Award-Winning Re-Roofing Project Showcases Quality Workmanship

Photo: Duro-Last

Replacing the roof on an occupied building with multiple tenants means not only meeting the needs of the building owner but several other businesses as well. When the roof is high above a busy metro area, the job can be even more demanding, but when the failing roof on a CBRE Group high-rise in Cambridge, Massachusetts, needed to be replaced, Commonwealth Building Systems was up to the challenge.

Located near the Longfellow bridge across the Charles River from downtown Boston, the building houses a variety of business and retail tenants. RMX Northeast Inc., the consultant on the project, specified the use of a PVC roofing system from Duro-Last to replace the existing stone-ballasted system and invited local contractors to bid on the project. Commonwealth Building Systems of Rockland, Massachusetts was awarded the job.

Photo: Duro-Last

Commonwealth is a commercial roofing and sheet metal contractor that focuses on the Boston and Cambridge area. Daniel Hulverson, principal at Commonwealth Building Systems, knew the logistics on the project would be a challenge. Due to construction taking place on the Longfellow Bridge at the time of the project, traffic in the area was diverted around the building, and use of a crane was limited to Saturdays. The Commonwealth team commissioned the use of a 300-ton crane on two consecutive weekends to remove the stone ballast, pavers, and existing EPDM membrane from the 180-foot-tall, multi-level roof.

“The ballast removal was probably the hardest part of the project,” Hulverson recalls. “We couldn’t do any work doing the week because of the tenants for one, because of the noise, and the Longfellow Bridge was under construction at the time. It was actually closed, so traffic was pretty much a nightmare.”

R.K. Hydrovac was called in to remove the stone ballast. The crane was used to hoist the vacuum hoses to the roof. “It was quite an undertaking on their end,” Hulverson says. “We got the stone ballast off and got all of the stock up there on two consecutive weekends. Actually, after the first weekend we were able to get started roofing. We stockpiled all of the trash and got most of the trash off on the second weekend. We had a couple more crane days to get trash out at the end, so we had maybe four of five crane setups in all.”

A Custom Solution

The new roofing system was designed to stand up to the area’s high winds. Leaving the existing insulation in place, the Commonwealth crew covered each roof area with 2 additional inches of Duro-Guard ISO II insulation, which was mechanically attached. The upper roof was above a steel deck, and the lower roof covered a concrete deck, so different fasters were used, but the fastening patterns were identical.

After the existing ballasted EPDM system was removed, crews installed a thermoplastic roof system manufactured by Duro-Last. Photo: Duro-Last

After the insulation was in place, the Duro-Last PVC membrane was attached using the Duro-Bond induction welding system. The membrane is delivered custom fabricated to fit the site. “Duro-Last comes out and pre-measures the job with our assistance, and then the sheets are made,” Hulverson says. “They give you a map and tell you where the sheets go. They measure around all of the penetrations, and everything is pre-cut. It’s pretty cool how it comes out. The rolls are listed A, B, C, D, and so on, and you just kick out the rolls and weld them in place. The sheets are pre-welded at any laps, so it reduces the amount of welding you are doing on the job and saves time.”

The Duro-Bond system uses specially coated plates that are screwed down to the deck before the membrane is put in place. The membrane is adhered to the plates using an induction welder.

Work began on the upper level and moved down to the lower level. “We went from side to side, working our way toward where the crane setup was going to be,” Hulverson explains

The upper roof was constructed over a mechanical room, so crews could work any time without fear of disrupting the tenants. Work hours were restricted on the lower level because it covered occupied business space. “We had to switch to very early hours in the morning because of the noise,” Hulverson notes. “We were starting at three in the morning so we didn’t disrupt the tenants.”

Commonwealth’s dedication to quality workmanship on the project earned the company Duro-Last’s Edge-to-Edge & Deck-to-Sky Award. Photo: Duro-Last

Staging areas were moved as the project progressed to limit the possibility of damage to the completed sections of the roof. On the last day, the roof membrane was protected by tarps and plywood as the final loads of debris were removed.

The safety concerns were straightforward. “There was a parapet wall that was above 42 inches high around the whole perimeter of the building, so safety-wise, this job was fairly easy for us,” Hulverson says.

Custom-fabricated curbs and stacks were utilized to help reduce rooftop labor. “All of Duro-Last’s curbs and pipe seals come pre-made, and they are all listed on that diagram,” Hulverson says. “You just unfold them and weld them. The corners are already pre-done. It’s a very nice system.”

