Plate Marking Tool Designed to Increase Installation Efficiency

OMG Roofing Products introduces a plate marking tool designed to help roofers improve rooftop productivity by quickly locating and marking RhinoBond Plates installed under thermoplastic membranes.  

The new RhinoBond Plate Marking Tool is lightweight, simple-to-use and easy-to-maneuver. Simply roll the marking tool over a row of installed RhinoBond Plates. Every time it passes over a properly installed plate, the tool leaves a temporary mark on the surface of the membrane to identify the plate location. Plate marks are made with standard blue construction crayons and typically fade away within a few weeks.

The plate marking tool is compatible with all thermoplastic membranes regardless of type or thickness. In addition, the tool’s handle is reversible for quick direction changes, and lays flat for rolling under rooftop pipes and raised equipment such as air handling units. Other benefits of the new system include powerful sweeper magnets mounted on the front and back of the chassis that pick-up any metal debris on the roof. The tool is provided in a protective carrying case for easy handling and storage.

The RhinoBond System is designed for use with TPO and PVC roofing membranes. The System uses advanced induction welding technology to bond roofing membranes directly to specially coated plates that secure the insulation to the deck. The result is a roofing system with improved wind performance that requires fewer fasteners, plates, and seams, and zero penetrations of the new membrane.

For more information, visit OMGRoofing.com.

Metal Barrel Roof Tops the Rebels’ New Basketball Arena

The Pavilion at Ole Miss seats 9,500 fans.

The Pavilion at Ole Miss seats 9,500 fans. The building’s signature is its standing seam metal roof, which was manufactured by ACI Building Systems. Photos: Professional Roofing Contractors Inc.

The Pavilion at Ole Miss is a multi-purpose facility that is most famous for hosting the University of Mississippi’s basketball team. The arena cost approximately $97 million to build and seats 9,500 fans. The building’s signature arched metal panel roof was designed to complement the curved entrance and blend in with other architectural features on the university’s campus in Oxford, Miss.

Professional Roofing Contractors of Shelbyville, Tenn., was originally called in to assist with estimating the cost of the structure’s main roof, as well as a membrane roof system on the lower level. Upon final bid results, the decision was made to proceed with a standing seam metal roof on the upper portion of the building and a PVC roof on the lower level. Professional Roofing was the successful low roof bidder and selected ACI Building Systems to provide the standing seam roof materials and Sika Sarnafil to provide the PVC membrane roof materials. Professional Roofing installed both systems, with Jose Martinez as the crew leader for the membrane roofing portion and Dale Jones in charge of the metal roofing crew.

Larry W. Price, president of Professional Roofing, and Jonathan Price, the company’s vice president and the production manager on the project, oversaw the installation of 79,500 square feet of standing seam metal roofing and 46,500 square feet of PVC. There wasn’t much room for staging material on the jobsite, which didn’t give the company much room to maneuver. For the main roof, bundles of pre-cut metal panels were trailered in by ACI and loaded to the roof by crane.

“Logistics were complicated,” notes Larry Price. “Just getting a big enough crane in there and lifting the panels was difficult. Once we got the panels on the roof and they were situated, the roofers could just move ahead.”

Photos: Professional Roofing Contractors Inc.

Photos: Professional Roofing Contractors Inc.

Panels were installed with a 2-inch-high, double-lock standing seam, which was completed using a self-propelled mechanical seamer from D.I. Roof Seamers. The metal panels were curved into place by crews on the roof, who installed them over the staggered metal deck after it was covered with two 2-inch layers of polyiso insulation and Carlisle’s WIP 300 HT self-adhered underlayment. “The metal deck was segmented,” notes Jonathan Price. “We had to bridge some of those sections to make a nice, smooth curve.”

The scope of work included a large gutter at the roof edge. The gutter was 3 feet high and 2 feet wide, and crews from Professional Roofing flashed the gutter and lined it with the same Sika Sarnafil PVC used on the lower roof.

On the mezzanine level, crews installed a vapor barrier and mechanically fastened two 2-inch layers of polyiso insulation, as well as some tapered insulation for drainage. Once that work was completed, the 60-mil PVC was applied.

