Located in eastern Washington, Cle Elum-Roslyn School District is nestled along the foothills of the Cascade Mountain range. With four schools, the district encompasses roughly 600 square miles of Upper Kittitas County and serves nearly 900 students from kindergarten through 12th grade.

During the winter months, facilities managers began experiencing small leaks. Unfortunately, the school district didn’t have sufficient funds to replace the entire roof system due to budget constraints. To help offset costs, the roofing consultant recommended surveying the existing roofs to put together a plan to manage the schools’ roofing assets.

They also needed a resilient roof that could weather the extreme temperature differentials; summers are much hotter and winters cooler than the state’s western half. In addition, they wanted it to complement the patina green metal systems currently in place.

The rocked BUR was the original roof from when the building was constructed in 1992. Before construction could begin, our DERBIGUM Approved Contractor (DAC) thoroughly inspected the roof to evaluate the condition of the existing BUR system. Core samples and an infrared scan found that only 3% of the roof had damaged or wet insulation.

After removing damaged material and necessary repairs made, a 1/2” gypsum coverboard was mechanically fastened through the original roof to provide a smooth working surface while also providing an additional layer of fire protection. A three-ply system, consisting of Derbibase Ultra, Derbigum GP, capped with Derbicolor GP-FR, was installed for worry-free performance. Our Derbicolor slate cap sheet perfectly complemented the patina green metal edging already in place.

The biggest challenge on this project was this roof was an open-edged 2:12 sloped deck with very few wall areas. Therefore, each DERBIGUM ply was roofed in a strapped fashion, parallel with the slope. With most of the roof visible from ground level, aesthetics were just as important as the system’s performance.

Special care was taken by our DAC, ensuring that each successive ply was straight and properly staggered. Such precise attention to detail is easily noticeable by the symmetrical lap lines of the perfectly heat-welded Derbicolor cap sheet. With almost 460 mils of redundant waterproofing performance, Cle Elum-Roslyn students will have secure, distraction-free classrooms for years
to come.