Commonwealth’s sheet metal division installed all of the edge metal, which was custom fabricated by EXCEPTIONAL Metals. “Again, Duro-Last measures everything along with our superintendent, and it’s all sent out prefabrication,” Hulverson says. “The pre-assembled wall cap was installed on top of the walls.”

During the last phase of the project, Walkway pads were welded down in high-traffic areas.

Luckily, weather wasn’t a key factor. “There were some challenging windy days, as there always are in Boston, but nothing I can really remember that slowed us down to the point we couldn’t work,” says Hulverson. “The weekend crane setups and the size of the crane were unusual, but other than that it was a pretty smooth job. And the views are beautiful — you’re looking across the Charles River into Boston, so it was pretty nice.”

Commonwealth’s dedication attention to detail on this project earned the company Duro-Last’s 2018 Edge-to-Edge & Deck-to-Sky Award, which was presented in 2019. “Duro-Last was impressed by the neatness of the job, especially the wall flashing,” Hulverson says. “They were impressed with our workmanship. If there were any challenges or changes, we just met them head on and moved forward, like we typically do. The customer is always first.”

Hulverson believes the key to ensuring quality workmanship is dedicated employees, from top to bottom. “Our foremen are well trained, as are our superintendents, and I actually look over the jobs in the field as one of four owners,” he says. “We make sure the quality and craftsmanship are done the right way.”

TEAM

Roof Consultant: RMX Northeast Inc., Milford, Massachusetts, www.rmxne.com

Roofing Contractor: Commonwealth Building Systems, Rockland, Massachusetts, www.commonwealthbuildingsystems.com

MATERIALS

PVC Membrane: Duro-Last, www.duro-last.com

Insulation: Duro-Guard ISO II, Duro-Last

Edge Metal: EXCEPTIONAL Metals, www.exceptionalmetals.com

During Hospital Expansion, Contractor Protects Patients – and the Environment

The recent expansion of Pella Regional Health Center included adding a new third floor to the hospital. Photos The Duerson Corporation.

It’s not often a roofing contractor installs a new roof on a building before removing the old one, but that was just one of the wrinkles encountered by The Duerson Corporation during the recent expansion of Pella Regional Health Center in Pella, Iowa. The project involved adding a new third floor to the existing two-story hospital without disrupting the care of the patients below.

Protecting patients and meeting the needs of the hospital were the top priorities on the project, but another key focus was sustainability. Thanks to the initiative of The Duerson Corporation and Duro-Last, the roof system manufacturer on the project, almost all of the components on the existing roof were recycled, including the membrane, insulation, screws and plates.

The Game Plan

Based in Altoona, Iowa, The Duerson Corporation has been in business since 1986, specializing in commercial and industrial roofing, both new construction and retrofit. Kirk Duer, the company’s president, and Tanner Duer, head of business development, shared their insights on the Pella Regional Health Center Project with Roofing.

The Duro-Last roofing system included a vapor barrier, polyiso insulation, a cover board, and 50-mil white PVC membrane. Details included custom-fabricated curb flashings, walkway pads, and edge metal. Photos The Duerson Corporation.

They note that the goal on every project is to meet the client’s needs. “The hospital is a good example of that,” Kirk notes. “We took care of some maintenance and leak issues in the beginning, and then as time went on and trust was established, we did some re-roofing projects for them. Then they did this addition. It all flowed very well together.”

In a nutshell, the expansion plan involved erecting the steel for the new third floor, adding the roof deck, and installing the new roof system. The existing roof was left in place during this phase of construction, as the hospital was still active. After the walls were completed, the old roof system could be removed and recycled, and finally the interior work could be completed.

The first step involved erecting the steel for the new third floor. Kirk credits the hospital administrators for detailed planning before the project even got underway. That was the reason the existing roof was home to multiple 2-foot-by-2-foot boxes, complete with curbs and flashing.

Kirk Duer (left) and Tanner Duer of The Duerson Corporation in Altoona, Iowa, made sustainability a key focus of their business after they started recycling PVC membrane as part of Duro-Last’s Roof Take Back Program. Photos The Duerson Corporation.

“Those boxes covered the steel from the I-beams that were coming out of the roof, ready to receive that third floor,” Kirk notes. “When those boxes were removed, they just took their new steel and went up. It’s one of the more unique things I’ve ever seen in my history in the industry.”