“Everything went pretty smoothly,” says Jonathan Price. “Logistics are usually tight on a new construction project, but once we adjusted to that, we just had to cope with the weather.”

“We had a lot of hot days and some rainy days,” Larry Price remembers. “Mississippi in the summer can get hot, hot, hot—and when it’s not hot, it’s raining.”

TEAM

Architect: AECOM, Kansas City, Mo.
General Contractor: BL Harbert International, Birmingham, Ala., Blharbert.com
Roofing Contractor: Professional Roofing Contractors Inc., Shelbyville, Tenn., Professionalroofingcontractors.com
Metal Roof Panel Manufacturer: ACI Building Systems, LLC, ACIbuildingsystems.com
PVC Roof Manufacturer: Sika Sarnafil, USA.sarnafil.sika.com

Hot-Air Welding Under Changing Environmental Conditions

The robotic welder’s speed, heat output and pressure should be properly programmed before the welding process begins. Photo: Leister.

The robotic welder’s speed, heat output and pressure should be properly programmed before the welding process begins. Photo: Leister.

Today’s most powerful hot-air welders for overlap welding of thermoplastic membranes are advertised to achieve speeds of up to 18 meters (59 feet) per minute. That’s fast enough to quickly ruin a roofing contractor’s day.

These robotic welders are digitally monitored to achieve consistent overlap welding performance, but they cannot adapt to changing environmental conditions automatically. It’s the contractor’s job to monitor and assess seam quality before the base seam is welded and when ambient temperatures or other factors potentially influence welding performance.

Successful hot-air welding requires the use of specialized, properly maintained and adjusted equipment operated by experienced personnel familiar with hot-air welding techniques. Achieving consistent welds is a function of ensuring that the roofing membrane surface is clean and prepared for heat welding, conducting test welds to determine proper equipment settings, and evaluating weld quality after welding has been completed.

Setting up hot-air robotic welders properly is the key to having a properly installed thermoplastic roof, and performing test welds is one of the most important steps. Making appropriate adjustments before the welding process begins ensures that the correct combination of welder speed, heat output and pressure is programmed into the robotic welder.

For most roofing professionals, these procedures have been firmly established in the minds of their crews and equipment operators through education and field training. But let’s not forget that Murphy’s Law often rules on both large and small low-slope roofing projects.

The frightening reality about using robotic welders is if they are set-up incorrectly or environmental conditions change, the applicator may weld thousands of feet of non-spec seam before anyone even bothers to check. If you probe for voids at the end of the day, it is probably too late.

If serious problems are discovered, the applicator must strip in a new weld via adhesive, cover tape, or heat welding, depending on what the membrane manufacturer will allow. If seams must be re-welded, the operator has to create not one, but two robotic welds on each side of the cover strip. The sheet will also need to be cleaned and re-conditioned no matter what method is used.

Can these errors be corrected? Absolutely. Except now the crew is in a real hurry because the roofer is working on his own time, and application errors tend to snowball under these conditions.

Reality Check

What goes on in the field is sometimes quite different than what one sees when hot-air welding thermoplastics under an expert’s supervision.To support this view, we asked four field service reps, each with a minimum of 35 years of roofing experience, to comment. The most senior “tech” has worked for six different thermoplastic membrane manufacturers in his career. Their names shall remain anonymous, but this writer will be happy to put readers in touch with them upon request.

Successful hand welding is a skill that is developed and refined over time. The correct selection of welder temperature and nozzle width can have a significant effect on the quality of the hand weld. Photo: GAF.

Successful hand welding is a skill that is developed and refined over time. The correct selection of welder temperature and nozzle width can have a significant effect on the quality of the hand weld. Photo: GAF.

So, let’s welcome Christian, Dave, Mark and Walter, and get straight to the point: Is the average roofing crew diligent enough when it comes to properly testing welds using industry best practices?

“I would say ‘probably not,” exclaims Walter. Dave just shakes his head as his colleague Mark adds, “I would have to say no.”

Considering the generally laudable performance of thermoplastic membranes over the last decade or so, we must interpret our experts’ opinions as suggesting the need for further improvement in hot-air welding techniques. Hence, the purpose of this article.

