What's a School's 'Functional Capacity?'

Cynthia Owens Richardson, director of Planning for the Chesterfield County Public Schools, in Virginia, asks a lot of questions, looks for new information wherever she can find it and is not satisfied with easy answers or standard results. She wants more.
Dr. Richardson raised the question about small schools that triggered my column on that subject (SP&M, April 2012). Now she has raised a more complicated question: How does one measure the functional capacity of a school? She mentions a standard benchmark (when 90 percent of the space is occupied, the school is full), but she and dozens of persons who have responded to her, have questioned where that benchmark comes from and how adequate or accurate it is.
I worry about any attempts to set standards on something like that. It seems to me that any response should emphasize how a space is used and supported, rather than specific numbers of students or percentage of occupancy.
My firm specifies elementary school classrooms of at least 900 square feet no matter how many students are going to be in a class because we believe that is the minimum space needed to allow a variety of elementary school activities to occur. How do you calculate capacity for a school when a room is “full” with 22 students or 28 or even 15?
Another factor that needs to be considered in calculating capacity is support facilities. Schools are not just classrooms. I visited an elementary school in Louisiana that was designed to house 500 students. As the school population grew, the district added four classrooms, then eight more and then another eight. As a result, the school was operating with 1,000 students. It was functioning but, in my opinion, it was way above functional capacity.
One thousand students were using a cafeteria, a library and a multipurpose room designed to accommodate 500 students. Worse, the toilet facilities were designed for 500, too. There were long lines of students waiting to reach them before each lunch period. So, there were classrooms able to hold 1,000 students, and the building was rated for 1,000, but the real key to functional capacity was the availability of support facilities, and they were designed for 500.
High schools and elementary schools, as they are generally operated, function in a similar manner. In an elementary school, a teacher and a group of students “own” a classroom. When they leave for lunch, music or any similar activity, the room is empty.  If the day is divided into eight periods and students leave the room twice a day (say for lunch and an activity), then the classroom is used 75 percent of the time (six periods out of eight).  Is 75-percent occupancy full capacity?
Similarly, in a high school, ideally a teacher is assigned to a room, and when the teacher does not have a class or an assignment, the room should be empty. If the school runs on an eight-period day and the teacher has five classes and a duty period, then the room is used 75 percent of the time.
Unfortunately, in many high schools, teachers do not have a room of their own and must allow the classroom to be used at least one period each day by another teacher. To cover this situation, we use a benchmark that suggests that a classroom should be empty one period a day (for flexibility), that special rooms that need setups (think science labs, art studios, etc.) should be scheduled 50 percent of the time (one setup for each class use) and that physical education space could be scheduled every period, with different faculty overseeing it. It is not perfect (and it does not provide a classroom for each teacher), but it does take into consideration how each space functions.
Middle schools are another matter entirely. Ideally, a group of students and their teachers should have a block of rooms that are their home. When they leave, those rooms should be empty so that projects can be left or individual students and teachers can use them for whatever they need to do. That suggests that in a middle school that really uses teams and houses and provides them with space for their activities, classrooms are “full” when they are occupied 50 to 60 percent of the day.
That 90-percent rule of thumb? It’s a nice formula, but it is just that, a model, not a reflection of the actual activity of the school. Usage and educational philosophy, not some mathematical formula, should determine how space is used and what percentage of use equals capacity.

Paul Abramson is education industry analyst for SP&M and president of Stanton Leggett & Associates, an educational facilities consulting firm based in Mamaroneck, N.Y. He was named CEFPI's 2008 "Planner of the Year." He can be reached at [email protected].

About the Author

Paul Abramson is education industry analyst for SP&M and president of Stanton Leggett & Associates, an educational facilities consulting firm based in Mamaroneck, N.Y. He was named CEPFI’s 2008 "Planner of the Year."