As the steel went up, flashing the newly exposed I-beams was the first phase of the roofing work. “In the very beginning, once the general contractor removed those boxes, we added membrane and insulation around the I-beams and made sure they were watertight while the steelworkers erected their steel,” Kirk notes. “It was critical to keep it watertight because they still had patients right beneath us.”

Installing the New Roof

The new roof system covered an area of 27,600 square feet, bordered on one side by a long, curved parapet. The roof was installed over a structurally sloped steel deck with internal drains. “The first thing we did was install a vapor barrier over the entire deck,” Tanner notes.

The system consisted of Duro-Guard polyiso insulation with an R-value of 30, DensDeck cover board, and 50-mil Duro-Last white PVC membrane. Details included custom-fabricated curb flashings, Roof Trak III walkway pads, and coping and edge metal from Exceptional Metals.

Hospital administrators wanted a warranty from one source, notes Kirk. “Duro-Last refers to it as edge to edge, deck to sky,” he says. “Every component is supplied by Duro-Last and warranted by them for a full-system warranty. This particular administrator is adamant that this is what he wanted, and that’s what we delivered for them.”

Weather was not an issue, but the crews had to be ready to move quickly in the event of emergencies. “Work took place in September and October, which is about the most beautiful time of the year for us,” says Tanner. “The only unusual thing was that we had to have walkie-talkies on us at all times so they could alert us whenever a helicopter was coming in. Plant ops would notify us when a helicopter was coming in, and basically anything we had in the air we had to move down to the ground. We obviously wanted to make sure Pella Regional was not going to have a problem with us when a patient was flying in.”

After the metal roof deck was in place, crews installed a vapor barrier. Photos The Duerson Corporation.

The roofing installation was pretty straightforward, notes Kirk. There was one area on the lower roof that was an exception, as the new construction blocked access to the drains. “Originally the roof sloped in one direction, but because of the design of the new part of the building, we had to change the slope,” he says. “We had to turn everything around so water would flow in the other direction.”

On this section, the existing roof was torn off and removed, and tapered insulation was used to provide the proper slope. It was installed on a concrete deck over a working section of the hospital, so the installation was a bit tricky. “Rather than starting at the drain, which would be the easiest thing to do, we had to start at the furthest point away,” Kirk notes. “We were adding so much insulation, we didn’t want to create a bathtub, if you will. We had to start at the high point and work our way downhill so when we got to the drain, we’d have the correct elevation.”

Recycling the Old One

Once the third floor was closed in for the winter, it was time to remove the existing roof. “That was the fun part,” Tanner says.

The old roof was removed through a window. “We had an opening that was approximately 5 feet wide and 4 feet

The new roof system covers 27,600 square feet of the new third floor in an area bordered on one side by a long, curved parapet. Photos The Duerson Corporation.

tall,” Tanner recalls. “We took a fork lift with a BOXhaul on it and basically went up to the outside of the window and stuck it in there as far as we could without damaging any of the structure and started removing the material.”

No gas-powered vehicles were allowed to operate in the interior space. The fasteners had to be unscrewed and separated by hand. “When we removed the material, we tried to cut along the seams so we could see the screws and plates,” notes Tanner. “We sorted those out, and in the end we had more than 1,000 pounds of screws and plates we took back to our shop to be recycled.”

The existing membrane was cut up into 5-foot strips. Sections were rolled up and bundled for removal using a portable bander. Once the BOXhaul was full, it was taken to a flatbed trailer. “We completely filled the 20-foot trailer with old material to be recycled,” Tanner says. “In the end, there was 7,200 pounds of Duro-Last membrane that we recycled.”

The membrane was recycled as part of Duro-Last’s Roof Take Back Program. The company recycles the membrane, using it to construct products including walkway pads. “We’re lucky enough to have a Duro-Last plant in our state, and I actually took that load of material to be recycled to Sigourney one day,” Tanner says. “When I got there, they took a fork lift out there and unloaded it for me.”

The expanded polystyrene insulation was also removed and recycled. It was taken to Insulfoam, the original manufacturer. “The insulation necessitated a few more trips because it was so bulky,” Tanner says. “We kept an empty tractor trailer on site. In the end, we filled up three of those with approximately 120,000 board-feet of insulation that we took off of that project.”

The membrane that once covered the existing roof was cut into strips and rolled up for transport to the plant for recycling. Photos The Duerson Corporation.

The Duerson Corporation recycles as much material as it can throughout the year, including scrap metal and PVC membrane, which is stored in Duro-Last approved containers until there is enough to be transported to the plant.