“There are a few outstanding issues causing bad welds,” says Walter. “These include welding over dirty or contaminated membranes; improper equipment setup; using crews with inadequate training; and knowing the difference between the weldability of various manufacturers’ membranes.”

Welding equipment consists of three main components: the power supply, the hot air welder (either automatic or hand-held), and the extension cord. A stable power supply of adequate wattage and consistent voltage is critical to obtaining consistent hot air welds and to prevent damage to the welder.

The use of a contractor-supplied portable generator is recommended, although house-supplied power may be acceptable. Relying on power sources that are used for other equipment that cycle on and off is not recommended. Power surges and/or disruptions and insufficient power may also impact welding quality. Proper maintenance of welding equipment is also of obvious importance.

“Contractors seem to never have enough power on the roof,” observes Mark. “The more consistent your power is, the more consistent your welds will be. Too many times, I’ve seen too many tools (hand guns, auto welder, screw guns and a RhinoBond machine) plugged into one generator.”

Generator-induced challenges on the jobsite are going to arise, agrees Christian. “But at least today there is more experience in understanding, dealing with, and ultimately preventing these issues,” he says.

Most TPO and PVC membrane suppliers also recommend using the latest automatic welding equipment, which provides improved control of speed, temperature and pressure. Our four experts generally agree that field welding performance has improved over the years and programmable robotic welders have helped. They also point to proper training and experience as crucial factors.

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OMG RhinoBond Projects Are Being Completed Across Europe

OMG Roofing’s RhinoBond System has left marks across Europe with more than 125 completed projects and more in the pipeline. Collectively, these projects represent more than 300,000 square meters (3.2 million square feet) of single-ply roofing.

“In last two years, the RhinoBond System has started to take off across Europe, as more roofing contractors have seen the roof performance benefits that the system can offer,” states Web Shaffer, vice president of marketing for OMG Roofing Products. “We have completed projects across Europe and we are expanding to new countries in the region, most recently, into South East Europe.”

RhinoBond is a method for installing thermoplastic and now also clean EPDM membrane. The system consists of a stand-up induction welding tool and magnetic cooling clamps. Contractors install roofing insulation using fasteners and specially coated plates designed specifically for the type of membrane being installed – PVC, TPO or Clean EPDM. Each plate is then bonded to the roof membrane installed over the top with the RhinoBond plate welding tool. The result is a roofing system that can provide wind performance with fewer fasteners, fewer membrane seams and zero penetrations of the new membrane.

The RhinoBond System is approved for use in Europe by many roof system providers, including Bauder, Carlisle/Hertalan, Danosa, Fatra, FDT, Firestone, GAF, IcoPal, IKO, Renolit, Sika, Siplast, and Soprema/Flag.

Headquartered in Agawam, Mass., OMG Roofing Products is a supplier of commercial roofing products including specialty fasteners, insulation adhesives, roof drains, pipe supports, emergency roof repair tape as well as productivity tools such as RhinoBond. The company’s focus is delivering products and services that improve contractor productivity and enhance roof system performance. For additional information, please contact OMG Roofing Products at (413)789-0252 or visit the OMG Roofing website.

A Michigan Contractor Is Challenged to Recreate a Roof’s 40-year-old Mural

Kevin Clausen has faced a lot of challenges during his 30 years at Great Lakes Systems, a Jenison, Mich.-based construction company specializing in single-ply commercial roofs. But when he received a call several years ago from a Kent County official about an unusual upcoming project, Clausen knew he might be taking on a challenge unlike any other.

Artist Alexander Calder created the 127-square-foot red, black and white mural painted on the roof of the Kent County Administration building.

Artist Alexander Calder created the 127-square-foot red, black and white mural painted on the roof of the Kent County Administration building.

Kent County is home to Grand Rapids, Mich. To understand the challenge that Clausen was about to face, it’s important to understand a little Grand Rapids history. In the late 1960s, swept along by the tide of enthusiasm for urban renewal, the city demolished 120 buildings in its aging downtown core and built a new City Hall and County Administration building, surrounded by a concrete plaza. The new government buildings were designed by architects who were shaped by mid-century ideas of good urban design: sleek, boxy single-use structures, easily accessed by automobile and, therefore, providing ample parking. Pedestrians were something of an afterthought.

