Educational experience: Designing K-12 schools
Engineering work on K-12 schools is complex—and not just because of dwindling school budgets. The facilities must meet a broad range of exacting standards coming from officials and state regulatory bodies, in addition to meeting energy efficiency standards. Here’s a general overview.
- Robert J. Linder, PE, LEED AP, Senior Project Manager, Karges-Faulconbridge Inc., St. Paul, Minn.
- Robert N. Roop, CPD, LEED AP, Principal, Peter Basso Associates, Inc., Troy, Mich.
- Abbas Shirian, PE, CGD, LEED AP, Principal-in-Charge, Lead Mechanical Engineer, Bridgers & Paxton Consulting Engineers, Albuquerque, N.M.
CSE: Please describe a recent K-12 school project you’ve worked on.
Robert N. Roop: One of our most recent projects was for Onsted Community Schools, located in the small farming and resort community of Onsted in south-central Michigan. All of their K-12 buildings (an elementary building, a middle school building, and a high school building) are located in a campus arrangement. Very little had been done to the mechanical, electrical, and plumbing (MEP) systems of the buildings over the past 40 years, and operating expenses were very high. They chose to provide cooling for all educational spaces as the primary goal of their project, so working together we helped them select a ground-source heat pump system for its lower operating expense. We designed a central geo-exchange field to serve all buildings. Piping from the field is supplied to all buildings through central pumps. This configuration lets all buildings share in the diversity of the building loads and increases operating efficiency.
Abbas Shirian: We handled the Rio Rancho Public Schools’ V. Sue Cleveland High School in Rio Rancho, N.M. This project is a new high school building of approximately 400,000 sq ft that accommodates nearly 2,350 students. The school was designed to meet all U.S. Green Building Council LEED Silver Certification standards. The project was designed with sustainable/LEED design concepts, including a ground-coupled heat pump system (640 geothermal wells that are each 305 ft deep). Major school components include classrooms, laboratories, administrative offices, media center, performing arts facility, gymnasiums, food service, playing fields, library, and student and faculty parking areas. The design team developed student circulation patterns within the school based on distances between classrooms to the shared facilities of media center, food center, administrative offices, gymnasium, and playing fields. The school’s main entrance is at the administrative area, on the eastern edge of the building to control and monitor access of students and visitors into the school.
The gymnasium complex and playing fields are located at the western edge of the school building. This location makes it easy for the general public to find when attending an event and also allows the student parking area to be used as special event parking for athletic events. This complex has 69,000 sq ft of indoor athletic spaces, which include a large main gymnasium, auxiliary gymnasium, athletic offices and conference room, extensive storage spaces, concessions, ticket area, physical education classrooms, locker rooms, physical therapy area, wrestling room, and athletic laundry area. The athletic complex will consist of two gymnasiums; a field house; and athletic fields for football, soccer, baseball, softball, track, tennis, and general use. School events at the gymnasium and the performing arts building attract large numbers of spectators. Locating these two buildings at opposite ends of the campus means that it is possible to schedule events in each venue for the same evening and still have sufficient parking and an orderly circulation pattern.
The team worked in tandem with the district’s educational consultant to integrate educational goals and building design. The educational goals for the building environment include: technology access and flexibility, secure school environment, spaces to encourage and support collaborative teaching and learning, personalized learning spaces that engage the student, and an academy concept of a school within the school.
The site plan was developed in conjunction with the Rio Rancho School District representatives, the administrative team for the new school, and community input. The site plan established the footprint for the final buildout, so utility services and traffic roadways were sized and located to accommodate future phases. Phase II classroom additions will be integrated into the school’s circulation pattern from the outset so that a major reorganization is not required when adding classroom buildings in the future. The food service facility (consisting of a cafeteria and food court) is oriented to capture views of the mountains.
CSE: How have the characteristics of K-12 school projects changed in recent years, and what should engineers expect to see in the near future?