“I thank Katie Chapman at Duro-Last for getting this program up and running and making us aware of it,” says Kirk. “Otherwise, that material would’ve just ended up in a landfill.”

Participating in the membrane recycling program was an eye-opener for everyone at the company. “One thing leads to another,” Kirk says. “We started recycling the roof membrane, and then you realize that there are other things you should think about. What do we do with the insulation? What do we do with the screws and plates? We started looking for ways to recycle everything, and pretty soon a full-blown sustainability program is born. It really does change the way you think once you buy into the system.”

The New Floor of the Hospital

After the general contractor removed the old vapor barrier with a floor scraper, the new third floor section was converted into a brand-new, pristine Obstetrics and Gynecology unit. The difference between the construction site and state-of-the-art hospital wing is striking.

The third floor of the hospital now houses a brand-new Obstetrics and Gynecology unit. Photos The Duerson Corporation.

“What we knew as the concrete roof deck was also designed to serve as the finished floor of the hospital,” Kirk says. “The new O.B. unit is just beautiful. If you look at that you can’t even imagine, unless you’ve been through the whole process, that the area with carpet and tile you’re looking at months ago used to be the roof.”

Safety for the roofing crews is always a priority at The Duerson Corporation, but safety precautions on this project also included ensuring the safety and security of the people in the hospital. “It was critical that we were always aware of the patients underneath us,” Kirk notes. “We had to be very mindful about the positioning of our generators, for example, so the exhaust wouldn’t be sucked into the fresh air intakes.”

Tanner points out that a checklist is prepared for each project to make sure everyone is aware of the client’s needs. This is especially important in health care projects like this one. “If someone goes out to take care of a leak call, for instance, we make sure they know everything they need to know to keep the client happy,” Tanner says. “With a health center, you have to take extra precautions. This can include items like making sure when you’re walking across the open roof that you don’t look into a patient’s room.”

“We’ve learned a great deal from working with Pella Regional Health Center in terms of just how mindful of everything we need to be,” Kirk says. “We recognize each of our clients, even though they all have a roof over their head, they all do something different for a living. In reality, everybody in any trade needs to recognize what your client does and what you need to do to be mindful of that.”

It takes communication to understand clients’ needs and build long-term relationships with customers. “We’ve got clients that we’ve serviced for 26 years,” Kirk says. “We’re all here to serve other people. In our case, it’s in roofing. Whether it’s a hospital or a convenience store, we’re serving them, and it all starts with that relationship.”

TEAM

Architect: Shive Hattery Architecture & Engineering, West Des Moines, Iowa, www.shive-hattery.com
General Contractor: Graham Construction, Des Moines, Iowa, www.grahamconstruction.com
Roofing Contractor: The Duerson Corporation, Altoona, Iowa, www.duersoncorporation.com

MATERIALS

Membrane: 50-mil Duro-Last white PVC membrane, Duro-Last, www.durolast.com
Insulation: Duro-Guard Polyiso, Duro-Last
Vapor Barrier: Duro-Last Vapor Barrier, Duro-Last
Coping: Coping and 2-piece edge metal, EXCEPTIONAL Metals, www.exceptionalmetals.com
Cover Board: DensDeck, Georgia-Pacific, www.densdeck.com

Website Provides Easier Navigation through Single-ply Roofing’s Metal Specialty Products

EXCEPTIONAL Metals has redesigned its website, exceptionalmetals.com, to help users experience the visual appeal and navigate through a user-friendly site. Featured products now have unique landing pages that contain corresponding literature and materials. Customers will benefit by the opportunity to learn about unique specialty products including the T-Edge, 2-Piece Snap-On Compression, skirted scupper and collector box.

The new website showcases EXCEPTIONAL Metals continuous drive to grow in the industry and create unique and innovative products that help contractors get on and off the roof faster. A true testament to this growth occurred in June as the company expanded manufacturing operations into Texas.

EXCEPTIONAL Metals, a division of Duro-Last Inc., manufactures high-quality metal products designed for use with any single-ply roofing system. Products include roof accessories, metal edge details, drainage systems, scuppers, collector boxes, pitch pans, custom-fabricated products, skirted vinyl-coated metal products, and standing seam roofing panels for architectural and structural applications. EXCEPTIONAL Metals is headquartered at its manufacturing facility in Saginaw, Mich., with additional fabrication locations in Carrollton, Texas; Grants Pass, Ore.; and Jackson, Miss. As a family-owned business, EXCEPTIONAL Metals is proud to be an American-made product.