At about the same time, the National Endowment for the Arts initiated its Art in Public Places Program. There was general agreement in Grand Rapids that the broad plaza in front of the new buildings seemed empty and generally lacked visual interest. The city applied for a grant to support the funding of a monumental sculpture to serve as a focal point for its new plaza and selected renowned sculptor Alexander Calder for the commission. Two years later, Calder’s sculpture—bright red, 43- feet tall, 54-feet long, 30-feet wide, weighing 42 tons—took its place on the central plaza. It was named “La Grande Vitesse”, which roughly translates into “Grand Rapids”. For obvious reasons, the broad plaza has been called Calder Plaza—and has been the focus of controversy ever since.

The Calder sculpture at ground level on the plaza inspired another important work of art in the area. The flat, unadorned roof of the administration building adjacent to the plaza was drawing attention for the wrong reasons. It was easily viewed from the nearby taller buildings, including the new City Hall, and several city administrators thought some sort of added visual element was necessary for the space. Calder again was pressed into service and designed a large mural for the roof of the administration building. When it was completed in 1974, the 127-square-foot red, black and white mural painted on the roof of the Kent County Administration building was the largest Calder painting in the world.

A DURABLE ROOF

Fast-forward three decades and the aging modified bitumen roofing membrane, which supported the Calder mural, had weathered badly and was in need of repair or replacement. The challenge? How to repair the roof and still preserve the Calder mural. Given the deteriorated condition of the roofing membrane, a complete tear-off was required. Basically, the task at hand was to replace the canvas of a painting and recreate the painting, maintaining its original appearance.

Great Lakes Systems, Jenison, Mich., was challenged to recreate the Calder mural on a new EPDM roof after tearing off the modified bitumen roof on which the mural was originally painted.

Great Lakes Systems, Jenison, Mich., was challenged to recreate the Calder mural on a new EPDM roof after tearing off the modified bitumen roof on which the mural was originally painted.

The team at Great Lakes Systems has a long track record of doing work for Kent County, including the jail, juvenile facility and several libraries. Therefore, county leaders turned to Great Lakes Systems when they realized they need- ed a creative solution to repair their unique roof. Clausen says the county wanted to preserve the mural, but a long-lasting, durable roof was a top priority. “They definitely wanted a high-quality roof,” he says.

The project faced other constraints, in addition to the painted surface. The administration building is located in a prominent spot in the middle of downtown Grand Rapids, near the museum dedicated to former President Gerald Ford and adjacent to two major expressways. No interruption of normal activities could be allowed—either on the plaza or in the building supporting the Calder mural. And—perhaps most challenging—Great Lakes Systems was given three weeks to complete the project before the inaugural ArtPrize competition would take over much of downtown Grand Rapids. That meant the team would have two weeks for the roof installation, leaving one week to repaint the mural. This was less than half the time usually required for a comparable project.

For Clausen, one part of the project was easy. He had used EPDM membrane on a variety of prior projects for county buildings, and county officials had been pleased with the results, especially the balance of cost-effective installation and long service life. “We looked at other membranes, given the nature of the project, but we always came back to EPDM, given its 30-year plus lifespan,” Clausen notes. “If we have to paint again, that’s OK, but we don’t want to reroof.”

For this project, fully adhered EPDM, as well as insulation ad- hered to the concrete deck, offered two important benefits: a painting surface that would be appropriate for the repainted mural and minimal noise (compared to a mechanically attached system) so that work in the building below could continue as normal.

Great Lakes Systems used 60-mil EPDM to replace the aging modified bitumen system. The 18,500-square-foot roof was backed by two layers of 2-inch polyiso insulation, and the EPDM membrane was covered with an acrylic top coat to provide a smooth surface for the new painting. The top coat matched the three colors of the mural—red, black and white. The red was a custom tinted acrylic paint deemed to be compatible with the EPDM membrane and the black and white acrylic top coat provided by the EPDM manufacturer.

Great Lakes Systems took aerial photos of the existing roof, created a grid of the roof and—scaling the design from the photos—recreated the mural exactly, a sort of large-scale paint- by-number approach.

