What is the student capacity of your facility? Knowing the answer to this question is essential.
How student capacity is determined depends on many factors. Schools built 20 years ago were designed to use space differently from those constructed today. Programs change, school board policies are revised, facilities are remodeled, ventilation requirements altered, and special programming expanded. Pedagogy, delivery systems and staff planning approaches evolve.
To calculate capacity, understanding two fundamental terms is essential: Design capacity is the number of students for which a facility was originally designed. A typical comment is, “The school was designed for 1,000 students—40 classrooms with 25 students per class.” Using this number years later is misleading and may be troublesome when explaining to the public the need for more space.
New directions in pedagogies, class sizes, and programs are different from when the school opened. Spaces needed to carry out new directions in learning are frequently inadequate in older buildings; reconfiguring spaces to support these directions affects capacity.
Program capacity is the number of students effectively supported by the educational program delivered in a facility. Renovations and reconfigurations of space tend to reduce original design capacity. Using program capacity is a more accurate way to determine a facility's student capacity.
Determining capacities for primary schools is more straightforward than for secondary schools; secondary schools must take into account more complicated daily schedules. Primary school capacity is usually derived from the number of learning spaces, class sizes, and core spaces (e.g., gym and cafeteria seating).
Secondary school capacity is derived from a master schedule that specifies courses, student section sizes, daily periods, space utilization percentages, staff planning time and lunch shifts. Other factors affecting calculations may include governmental guidelines, ventilation codes, site size, playfield quantities, locker counts and parking spaces. Middle and high schools are typically designed for 75% to 85% and 87% to 92% utilization, respectively. New learning approaches may affect these standard calculations.
Confirm that capacity calculations for your schools comply with board directives and contract commitments regarding class size. Class sizes are typically 17 to 25 for primary schools and 25 to 28 for secondary schools. As school funding and resources change, class size standards may be revised, and that can alter a building’s program capacity.
New designs for student-centered learning environments also affect capacity. For example, learning studios are supported by small group areas, breakout stations, STEAM labs, large group collaborative areas, and activity zones along circulation pathways. Every space may be occupiable with varying class sizes, potentially simultaneously, which may increase capacity.
A quick indicator of capacity is the amount of square feet per student. For example, a 1,000-student elementary school in 2025 with 135,000 square feet equals 135 sq.ft./student. This is reasonable for elementary schools with learning spaces, small and large group spaces, labs, core areas (e.g., gyms, dining), circulation and infrastructure. The typical sq.ft./student in schools has increased over time; 1970s elementary schools were designed at 70 to 80 sq.ft./student, and large comprehensive high schools were designed at about 125 sq.ft./student. Today’s high schools exceed 190 sq.ft./student.
When a school's enrollment exceeds capacity, short-term remedies may include converting general spaces for class use, installing portable classrooms, increasing class size, constructing an addition, adding off-site learning venues, and adjusting program schedules. Schedule adjustments may include split shifts, or online blended learning options.
What is the student capacity of your school? Many factors interact to bring about changes in capacity. Hire a qualified educational facility planner to guide you in finding the answer.
Paul W. Erickson, AIA/NCARB/REFP, executive officer and partner, is past president of ATSR Planners/Architects/Engineers, a firm specializing in school planning and design. Erickson has 47 years of experience in school planning, design, and construction, and can be reached at [email protected].
About the Author
Paul Erickson
Paul Erickson, AIA/NCARB/REFP, executive officer and partner, is past president of ATSR Planners/Architects/Engineers. He has 47 years of experience in school planning, design, and construction. Erickson can be reached at [email protected].