Solar Roof Energy Is the Answer for Mega Cities of the Future

Seven billion people will live and work in urban areas by 2050 and the demand for energy for all these people will be huge. Local production of energy will be needed with building-integrated photovoltaics (BIPV) key to make cities at least partially self-sufficient with energy. Rapid development in thin-film solar cell efficiency strengthens the business case for BIPV with great opportunities for suppliers of roofing materials and construction companies.

The electricity produced by ‘roof solar energy’ could be used for heating, cooling, running office machinery or even fed back to the grid, earning the building owners money.

The electricity produced by ‘roof solar energy’ could be used for heating, cooling, running office machinery or even fed back to the grid, earning the building owners money.

More than half of the planet’s population lives in urban regions today. This will grow to 75 percent in the next 30 to 35 years. That would mean 7 billion people living in more or less congested areas, all needing shelter, food—and lots of energy.

There is a growing consensus that the mega cities in the future cannot rely entirely on energy produced far away. Besides supply constraints, there are energy losses in the transport of the electricity; logistical nightmares; security issues; and, of course, environmental concerns.

There is a very healthy debate about distributed energy generation, often defined as electricity generation from many small sources. This discussion must be encouraged. We simply cannot solve the energy challenges of tomorrow with energy solutions of yesterday.

The distributed energy discussion has so far mainly centered on local smaller power plants, district energy, more efficient electricity distribution, the ‘smart grid’, etc. That is good. But we must also talk about the potential for local production of renewable energy by the end users on a micro scale, the very individuals who consume all this energy.

What do the end users have in common? Well, they all need a roof over their heads, at home and at work. These roofs can produce renewable energy! So the building industry can play a major role in solving mega cities’ energy challenges.

Building-integrated photovoltaics can be incorporated into the construction of new buildings as a principal or ancillary source of electrical power, and existing buildings may be retrofitted with similar technology.

Building-integrated photovoltaics can be incorporated into the construction of new buildings as a principal or ancillary source of electrical power, and existing buildings may be retrofitted with similar technology.

Look at an aerial image of a city and you will see an area densely covered by buildings—crisscrossed by roads and the occasional recreational area. All these buildings—houses, apartments, garages, offices, factories, schools and municipal buildings of all sorts—have roofs. New development in solar energy has transformed all these roofs—and even walls—into potential giant solar energy receivers.

The electricity produced by ‘roof solar energy’ could be used for heating, cooling, running office machinery or even fed back to the grid, earning the building owners money.

What I call ‘roof energy’ is building-integrated photovoltaics (BIPV), one of the fastest-growing segments of the photovoltaic industry. Photovoltaic materials are used to replace (or are added onto) conventional building materials in not only roofs, but also skylights and facades. They can be incorporated into the construction of new buildings as a principal or ancillary source of electrical power, and existing buildings may be retrofitted with similar technology.

Traditional wafer-based silicon solar cells are efficient but rigid, thick and heavy, ideal for large solar parks in sparsely populated areas but not in dense cities. They are too heavy for most roofs. However, thin-film solar cells made out of a copper-indium-gallium-selenium metal alloy (CIGS) are thin, light and flexible. They can be made frameless, can be bent, and are ideal for buildings and other structures that are uneven, moving or weak.

The business case for thin-film solar cells is strengthening rapidly since they are becoming increasingly efficient. A Swedish supplier of thin-film solar cell manufacturing equipment has managed to increase the aperture efficiency (the area on the solar panel that collects energy) from 6 percent four years ago to 11 percent two years ago and a record breaking 17 percent today by using a revolutionary all-dry, all vacuum process where all layers are deposited by sputtering.

An office, school, storage facility or factory with a flat roof in a Mediterranean country like Italy could annually yield 1,250 kWh from every kW installed, at a production cost of 7.2 U.S. cents. The production cost would decrease if the roof is slanted by up to 20 percent for an optimal 35-degree angle. The production cost would obviously be higher in colder countries and lower in countries nearer the equator. But even in Sweden the production cost could be as low as 8 cents.