Great Lakes Systems took aerial photos of the existing roof, created a grid of the roof and—scaling the design from the photos—recreated the mural exactly, a sort of large-scale paint- by-number approach.

A BEAUTIFUL ROOF

The Great Lakes Systems’ team applied a creative approach to recreate the mural, adhering carefully to the original design. Because the county used the same colors on its street signs as in the original mural, color codes were available to allow the team to access colors that were identical to those specified by Calder.

Great Lakes Systems took aerial photos of the existing roof, created a grid of the roof and—scaling the design from the photos—recreated the mural exactly, a sort of large-scale paint-by-number approach. The most intricate part of the painting was the layout. Although some free-hand painting had to be done along several jagged edges, the team painstakingly followed the scaled grid and applied chalk lines to outline the original design on the repaired roof. Roller applications were used at the border of the chalk lines to define individual spaces and mark the stopping and starting points for the different colors. Following this “outlining” work, the large areas were sprayed to complete the painting process. The three-man painting crew finished the job with several days to spare, helped along with very good weather.

The roofing project was an informal jump-start toward reimagining uses for Calder Plaza. This past summer, Grand Rapids residents were given the opportunity to voice their preferences for new landscaping for the plaza, provide input for activities that would attract more families and children, and generally make the space more pedestrian friendly. The new proposals are generating excitement and enthusiasm in Grand Rapids. As the new plans become reality, the citizens of Grand Rapids can be assured the Calder mural and the roof supporting it will be doing their part to add beauty and shelter to Calder Plaza and its buildings for decades to come.

Roof Materials

60-mil EPDM: Firestone Building Products Co.
2-inch Polyiso Insulation: Firestone Building Products
Black and White Acrylic Top Coat: Firestone Building Products

PHOTOS: Great Lakes Systems

Fleece-Backed Thermoplastic Membrane Exceeds Weathering Tests

KEE-Stone FB 60 fleece-backed thermoplastic membrane stands up agains harsh weather and UV radiation.

KEE-Stone FB 60 fleece-backed thermoplastic membrane stands up against harsh weather and UV radiation.

Garland has released the KEE-Stone FB 60 fleece-backed thermoplastic membrane which exceeds standard weathering tests and stands up against harsh weather and UV radiation. In accelerated weathering tests, KEE-Stone showed no signs of cracking or cratering even at 100 times magnification, which is 10 times more than the ASTM D 6745 standard requires. KEE-Stone’s compound, formulated using DuPont Elvaloy HP Ketone Ethylene Ester (KEE), provides resistance to UV degradation and heat resistance while retaining low-temperature flexibility, which translates into a lasting roof.

KEE enhances the performance of the PVC by permanently locking in its flexibility, eliminating plasticizer migration and allowing the membrane to remain tough and flexible throughout the entire lifecycle of the roof. Garland’s KEE-Stone membranes contain the KEE formulation throughout the entire sheet, further increasing its level of performance. The membrane is also reinforced with a polymer-coated scrim. The design of the scrim allows the KEE compound above and below the scrim to fuse together, imparting puncture, tear and tensile strength to the membrane.

Garland’s two-ply, hybrid KEE-Stone system will provide the protection of a traditional modified bitumen roof system with the appearance of a single-ply system.

For more information, visit here or call to be connected with your local Garland representative at 1.800.321.9336.

Palram Creates Two Positions to Enhance Its LEAN Journey

Palram Americas, a manufacturer of polycarbonate and PVC sheets and products, started the LEAN journey two years ago. Ideas like continual improvement, delivering value and reducing waste were introduced to the employees and the LEAN culture began weaving through the processes of the company. As part of its LEAN journey, Palram developed a vision to align all departments to a common direction by using guiding principles aligned in six supporting pillars. These values are defined and measured across all departments as: a safety first culture, respect for people, delivering value to our customers, high-quality standards, continuous improvement and long-term profitability.

Palram has created two new positions in efforts to bring a sharper focus to its LEAN journey. The Continuous Improvement Manager role will be filled by Enrique Gonzalez. He will champion the Palram LEAN initiative and has already immersed himself in creating new processes and suggesting improvements. The Voice of Customer Manager position will be filled by Johana Gonzalez. Johana’s new role will be aligned with the “Delivering Value to our Customers” vision pillar. In this role, she will work across the organization to analyze customer metrics while making process improvement recommendations as Palram strives for continuous improvement of service levels.

