When the roof on Bishop Elementary School outlived its warranty, the Lincoln Consolidated School District put the roof replacement project up for bid. The school district already had a specific product in mind, and that made things pretty straightforward for Superior Services RSH Inc., headquartered in Lansing, Michigan.
Founded in 1975, Superior Services focuses on commercial and industrial low-slope roofing. The company also has an architectural metals division and a dedicated service and maintenance department. According to Derek Heins, its vice president, the company works closely with Duro-Last Roofing, and that relationship was key to being awarded the bid to re-roof Bishop Elementary School in Ypsilanti, Michigan.
“The existing roof that was on this building was a Duro-Last roof. It had been on there for more than 20 years, and the school had been very happy with its performance,” Heins says. “Most of the other buildings in the Lincoln Consolidated School District have Duro-Last roofs, so they are really comfortable and really familiar with the product. The school likes the single-ply PVC and the reflectivity of the white membrane, and have been really happy with the performance.”
During the bidding stage, Heins suggested a way the project could save money while putting less stress on the environment. “We suggested utilizing the Recycle Your Roof program with Duro-Last Roofing,” he says. Through the program, mechanically attached Duro-Last PVC membrane can be returned to the manufacturer at the end of its useful life.
Heins explained the benefits of the recycling program to the district, which included a lower installation cost. “You’re reducing landfill costs by not bringing in dumpsters and paying for disposal of the old membrane,” he notes. “We essentially take it directly to Duro-Last’s factory, where they grind up the material and use if for making products including flooring and rooftop walkway pads.”
The school district agreed, and more than 8,700 pounds of the existing PVC roofing membrane was recycled as part of the re-roofing project.
Removal and Replacement
The 77,000-square foot roof featured different elevations. The center area where the two wings met was divided into several sections, most separated by parapet walls. The roof also features a large skylight, which was replaced as part of the project. The site-specific safety plan incorporated for each section included a perimeter warning line system and personal fall arrest systems (PFAS). A guardrail system was set up around the skylight.
The first step was the tear-off. The roof removal process is critical for the recycling program. “When we started the project, we sliced the roof membrane at the fastening rows,” explains Heins. “By doing this, it allowed us to roll up the loose membrane between the fastening rows. The rows were approximately 5 feet wide. After rolling them up, we tack welded the rolled-up material using a hot-air welder.”
The rolls were removed from the roof with the assistance of a telehandler, stacked on pallets, and secured with straps. Crews then removed the fastening tabs and fasteners from the existing roof system, using screw guns to back out the fasteners from the metal deck.
The next step was inspecting the underlying polyiso insulation for any moisture, damage or deterioration. It was replaced as necessary, but the vast majority of it was reused, which offered additional cost savings.
New tapered drain sets were installed for all of the internal drains on the building. “We used the Duro-Guard insulation tapered drain sets,” Heins notes. “We cut out the existing insulation and put in new wider drain sets to help promote water flow on the roof.”
The tapered drain sets are prefabricated and pre-sloped. They are available in two sizes: 4 feet by 4 feet, and 8 feet by 8 feet. “We try to use larger size drain sets whenever possible,” Heins says. “They unfold to form an 8-foot box around the drain. The marked center circles allow you to simply lay it over the drain sump and cut out the sump opening.”
Crews then installed the 50-mil Duro-Tuff PVC roof system, which was mechanically attached. Enhancements at the perimeter were made using a RhinoBond induction welder.
“We install a hybrid perimeter using RhinoBond induction welding,” Heins explains. “We run two wind rows around the perimeter of the building. Then we roll out the 10-foot wide membrane rolls. With the membrane rolled out, we fasten it down per the manufacturer’s specifications. After we finish putting the membrane down, we go back and use the RhinoBond machine to weld the membrane down to all the perimeter plates for our wind laps.”
Crews then installed prefabricated accessories, including custom-manufactured wall flashings, curb flashings, and stack flashings. Drains were fitted with new drain inserts and strainers. Crews also installed a new Bilco S-20 roof hatch.
Perimeter metal and copings were supplied by Exceptional Metals. “We used their two-piece compression metal,” Heins notes. “We also installed custom scupper collector boxes and downspouts on the project as well. By using Exceptional Metals, a division of Duro-Last, we were able to include everything in their Edge to Edge Warranty.”
Heins points to the large skylight as one of the most difficult details on the project. The existing skylight was replaced with a new custom-made Velux double dome skylight, which was installed after the roofing work was completed. When the new skylight arrived at the site, crew members lifted it to the roof and removed the existing skylight. The temporary flashings were replaced with new flashings as the new skylight was installed.
The biggest challenge on the job was the tight schedule. The project was completed in two weeks during July of 2019. “We had a limited window of time to complete this project,” says Heins. “Like most school construction projects, we were required to complete the roof during the summer break, making it essential to finish as much work as possible each day.”
At the end of the project, the old membrane was put on a trailer and returned for recycling.
Heins is proud to promote the Recycle Your Roof program as a win-win proposition. “It’s best for everybody to be conscious of the environment,” he says. “We focus on being environmentally friendly, and we also focus on the cost savings. Recycling the membrane and reusing the insulation that is in in good condition offers a big cost reduction for our customers — and it keeps the material out of the landfill.”
According to Heins, this project highlights some of the strengths of Superior Services. “One of the things this project demonstrates is our commitment to utilizing the latest roofing technologies,” he says. “One example is Duro-Last’s prefabricated accessories. Duro-Last has always been a frontrunner in providing prefabricated and custom accessories, and Exceptional Metals offers further custom fabrication. It is important to us, as a company, to strive to be on the leading edge of technology, both on the roof and in the office. It’s part of our culture, as well as emphasizing sustainability and energy-efficient roofing.”
Roofing Contractor: Superior Services RSH, Inc., Lansing, Michigan, https://superiorservicesrsh.com
Roofing Membrane: 50-mil Duro-Tuff PVC, Duro-Last, www.duro-last.com
Edge Metal: Exceptional Metals, www.exceptionalmetals.com
Roof Hatch: S-20 Type S Roof Hatch, BILCO, www.bilco.com
Skylight: Custom-Size Double Dome Acrylic Skylight, Velux, www.veluxusa.com