system that can store 75,000 gallons of non-potable water for use in flushing water closets, urinals and irrigation. Other storage units around the building, with a total capacity exceeding 200,000 gallons. (Enough water to fill 4,000 average sized bath tubs or support the daily water usage of an US family of 4, for nearly a year and a half) Recycling & Concrete from the original building was reused as a sub-base for driveways Reuse Storm water management and parking areas. The largest pervious pavement installation in the northwest filters water directed to onsite wetlands. what kind of impact they have on the overall energy usage. The dashboard was also integrated with the support of the staff to allow for the integration of lunch menus, sports scores, way-finding, school events, etc. Committed to energy conservation and the sustainability of the site, the interaction of competitive zones and interpretive signage throughout the school are being used as a teaching tool to educate occupants on the sustainable design elements and new technologies integrated into the building and site. These teaching components will continue

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Carbon Neutral 60% 70% 80% 90% Today 60% 70% 80% 90% Carbon Neutral Today 2015 2020 2025 2030 Fossil Fuel Energy Consumption Fossil Fuel Energy Reduction GBD Architects LEED PLATINUM + NET-ZERO ENERGY Location Hood River, Oregon Building