Robert J. Linder: We have noticed a trend toward retro-commissioning of building systems in lieu of new design projects. School districts are trying to do more with less, improving operations and energy efficiency while minimizing capital expenditures. It is not uncommon for small remodel design projects to materialize from the retro-commissioning effort. However, the retro-commissioning results typically improve operations enough that the building systems can remain in service and large capital renovation projects can be avoided.
Roop: As new construction of K-12 facilities has evolved from the industrial model of double-loaded corridor classroom buildings toward more agile spaces easily adapted for varied teaching techniques and subject matter approaches, so too must the MEP design evolve and function in this modern approach. Also, in our area, much of the focus on K-12 school projects has been the modernization and renovation of buildings built 40 to 50 years ago. Since these buildings have greater constraints than new construction (i.e., the roof, structure, exterior walls, etc.), there are greater challenges in replicating the same function you can achieve in new construction.
CSE: How do engineering systems in K-12 schools differ from those in colleges and universities?
Shirian: All educational facilities require MEP systems that are functional; meet code; and are efficient, reliable, sustainable, and cost-effective, but K-12 schools for most school districts have several additional concerns, including service from critical vendors and suppliers who may not be local or may be less reliable than in urban settings, and the need to match system complexity and maintenance to the capabilities of less sophisticated operating staff and available vendors. These issues can be more challenging for rural schools.
Roop: Most K-12 school districts do not have the same levels of well-staffed, highly skilled operations and maintenance (O&M) personnel possessed by colleges and universities, so our systems approach must recognize this. The same equipment types and/or system configurations applied as campus standards in the college and university market would be beyond the grasp of the average K-12 maintenance staff and O&M budgets. Conversely, systems regularly applied in K-12 schools are generally regarded to not be robust or durable enough for the higher education clients.
Linder: We are finding that budget limitations have had a great impact on operations and maintenance. An unfortunate consequence is inadequate support for the O&M staff. This includes both reduction in the number of staff and training available for those that remain. As a result, design professionals are forced to limit the amount of flexibility designed into building systems. Instead, design professionals select traditional equipment and simplified control sequences to ease the burden on the O&M staff.
CSE: What types of modeling tools do you use?
Shirian: For energy modeling we primarily use eQuest and Trane Trace 700. Occasionally we use EnergyPro and Ecotect/Green-Building Studio. For daylight analysis we use AGi32 and Ecotect, and for detailed renewable energy systems we have begun to use System Advisor Module, both of which inform energy modeling inputs and assumptions. In some cases we use Window5 to evaluate window assemblies and BLCC5 for lifecycle costing.
Linder: We have a number of energy modeling tools that we use, including Trane Trace 700, EnergyPlus, and IES VE. We select the modeling tool for each project based on the questions we need to answer with the model results. For most of our recent school projects we have used Trace because of its dual strengths as an energy modeling tool and also as a sizing and design tool. This flexibility has meant that we can use the model to answer both questions from the mechanical and electrical design teams as well as questions from the architectural design team or school district. For a recent K-12 project, we provided design assistance energy modeling starting in the schematic design phase. We used an early Trace model to look at the predicted payback of a geothermal system versus a conventional boiler/chiller system, and the payback of several glazing and shading options. We continued to build this model during design development and used the model for sizing plants and systems. Once construction documents were completed, the model was again updated to document LEED points and to apply for utility rebates.
Roop: Our office uses a variety of modeling tools selected primarily for the level of detail, or desired output format. We have standardized on Trane Trace for heating and cooling load calculations as well as energy modeling, though we have also used the DOE-2 in some instances. We have also developed many unique calculation tools in-house to benefit our clients when analyzing system options and costs.
CSE: What unique fire suppression systems have you specified or designed in K-12 schools?
Shirian: A typical fire suppression system for schools is a wet pipe fire sprinkler system. Fire sprinklers are designed throughout using upright heads for exposed areas and pendant heads for areas with finished ceilings. The challenge is when the performance of the municipal water system is evaluated during the design phase and the need for a pressure booster system (fire pump) or a storage tank is required. An alternative to a potential fire pump or pressure booster system may come in the form of municipal infrastructure enhancements that may deliver increased water pressure and volume.