The New School Design Imperative
- By Michael Fickes
- 10/01/06
As the nation’s school districts battle deferred maintenance costs — with overall estimates ranging from $112 to $322 billion — something really bad has happened: The cost of energy, for which payments cannot be deferred, has skyrocketed.
Rising energy costs may do what billions in deferred maintenance could never do: force school renovation and construction budgeting based on life-cycle costs that include maintenance and utilities, instead of just first costs for construction.
That is exactly what has happened in New Haven, CT. In 1995, New Haven Mayor John DeStefano, Jr. launched the Citywide School Construction Program to renovate or replace all 50 of New Haven’s K-12 schools.
About four years into the construction program, a progress report indicated that the increased square footage in the new buildings would raise total maintenance and utility costs beyond the city’s ability to pay.“They were building all these nice new schools, but wouldn’t have the budget to operate them,” says Tom Rog’er, program director of the school construction program with Gilbane Building Company, Inc.“As a necessity, we had to begin looking at the efficiency of these buildings and to make sure that what was built would be the most efficient possible and that maintenance and energy costs would be affordable.”
Modeling Affordable Schools
Gilbane adopted a design tool called DOE-2 that was developed by James J. Hirsch & Associates of Camarillo, CA, and the Lawrence Berkeley National Laboratory in Berkeley. It is a free software application that enables architects and engineers to model, evaluate, and refine energy and maintenance costs created by various design decisions.
Suppose a design budget calls for $40 per sq. ft. for heating, ventilating, and air conditioning (HVAC) costs, the average HVAC cost for school buildings in New England, according to Rog’er. At the same time, suppose the master plan calls for a building that is efficient to operate.
An engineer might search out the most efficient chiller, boiler, and building system controls to satisfy this assignment. But such a system might easily cost out to $50 per sq. ft., $10 more than the budget allows.
“With DOE-2, we can check costs and factor in paybacks,” Rog’er says. “Sometimes the payback for using more efficient systems can reduce the cost per square foot. Sometimes it can’t.”
In one case Rog’er recalls budgeting $4 per sq. ft. for the cost of building system controls. Among those controls were 2,000 CO2 occupancy sensors that cost $50,000. According to DOE-2, however, those sensors would save only $35,000 through the life of the building. “We got rid of them,” he says. “They didn’t pay for themselves.”
Things don’t always turn out as common sense suggests. For example, a chiller with a 50 percent efficiency rating will always perform less efficiently than a chiller rated 60 percent. But that doesn’t mean the more efficient chiller is right for a particular building. “You have to check components in the context of the building’s life cycle costs,” says Jay Brotman, a partner with Svigals + Partners Architects, a New Haven architectural firm deeply involved in the Citywide School Construction Program. “In one case, DOE-2 might show that the extra 10 percent of efficiency requires a payback time longer than is worthwhile. Or a particular model may have maintenance issues that raise its cost.”
For example, notes Brotman, schools in New England don’t use water-based cooling towers because they run up labor costs in the winter, when the towers must be drained.
In another school, the DOE-2 model helped specify instant hot water heaters instead of the usual central system. “This pre-K to 8 school has two major uses for water: showers in the gym and water for the kitchen,” Brotman says. “Since these are young kids, the showers in the gym aren’t used often, so it would have been expensive to store hot water for that. Likewise, the kitchen is only used part of the day. The DOE-2 model indicated that instant hot water heaters were all that would be necessary.”
What’s A Model Worth?
The use of the modeling program has already begun to pay off. According to Rog’er, when the program started, the designers and the building operators — Philadelphia-based Aramark Corporation — aimed to drive down average building operating efficiency in the school system. At that time, the 50-building system used an average of 250 KBTUs per year per building.
“That’s off the charts in terms of poor efficiency,” Rog’er says. “We were in the least efficient one percent of all the buildings in New England.”
Within one year, building operating efficiency — which then focused largely on day-to-day building operations managed by Aramark — had fallen to 160 KBTUs and moved the district up into the 20th percentile of all New England school buildings.
The second year of the DOE-2 program, which ended in December of 2005, saw average efficiency fall to 110 KBTUs per building, pushed the school system into the 65th percentile. “We did this in two years with very little new construction,” says Rog’er. “The new buildings that we’ve designed are being measured in the range of 55 to 70 KBTUs. By the time we’re finished, we hope to have the district average down to 80 KBTUs.”
According to Rog’er, 1 KBTU per sq. ft. per year represents $60,000 in utility costs across the New Haven school district. By reducing KBTU use from its current average level of 110 to 80, incorporating the DOE-2 modeling program into the design process will have generated savings of 30 KBTUs or $1.8 million per year.
What happens to that money? Is it put aside to pay for maintenance, thus avoiding the problem of deferred maintenance costs plaguing current schools?
“Tricky question,” Rog’er says. “These are all avoided costs. You should take some of the avoided costs and pay for a higher level of maintenance so that you don’t fall back into the kind of jam you were in before. But that will take a real commitment from the school district.”