OXFORD — School officials say the roofs of the district’s 10 school buildings are safe despite 18- to 24-inch piles of snow on many of the roofs.

Portions of several roofs, such as the Oxford Hills Comprehensive High School, the Oxford Hills Elementary School annex and Rowe Elementary School, did have drifting snow piles that were as high as 72 inches removed, Facilities Director David Marshall said on Friday.

“We went up on every roof and measured the snow with a yardstick,” Marshall said. The measurements were then brought to the attention of Superintendent Rick Colpitts and Business Manger Cathy Fanjoy to decide the next step.

Because the 72 inches of snow was more than considered structurally sound by engineers, the decision was made to hire an outside contractor to shovel the snow off the roof.

Eighteen to 24 inches of snow is considered OK, Marshall said.

Late last week, Education Commissioner Angela Faherty issued a warning to school officials about mounting concern over the state’s school buildings’ ability to sustain the heavy snow load being created by multiple snowstorms this year.

She asked that superintendents give the “highest priority” to ensure that there were no structural failures on school roofs.

“We’re really in good shape,” Marshall said after the snow piles had been removed.

The snow weight all depends on whether it is wet or dry and when the school was built in terms of when the roof load becomes too heavy, Marshall said. Four feet of dry, powdered snow is much different than two feet of heavy, wet snow, he said.

“It’s like a bucket of water and a bucket of fluff. There’s a huge difference,” he said.

Although most of the schools have flat roofs or have areas of their roofs which are flat, Marshall said that is not necessarily a hindrance to the safety of the roofs when snow piles up.

In fact, he said, flat roofs can be a plus because snow loads generally do not fall off the roofs and pile up in front of windows or cause erosion when rain pours off them. The flat roofs are designed with interior drains that allow the water to drain inside a system rather than off the side of the building.

Flat roofs are also generally used in school building construction because they are substantially cheaper to build because pitched roofs on large building are not cost effective.

Marshall said that structural engineers determine how much snow load a particular roof can take in its design. But, he said, when a roof is updated, such as was the case when a portion of the 1975 middle school roof had to be brought up to today’s code, the snow load capacity may change also.

Only a few leaks have been detected — at the high school and Rowe Elementary School — because of ice dams built up under the snow loads, Marshall said.

ldixon@sunjournal.com

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