Enrique Gonzalez has an Industrial Engineering degree with more than 27 years of various roles aligned with LEAN and continuous improvement in a manufacturing environment. Johana Gonzalez has been employed by Palram in various roles for more than 13 years. She is currently working towards a degree in Business Administration. Palram is proud to have both of them helping to guide the LEAN journey.

Creating Visual Impact with Copper and Silver Roofing Membranes

Whether you’re re-roofing a historic building that needs to maintain its aesthetics or you’re working on a new roof construction that has to make a statement, there are many instances in which a building owner would want his or her roof to generate a specific architectural appeal. The most difficult part of this is balancing durability and beauty with cost. Roof systems today have evolved to solve this conundrum. Now, copper and silver synthetic PVC membranes are being used to achieve the desired appearance of a metal standing-seam roof at a fraction of the cost without sacrificing performance.

Alternatives to Metal Roof Systems

Michigan State University replaced the existing slate roof system with SOPREMA SENTINEL Copper Art to provide the desired appearance and required long-term performance.

Michigan State University replaced the existing slate roof system with SOPREMA SENTINEL Copper Art to provide the desired appearance and required long-term performance.


Copper and silver synthetic membranes are great cost-effective alternatives to metal roofs. As flexible synthetic systems, these roof membranes are economical and easy to install by conforming to complex geometries.

Certain synthetic PVC roof membranes on the market today are offered in a variety of colors, some of which can mimic the look of metal roofing. While these roof membranes offer the proven long-term performance of flexible polyvinyl chloride (PVC), they provide the metal appearance via the addition of pigments that can chalk or fade as the pigmented membrane ages, therefore losing the desired aesthetic feature.

Conversely, SOPREMA SENTINEL Copper and Silver Art PVC membranes incorporate copper or aluminum metallic powder into the PVC formulation, producing an enhanced metallic look. Unlike pigmented membranes, SENTINEL Copper Art provides the same weathering capabilities as traditional standing seam copper—the SENTINEL Copper Art will patina as a traditional copper roof would. Silver Art is unique because the color will not fade due to the addition of metallic powder, and its surface layer is factory embedded with an acrylic shield treatment to resist dirt pickup and chalking. Copper Art and Silver Art membranes provide the long-lasting aesthetic appearance and waterproofing abilities of a metal roof.

Applications for Copper and Silver Membranes

Copper and silver roof membranes are often used on buildings where aesthetics are important. Historic buildings, churches, schools, government buildings and army bases are a few examples of where this type of roof membrane has been installed. These buildings may require a particular appearance or designers may simply wish to update the appearance or provide some panache. Mansards or other areas of visible existing light-gauge metal roof systems may be present on these buildings and flexible copper and silver roof membranes may be used as an alternative aesthetic solution.

SENTINEL Silver Art met Glenside Public Library’s leak-free and architectural needs, plus the roofing contractor liked that the SENTINEL membrane was easy to install and looked great upon completion.

SENTINEL Silver Art met Glenside Public Library’s leak-free and architectural needs, plus the roofing contractor liked that the SENTINEL membrane was easy to install and looked great upon completion.

For example, since 2007, the slate roof of the Snyder-Phillips residence hall at Michigan State University had been leaking. The university needed to replace the existing slate roofing system with a new system that would meet the aesthetic requirements of the historic building. SOPREMA SENTINEL Copper Art was installed as a cap sheet to provide the desired appearance and the required long-term performance.

In addition, the Glenside Public Library had an existing standing-seam roof that was tied-in to a low-slope ethylene propylene diene monomer (EPDM) roof. The tie-in between the two materials was problematic and continuously leaked. The library wanted to preserve the standing-seam appearance, but the noise created by wind and rain on the metal roof was a concern.

