Facilities (Learning Spaces)

Weather or Not?

installing a watertight roof on a school

PHOTO COURTESY OF NICK APERGIS

Simple Things

Whether it is annual, semi-annual or monthly, most experts agree that inspections by trained personnel will reduce leaks. Richard Rast of Bluefin, LLC, in Denver, Colo., says, “One of the biggest ‘small’ things that we run into is roof leaks related to clogged roof drains, gutters and debris on the roof.” He says these inspections, done by in-house technicians or a local roofing contractor can be used to identify little problems before they become bigger problems: screws and fasteners left by HVAC maintenance personnel, open covers on roof-top mechanical equipment, a quick check of flashing systems and penetrations. “It’s simple, easy and inexpensive, but well worth the investment of time and resources. We find that this simple activity reduces roof leaks in most cases by more than 50 percent.”

Also, pay attention to how debris are disposed of. The principal at the old Sterling Elementary School in Charlotte, N.C., complained of chronic water infiltration, particularly in the fall. The school is comprised of the original building and multiple additions, forming three sides of a large courtyard that sloped toward the later additions. A visit to the school found that leaf disposal amount to raking them all to the low spot in the courtyard — the yard drain. Once the leaves were removed, proper drainage was restored.

While inspections are beneficial at any time, Len Witke, the former head of facilities for Cabarrus County Schools in North Carolina, suggests his technicians often found holes in a membrane by walking the roof a day or so after a rain. Walking on the wet insulation will often squirt water through the holes in the roof membrane.

Accessibility

Although there are times when a green roof, ballasted roof, or a roof-mounted solar system is more desirable, the common sense advice from the experts was that it is easier to find the source of a problem if the roof is visible and continuous.

When a passive solar, earth sheltered elementary school was designed and built in a western rural community 20 years ago, it was the pride of the region. When the roof began leaking recently, it was an emergency. The soil that covered the single-ply membrane and the topsoil that drifted behind the high parapet walls made repairs unfeasible. Excavation and replacement was the only option.

If a rake is used to distribute ballast, the teeth always point up. Well, maybe not always. One professional found that the rake used to distribute the ballast on his roof had put hundreds of tiny holes in the membrane. The ballast was removed, the membrane repaired, and mechanically fastened so that any other holes could be easily repaired as they were discovered.

Permanent roof access within the building complete with stairs or a ladder is an essential part of a good roof maintenance plan since regular access is critical.

Preventative Maintenance

Emergency responses are the stuff of nightmares for school facilities professionals. To counter this, Witke says, “Funding a preventative maintenance program for roofs is absolutely necessary and will substantially reduce the number of emergency responses.”

While it is still raining, there is little the maintenance technicians can do. Attempting to control the flow of water once it is in the building sometimes feels like you are rearranging the deck chairs on the Titanic. Drying everything out once the rain is over, is certainly necessary, but still not forward progress toward a solution. Substantial water intrusion disrupts classes and often mobilizes angry parents.

Slow leaks are sometimes more difficult to investigate. One of Witke’s elementary schools had a sloped roof that leaked just enough water to rust the hangers and screws of the suspended drywall ceiling. Since the water never stained the ceiling, the damage was not discovered until a 4-inch x 8-inch panel collapsed one day, narrowly missing a student.

Operating a national roof program management company, Richard Rast advises that much can be accomplished with trained in-house technicians and a proactive management of scheduled repairs. “We find that many school districts manage roofs reactively.” They only respond to emergencies when they occur, believing falsely they are saving money by doing little or nothing to achieve maximum service life if the roof isn’t leaking. Unfortunately, he says, “The results are shortened roof life, poor roof reliability and increased operating and capital costs.”

Rast believes the best opportunity to improve roof performance and reduce costs is a balanced approach of preventive maintenance and proactive management of repairs as defects are discovered. This saves in two ways: (1) Repairs done on a timely basis reduce leaks and related collateral expenses. It also prolongs serviceable life, and reduces capital expense for roof replacement. (2) If all needed repairs are identified for each building in the inventory and purchased in bulk, the unit price for each repair drops by 70 percent or more because it is more efficient for the contractor to do a larger amount of work on a schedule vs. running single repairs as a service call. He concludes, “This impacts both operating and capital budgets. Identification and documentation of needed repairs can either be done in-house or using a consultant.”

Occupant Sensitivity

roof installation

PHOTO COURTESY OF NICK APERGIS

Identifying issues is much easier during installation (whether it is builtup or single-ply) than when the roof leaks after the fact.

Often, built up roofing on schools was performed in the summer to avoid subjecting the teachers and students to the fumes. Adhesives today present similar problems to the use of hot roofing material in the past. If the roofing is done while the building is in use, occupants often complain of noxious odors. Occupied buildings may present other problems as well.

An elementary school near Annapolis, Md., had a single-ply roof being mechanically attached through the tectum roof deck during the school year. As the temperature rose during the day, the students and teachers noticed not only the odor of tar, but also black spots beginning to appear on the ceiling tiles. It seems that the built-up roof underneath the new rubber membrane was liquefied by the heat and was dripping through the holes in the deck. That summer, a fully adhered membrane was installed once a total tear-off was completed and all of the holes in the tectum were sealed.

Just as there is no substitute for a roof that is properly installed, there is no substitute for roof repairs that are timely and appropriate. Much of leak prevention is common sense: knowing the material and its’ idiosyncrasies, knowing how it performs in your local weather conditions, inspecting regularly relying on documentation and not institutional memory to clear debris, and looking for possible problems, not waiting for them to occur.

There is no perfect roof. As Clayton Dekle said, it’s about WHEN, not IF it will fail.

This article originally appeared in the issue of .

About the Authors

Mike Raible is founder and CEO of The School Solutions Group in Charlotte, N.C., and the author of "Every Child, Every Day: Achieving Zero Dropouts Through Performance-Based Education". He can be reached at [email protected].

Andrew LaRowe is president of EduCon Educational Consulting located in Winston Salem, N.C. He can be reached at [email protected]