Learning objective: Designing K-12 schools
- David Ellis, PE, CEM, LEED AP Senior Vice President of Engineering Allen & Shariff Engineering LLC Columbia, Md.
- Nestor Ortiz Senior Construction Engineer, Project Officer Parsons Brinckerhoff Long Island City, N.Y.
- John C. Palasz, PE, HFDP Mechanical Engineer Primera Engineers Ltd. Chicago
CSE: Please describe a recent K-12 school project you’ve worked on.
David Ellis: I was involved with the design of a complete renovation of a 330,000-sq-ft high school located in Washington, D.C. This project included a natatorium, performance auditorium, arts center, gymnasium, two kitchens, and academic classrooms, including labs. The high-performance conditioning and ventilation system for this school involved the matching of a hydronic variable refrigerant flow (VRF) system, using a ground coupled approach along with a dedicated outdoor air system (DOAS). Design was performed using a design assist contract, which included a great deal of cost control input from the contractor, as this allowed for an accelerated construction schedule while containing costs. As this was a renovation, BIM software proved valuable for coordination.
Nestor Ortiz: I am the lead project officer for the school construction authority (SCA) construction management for an expansion/renovation of a public school in Queens,N.Y. We are adding 43,000 sq ft to an existing school. The new building will have four floors and a mechanical equipment room located on the roof. This expansion will be connected to the existing school at all three floor and cellar levels. The school will become Americans With Disabilities Act (ADA) compliant as well as provide two elevators, a gymatorium, a new kitchen/cafeteria, eight new classrooms, a music room,a library, a science resource room, and an art room. In case of emergency, the school will be able to run on emergency backup due to its new generator located at the roof level.
John C. Palasz: I was the lead mechanical engineer for a boiler renovation project at Carl Schurz High School. A historic landmark on Chicago’s northwest side, Schurz is a 400,000-sq-ft building housing more than 2,500 students. The project included the replacement of the steam boilers with new 500-hp low-pressure steam boilers with the addition of steam-to-water heat exchangers, two 365-ton centrifugal chillers and cooling towers, as well as all pumps, feed water, chemical treatment, and accessories to provide a dual-temperature water plant. In addition, the air-handling systems were refurbished and retrofitted with new dual-temperature coils, fan motors, filters, and dampers. The project also included all associated controls and a new building automation system (BAS).
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?
Ortiz: There are several safety features that have been added to schools for security reasons, such as cameras throughout the school grounds and designated rescue rooms. Aside from security upgrades, the engineers can expect mechanical, electrical,plumbing (MEP), and fire protection systems that are more self-sufficient and efficient.They will make the school custodian’s life easier as the equipment will be able to communicate if there is an issue or service needed. The equipment will be able to run efficiently, in various modes, such as startup, occupied, unoccupied, and economizer mode.
Palasz: Similar to a number of other markets, K-12 school projects have started to see more demanding design and construction schedules in recent years. Schools and districts are stretching their budgets in multiple directions to cover necessary building repairs, infrastructure upgrades to reduce energy costs, teacher salaries and pensions,utilities, and the desire for improved teaching technologies such as smartboards and computers. As budgets stay the same or decrease and schedules decrease, these projects become a challenge. In the near future, engineers can expect to see an increase in the overall number of projects as aging buildings and rising energy costs drive the need for building control systems and high-efficiency design. The energy codes (International Energy Conservation Code and ASHRAE Standard 90.1) raise the bar for both renovation and new construction projects, but this usually comes with a higher price tag. Furthermore, the long-term energy savings that are designed may not be realized. Commissioning the system after the initial setup as well as regularly scheduled user training can help to achieve or maintain the projected energy savings.
Ellis: Sustainability-in regard to energy-water, and acoustics have taken charge of the design approach. The U.S. Green Building Council’s LEED for Schools program has led to innovation in school design, where measures such as energy-efficient design,water conservation, and a focus on room acoustical performance has improved classroom effectiveness while improving the sustainability of the school project. As certification programs ratchet up performance expectations, along with higher performance sustainability codes, expect the drive to net zero to enter into the next generation of facilities that begin design within 5 to 10 years.