SOPREMA SENTINEL Silver Art was selected because it could provide the desired look while eliminating the tie-in issues between the steep- and low-slope roofing materials. SENTINEL Silver Art met the library’s leak-free and architectural needs, plus the roofing contractor liked that the SENTINEL membrane was easy to install and looked great upon completion. In addition to its aesthetic appeal, SENTINEL Silver Art also offered the benefit of significant noise reduction when compared to the former metal roof system.

Roofing Technology Advancements

As roofing technology advances, the options for creating a desired aesthetic have evolved. SENTINEL PVC Copper and Silver Art are high-performance roof membranes that provide the appearance of metal with the flexible, long-term performance of PVC, without the weight, expense or complexity of a traditional metal roof.

Water Is Construction’s Worst Enemy

I have a water phobia. When I was very young I fell into a pool and nearly drowned. Consequently, I never learned to swim out of sheer fear. Despite my attempts to avoid it, water continues to haunt me. (See an article I wrote about my Chicago condo’s construction defects for some background.) It’s ironic I now live along the nation’s southernmost glacial lake. I love the view from our home, but the lake’s recreational opportunities are lost on me.

To further substantiate my negative feelings toward water, 2015 was an especially wet year for the Midwest. In mid-December, my Iowa town received 5 inches of rain in a day and a half. Our basement—where my office is located—flooded (for the second time since August). My husband bought the house (which he planned to make his lifelong bachelor pad) knowing the basement might leak during heavy-rain events. He never planned to have anything down there. Then I came along.

As this issue was coming together—around the same time our basement was soaked—I read a line in “Tech Point” that really resonated with me: “… water is construction’s worst enemy, so when it goes where it shouldn’t, it’s causing damage—seen or unseen.” I shared that line, which was written by Armand T. Christopher Jr., AIA, with my husband. The next week we hired a basement waterproofing contractor to solve our ongoing water problems.

Christopher’s story likely will resonate with you, as well. He and his team had recently installed a PVC roof system on a high-profile government building in central New Jersey. Six months after the install, a three-day nor’easter exposed numerous leaks in the building, which the client thought were coming from the new roof. The ensuing “detective work” Christopher’s team completed was tedious but uncovered the cause of the leaks and made Christopher and his colleagues heroes.

Christopher points out a nice feature of the roof’s thermoplastic cap sheet is areas where water had pooled within the roof system were dried and resealed with heat-welded target patches. Thomas W. Hutchinson, AIA, FRCI, RRC, CSI, RRP, builds upon this idea in his “From the Hutchinson Files” article. Hutchinson notes today’s “new age” roofs may not require removing all system components during reroofing. Instead, it may be in the customer’s best interest to consider restoration; roof-cover removal, enhanced with additional insulation; using the existing roof membrane as a vapor retarder; or membrane removal before installation of a new roof cover.

My husband and I seem to have found the best solution to our basement water problems. Although we’re not looking forward to the construction ahead, we are excited about all the things we can do with a dry basement. Right now, we’re envisioning a mini spa in which we can relax after a stressful workday—another welcome upgrade my husband never imagined for his “bachelor pad”.

Locating the Source of Water Intrusion Can Be Tricky

The building in question features one whole face that is an aluminum-framed glass curtainwall. The curtainwall extends up above the roof lines, slopes up (from the vertical) forming a peaked skylight, which then slopes back toward the roofs that were holding water.

The building in question features one whole face that is an aluminum-framed glass curtainwall. The curtainwall extends up above the roof lines, slopes up (from the vertical) forming a peaked skylight, which then slopes back toward the roofs that were holding water.

As architects/roof consultants, there is nothing we hate more than to get a call from a client who says, “My new roof is leaking.” Yet, that is exactly what happened to us not long ago. My firm had put a new thermoplastic PVC roof system on a high-profile government building in central New Jersey. The owner was my long-time client, and I ran the project, so I was intimately familiar with it and utterly shocked to get this call about six months after the project was completed. We had just experienced a three-day nor’easter that began on Thursday night and ran straight through to Monday morning when the client arrived at the building to find numerous leaking areas.

I responded by immediately going to the building. I was accompanied by the roofing system manufacturer. As the client led us around the building, water was dripping through suspended ceilings all over, which gave us the sinking (almost apocalyptic) feeling you hope to never know. However, when we went up to examine the roof, much to our surprise, there was no blow off; no seams torn; in fact, no apparent defects at all. Our thermoplastic cap sheet looked perfect on the surface.

