Green Schools—A Multiple Choice Questionnaire
Green schools, what a no brainer! Of any buildings (other than hospitals), where does it make more sense to have a focus on daylighting, high indoor air quality, connection to exteriors and, of course, high-efficiency systems than in schools — the places where we educate the future of our nation? LEED for Schools has been rolled out in the past few years and has seen a good adoption rate at the K-12 levels. I’ve had the opportunity to work on three of these schools, so I’m going to pass on a few impressions.
As compared to other LEED rating systems, you won’t find any surprises. The same prerequisites are there, with the addition of two more (which I’ll get to shortly). Combine those with the five new school-specific credits (including master planning facilities, offering joint uses of buildings, increasing acoustic performance and proactively preventing mold), and you’ve got yourself a LEED for Schools program.
First, the prerequisites: one is pretty basic, but I’ve seen pretty substantial cost premiums with the second. Under Sustainable Sites, the prerequisite that a project must do a Phase 1 Environmental Site Assessment has been added. And, if there are any findings, a remediation must be performed. In the private sector world, this is pretty much standard anytime you purchase a property. I guess I don’t have enough familiarity with how it works in the schools world, but if USGBC had to specifically add it as a prereq, I’m a little scared to learn what’s been going on in the past!
Minimum Acoustical Performance
The second new requirement is under Indoor Environmental Quality. Minimum Acoustical Performance is a requirement designed to improve the learning environments where our kids spend eight hours per day. The credit basically dictates a minimum noise reduction coefficient (NRC) for 100 percent of ceiling areas of 0.70 or higher and a maximum background HVAC noise level of no more than 45 dBA in all core learning spaces. Creating a better learning environment is definitely a positive, and eliminating background noises, etc., certainly helps students. However, this prerequisite is one I’ve seen some teams have issues with.
First, the NRC for ceiling tiles. Two of the projects I worked on began design as traditional, non-LEED schools well before I was involved. The specified ceiling tiles had an NRC of about 0.50. The change in tile to LEED compliant tile cost about $0.50 extra per square foot, which isn’t chump change for these projects.
The second requirement for maintaining less than 45 dBA required a significant rework of the HVAC systems in the rooms. No dollar value I can quote, but it was a substantial effort to rework the system and earn compliance. Now, of course, on the third project (same team) it was LEED from the get-go, so the systems were designed properly, which again reiterates the best, most cost-effective way to earn LEED is to start from day one! That said, the team did express concern that some HVAC systems typical in their school districts (such as through-wall units) would be too loud no matter what and would eliminate the building from LEED consideration. I’m certainly no acoustical expert, so I can’t verify if this is the case; but it was a cause for concern.
A Question of Maintenance
This leads me to the second question for green schools. Now that they are built efficiently and effectively, how are they actually maintained? In my conversations with design teams and school districts, I heard a lot of the same thing — they did not want to install higher-efficiency HVAC systems because they had no one qualified to maintain them. The districts simply didn’t have facilities people who could maintain cooling towers, much less chillers, properly. In a very local case, a large HVAC efficiency study was performed by Trane, and the results showed the VAV/cooling tower buildings in the system operating much less efficiently than the standard, through-wall systems! The high-efficiency systems started off great, but they fell into disrepair and inefficiency through improper settings and maintenance due to a lack of understanding of proper operations. The through-wall systems were easily understood and easy to replace if something failed. This isn’t what we had hoped to hear.
I could go on and on, but this simple case study epitomizes the main challenge I see facing the ongoing success of green schools. Hopefully, it is confined to just the districts I’ve seen and isn’t wider spread. But I doubt it. Careful consideration must be taken when designing and building our new green schools (including bringing the O&M folks into the design process) to ensure the long-term success of both the buildings and the students in them for the green schools movement to be considered successful.