CSE: How does engineering systems in K-12 schools differ from colleges and universities?
Palasz: My experience is that college and university engineering systems are generally designed to encourage student enrollment. Expenses are seldom spared to ensure quiet and comfortable designs while systems are designed with a higher standard of quality. These systems can be designed to last 100 years or more. Additionally,classrooms are designed with more versatility to specifically allow for rapid furniture changes to allow for collaboration one day and independent work the next day. On the contrary, many K-12 projects are limited by budget, and improvements are made to bring the school up to par or code minimums. Budget constraints often limit the design approach, which results in equipment that is expected to last between 20 and 30 years.
Ellis: There are similarities, of course, but in general, along with the discrete focus buildings, as opposed to the combined activities in schools, universities have the potential for campus-wide utilities and the hours of operation tend to be extended. In addition, university operations staff typically have a higher level of training than the staff of K-12 schools.
Ortiz: My work experience has allowed me to work with many types of buildings, but not colleges/universities.
CSE: Please explain some of the general differences between retrofitting an existing school and working on a brand-new structure.
Ortiz: When working on retrofitting an existing school, some of the challenges entail upgrading current utility services (electrical system, water/sewer services, and/or gas service) or having to interface new with outdated equipment. Even with thorough surveying and planning, unforeseen conditions inevitably occur when working in an existing building. When working with a brand-new structure, a critical factor will be complete coordination of trades and compliance with all the latest codes and standards.
Ellis: Existing schools pose a challenge in adapting to existing structural and envelope constraints than that encountered in new school approaches. Usually, there is uncertainty in locating or identifying these existing constraints, and that leads to risk in containing construction costs. As such, renovation projects benefit from having a contractor involved early, providing demolition to reduce the uncertainty during design.
Palasz: Some of the general differences between retrofitting an existing school and working on a brand-new structure are that retrofit projects often require more site survey work prior to construction and are likely occupied during construction. This introduces logistical challenges and requires additional design considerations. New structures allow for increased design flexibility in building shape and system type. That flexibility leads to an increased potential for energy savings from a tighter and more insulated envelope and/or a spacious mechanical room that allows for accessible, sustainable,and maintainable equipment that may be integrated directly into the building type. Older structures seldom offer these opportunities.
CSE: Many schools require flexible space-building features that can be adapted to different uses as the school’s needs evolve. How do you take such requirements into consideration?
Palasz: By gathering as much information about the different uses and coordinating the ways that the space will be adapted, many system types may be eliminated. If different space uses are few and known, then a system can be designed to have various modes to accommodate accordingly, such as a lab mode (using 100% exhaust), lecture mode,or disco mode. To be cost-effective when designing a flexible space, the design requirements must be well-defined. One common approach is to design added capacity in the system to account for high occupancy, or additional computer equipment while incorporating the appropriate controls to reduce or shut off cooling, ventilation, or exhaust as needed. The controls help maintain energy efficiency, but oversizing equipment to account for design flexibility may result in a high installation cost.
Ortiz: My current project includes a gymatorium that is a combination of a gymnasium and auditorium. Aside from the two obvious functions, this space gives the school a location for kids to play on rainy days, a location the community could use for events, or a community refuge from natural disasters. The gymatorium will have its own dedicated rooftop unit and emergency lighting that will be tied back to the school’s new emergency generator. The gymatorium will have chair storage and retractable basketball rims so the school can transition to different sporting setups.
Ellis: Other than the use of combined gyms with assembly lunchroom-type spaces for primary schools, where the biggest concern is the accommodation of differing ventilation demands, there hasn’t been a request observed for the ability to repurpose space, as might be the case with office or flexible laboratory construction.
CSE: What unique tools, software, or systems do you use when specifying systems or designing K-12 schools?
Ellis: Other than dealing with acoustical concerns, which typically involve a separate acoustical consultant, no specific software is employed that wouldn’t be used in design processes for other facilities.