On the upper roof, aluminum-framed sawtoothed skylights were dripping water when the team first arrived. This gave the only clue to where the “smoking gun” may lie.

On the upper roof, aluminum-framed sawtoothed skylights were dripping water when the team first arrived. This gave the only clue to where the “smoking gun” may lie.

What we did find, however, was large amounts of water trapped between this cap sheet and the 90-mil bituminous base sheet underneath. This was creating large water-filled blisters on the roof that looked like an old waterbed as you walked up to and around them. No matter how hard we looked we just couldn’t find defects in the membrane surface or at any of the flashing connections or terminations that could be causing this. There was, however, a likely suspect looming adjacent to and above our roofs. The building experiencing the roof leaks has one whole face that is an aluminum-framed glass curtainwall. It extends up above the roof lines, slopes up (from the vertical) forming a peaked skylight, which then slopes back toward these roofs that were holding water. On the upper roof, sawtoothed skylights of the same construction were dripping water when we first arrived. This gave the only clue to where the “smoking gun” may lie.

METHODOLOGY

Water was dripping from the saw- toothed skylights into a planter in the 4-story atrium. The client said that was typical with all hard rains. Armed with this clue, and no other apparent explanation for such a large amount of water intrusion, the owner engaged us to find out what indeed was the root cause of this problem.

On the upper roof, aluminum-framed sawtoothed skylights were dripping water when the team first arrived. This gave the only clue to where the “smoking gun” may lie.

On the upper roof, aluminum-framed sawtoothed skylights were dripping water when the team first arrived. This gave the only clue to where the “smoking gun” may lie.

In a couple days, the dripping subsided and most of the water blisters had dissipated or at least were reduced and stabilized. In the interim, I assembled a team consisting of a roofing restoration contractor (this is not a rip and tear production contractor but one especially geared to finding problems and making associated repairs), skylight restoration contractor and testing agency capable of building spray racks onsite to deliver water wherever it’s needed. With this team, I embarked on a systematic investigation that would make any “detective” proud.

First, we plugged the roof drains and let water pool on the roof until the en- tire surface was wet. Meanwhile, “spot-ters” inside the building were looking for any sign of water intrusion using lights above the dropped ceilings. When this showed nothing, we began constructing spray racks and running water for set intervals on every adjacent surface rising above and surrounding the lowest roof in question. We first sprayed the exposed base flashings, then rose up to the counterflashing, then further up the wall, then to the sill of the windows above, etc. Then we would move laterally to a new position and start again.

The team first sprayed the exposed base flashings with water, then rose up to the counterflashing, then further up the wall, then to the sill of the windows above, etc. Testing moved laterally to a new position before starting again.

The team first sprayed the exposed base flashings with water, then rose up to the counterflashing, then further up the wall, then to the sill of the windows above, etc. Testing moved laterally to a new position before starting again.

This proved painstakingly tedious, but we knew that making the building leak was not enough; we had to move slowly and systematically to be able to isolate the location to determine what exactly was leaking and why. It is important when applying water this way to start low and only after a set period move upward, so when water does evidence itself as a leak, you know from what elevation it came.

After an entire day of spraying the rising walls surrounding the first (low) roof area, we could not replicate a leak. Somewhat frustrated—and rapidly burning the testing budget—we began the second day focusing on the adjacent peaked skylight, which is more than 75- feet long.

The team first sprayed the exposed base flashings with water, then rose up to the counterflashing, then further up the wall, then to the sill of the windows above, etc. Testing moved laterally to a new position before starting again.

The team first sprayed the exposed base flashings with water, then rose up to the counterflashing, then further up the wall, then to the sill of the windows above, etc. Testing moved laterally to a new position before starting again.

Again, we started low, where our base flashing tied into the knee-wall at the base of the skylight, below the aluminum-framed sill. Still no leaks. Late in the day, when we were finally up to the glass level, we sprayed water from the ridge and let it run right down the glass onto our roof below. Finally, we found some leaking occurring at a skylight flashing to wall connection. OK, that was reasonable to anticipate and easy to correct.

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