|Stuart Middle School is a LEED Silver Certified project in the LEED for Schools 2007 program. The school is located in a rapidly growing community surrounding Commerce City, Colorado which is just 15 miles northeast of downtown Denver on the edge of the eastern Colorado plains and adjacent to a community park.
The school program required that the building design support the concept of student communities and teaching teams that work together. These communities are achieved by creating core teaching areas or “Core Team Instructional Suites”. There are a total of six “Instructional Suites” within the school, two for each grade level. Each instructional suite contains four teaching stations (including science), a computer lab, student lockers and restrooms. The Instruction Suites are intended to foster team teaching within a small student community. Each core also includes a teacher workroom, a flexible classroom and a resource room. The flexible classroom will be utilized by the core teaching team in a variety of ways for experimental and interdisciplinary learning techniques. “Exploratory” classrooms are provided for a variety of learning experiences including art, business, technology, music and consumer family studies. Other areas within the school include a library, cafeteria with performance area, two gymnasiums, and administrative offices.
The overall building is organized around an east-west spine which provides for a simple, clearly defined circulation system and arrangement of functional spaces. The east- west spine is defined by a west hallway containing the “private” teaching spaces and an east hallway containing the “public” spaces such as gymnasiums and cafeteria. The main entrance is located at the junction of these two main hallways and the administrative offices are directly adjacent to the entrance. The west hallway links three, two-story cores which house the six instructional suites. The suites are arranged to take advantage of north light through large ribbon windows from each teaching space. The exploratory classrooms are single-story with deep overhangs to shade the south facing ribbon windows. Secondary entrances and stairs are located along the hallway between the suites and the exploratory classrooms. Clerestory windows with deep overhangs align the south side of the second floor hallway to provide natural light and views. Openings are included at the second floor to allow borrowed natural light at the main level. The east hallway leads to the main and auxiliary gyms, locker rooms, cafeteria and the music classrooms. This hallway is 2 stories in height with clerestory windows to the south with a large overhang to allow daylight into the space. The gyms and locker rooms are located on the north side of this two story space with interior windows into the rooms to provide borrowed natural light. The cafeteria is located at the end of the hallway and opens to an outdoor commons along the south side. The performance platform located in the cafeteria will be used by the adjacent music rooms and for after school for performances. The location of the administrative offices with the library above at the junction of these two east-west hallways allows for flexibility for after hours use for the library, gyms and cafeteria while limiting access to the other portions of the school.
The Stuart Middle School has many green features that contributed to LEED Silver Certification including:
- Site Design - The location of the building in the southern portion of the 27 acre site allows for over 72.4% of open space for playfields and water quality measures. Water-efficient landscaping will be utilized throughout and irrigation requirements will be accomplished with a non-potable water system from the surrounding community. Alternative transportation will be supported by providing bike racks and preferred parking spaces for fuelefficient vehicles and carpools. The school utilizes the public non-potable irrigation system for all landscaping.
- Exterior building materials were selected for long-term performance, aesthetics, and to provide an energy efficient building envelope. Materials were also selected to achieve a high level of recycled and local content. The exterior of the building is primarily a brick veneer over insulated stud wall back-up or concrete masonry back-up (insulated cavity wall). Certain portions of the building consist of metal (zinc) panels over insulated stud framing. The stud wall back-up assemblies incorporate extra thick insulating sheathing along with batts to increase energy performance. The masonry cavity walls incorporate additional rigid insulation to increase energy performance. The windows are thermal break aluminum frames with tinted, reflective low-e glass. The single ply roof membrane is white in color to minimize heat gain and heat island effect.
- Interior building materials were also selected for long-term performance, aesthetics and to achieve a high level of recycled and local content. The public hallways consist of metal stud partitions with a concrete masonry veneer wainscot. Ceilings consist of lay-in acoustical tile and gypboard. Flooring primarily consists of carpet, vinyl tile and wood flooring at the gymnasiums. The indoor environment will be greatly improved by implementing the indoor air quality (IAQ) program during and after construction as well as the specification of low VOC sealants, adhesives, paints, coatings and carpets throughout. The mechanical system will utilize a CO2 monitoring system which will help ensure indoor air quality as well.
- The heating system utilizes high efficiency condensing boilers designed to operate at a 40 degree heating water delta, and 140 degree supply water temperatures which allow the boilers to operate at their highest efficiencies. The boiler system utilizes the manufacturer’s boiler management system to stage the boilers and modulate the boiler firing rate to maintain the boiler operation at their highest efficiency. This configuration greatly reduces the natural gas consumption of the boiler system. The boiler system also incorporates variable speed pumping systems to allow the heating water system to operate at only the water flow necessary to maintain space temperatures. By utilizing variable speed pumping systems, the electrical demands of the heating system are reduced. The heating system also incorporates a heating water supply temperature reset schedule. This allows the heating system to operate at a variable heating water supply temperature so the system provides a heating water temperature which is most efficient for the heating system.
- The cooling system for the building utilizes an air cooled chiller supplemented with an ice storage system. The ice storage system is designed to operate at night when energy consumption rates are significantly lower. This in turn allows the cooling system to operate from the stored ice to generate the chilled water necessary to maintain cooling within the building during the day. The pumping system utilizes a variable speed pumping configuration which allows the system to operate based on the quantity of chilled water necessary to maintain space temperatures. The chilled water system also incorporates a temperature reset schedule which allows the chilled water supply temperature to be adjusted to operate at a temperature which is most efficient for the system.
- The ventilation system incorporates carbon dioxide sensors to allow for modulation of the outside air provided for each of the rooftop units. These sensors allow the units to operate at outside air volumes which are required for the actual occupancy of the building. Each air system incorporates these sensors, which allows for diversity in the system to accommodate occupancy movements through the building. By specifying refrigeration equipment which complies with the requirements outlined in the refrigeration reduction protocols the project utilizes only environmentally friendly refrigerants such as R-404 and R-410a. Thermal and lighting controls have been incorporated to increase occupant comfort. The air distribution system utilizes carbon dioxide sensors to monitor the carbon dioxide levels at each air handling system. These sensors are not only used to modulate the outside air to incorporate energy efficiency but are also used to modulate the outside air to provide fresh air to the distribution system in response to occupancy levels within the building.
- In addition to reducing the amount of potable water used through irrigation, the building plumbing fixtures such as lavatory faucets and shower heads will save approximately 37% over the Energy Policy Act’s baseline. The spaces which produce objectionable odors and other pollutants have been isolated to provide additional occupant comfort and improve the educational processes. Rooms such as janitor’s closets, copy rooms, etc. utilize exhaust systems to maintain a negative pressure to the adjacent spaces. Additionally, the construction of the spaces helps to provide separation between the adjacent occupied spaces. The HVAC air distribution systems have been designed to provide thermal comfort. The systems have been designed utilizing the requirements as outlined in ASHRAE. By incorporating these requirements the HVAC system has been designed to allow for a minimum of 80% occupant comfort. This design process will be verified after a given period of time to confirm the design meets the minimum occupant comfort.
- Electrical Features - In addition to the aforementioned electrical reductions associated with the mechanical systems, the design incorporates high efficiency lighting fixtures throughout. The lighting system for all of the general classrooms has been designed to incorporate natural daylighting and the light fixtures are controlled by sensors and the building’s energy management system. This system is designed to automatically modulate the electric light levels based on energy use and the time of day.