Thin-film solar cells made out of a copper-indium-gallium-selenium metal alloy (CIGS) are thin, light and flexible.

Thin-film solar cells made out of a copper-indium-gallium-selenium metal alloy (CIGS) are thin, light and flexible.

A production cost of 5 to 10 cents is well below the current—not to mention the expected future—electricity prices. There are great variations in the price of electricity today, but many users pay between 10 and 30 cents per kWh (including taxes). Commercial and residential users pay even more.

The $100bn global roofing material market is in a healthy state, growing at 3.7 percent per annum and driven by an uptick in residential building construction (especially reroofing) in developed and developing markets. Here is an excellent opportunity for architects, roofing material suppliers and construction companies to take a leading position in what is destined to be the material of choice for urban planners in the future.

Thin-film BIPV solar energy solutions can be made light and are flexible. They can be fitted or retrofitted onto roofs without perforating the roofs and can be curved or bent. Installation is easy and cost-efficient with no racks or ballast needed. There are no weight constraints and no access limitations (you can walk on the panels). And they can be integrated on bitumen and TPO membranes.

Selling roofing solutions and electricity together opens up to completely new business models: suppliers can offer a discounted roofing price in combination with a stable and independent supply of electricity. Customers can secure electricity price—and get a new roof.

Municipalities and city planners in today’s and tomorrow’s mega cities will make efforts to make their cities greener and more sustainable. It is no wild guess that green buildings with ‘roof energy’ systems will get preferential treatment in public tenders and maybe even subsidies. Building owners will like the prospect of lower energy costs.

So the question to the world’s architects, roof manufacturers and construction companies is: Do you feel lucky? Do you feel confident enough to keep doing business as usual, selling traditional roofs to consumers who might sooner than expected demand energy-producing and cost-saving roofs and buildings? Or will you grab an unparalleled opportunity to gain market share by offering state-of-the-art products that will change the world or at least the way the world’s urban population powers their daily lives?

For me, the answer is simple: If end users can produce part of the energy consumed in a sustainable fashion where they live and work, that would go a long way toward solving the energy and climate challenges of the future. Flexible, efficient, thin-film solar cells for buildings are an integral part of this solution.

Waterproof and Maintenance-free Roof Penetrations

The fewer people with access to the roof, the better chance the roof has at meeting the basic expectation of keeping the elements out of the building.

Pitch pockets are flanged, open-bottomed metal containers, placed around roof penetrations.

Pitch pockets are flanged, open-bottomed metal containers, placed around roof penetrations.

Because they make their living on the roof, commercial roofing installers know how to complete a watertight system, one that does not allow damaging moisture into the building. Unfortunately, when the roofing installer finishes the job, more work, perhaps by other trades, most notably HVAC contractors, may be done with possible impacts on the roofing membrane.

Someone has to get on the roof to install that equipment and at that point it’s going to be an equipment installer, not a roofing installer. It’s important to be aware of who is doing what on the roof!

Attaching equipment to the building structure, through the roof, is the most efficient method of attachment, but often such work is done without consideration of waterproofing concerns. Any attachment penetration must not compromise the integrity of the roofing system.

This is why RoofScreen Manufacturing got into the business: to discover and develop a better method for leak-proof attachment for all types of roofing and building structures.

the caulk and band method, commonly used on round penetrations, which employs a single-ply or soft lead pipe flashing around the penetration.

The caulk and band method is commonly used on round penetrations and employs a single-ply or soft lead pipe flashing around the penetration.

The equipment installer has options. A traditional penetration waterproofing system is what is known as the pitch pocket. Pitch pockets are flanged, open-bottomed metal containers, placed around roof penetrations. They are filled with coal tar pitch, hot asphalt, grout or other chemical sealants. They are effective around odd-shaped penetrations but require maintenance, which means slapping on more sealant when it leaks.

Another method is the caulk and band method, commonly used on round penetrations, which employs a single-ply or soft lead pipe flashing around the penetration. Near the top of the flashing is an adjustable draw-band that clamps the flashing to the penetration. Caulking is applied around the top of the flashing to make the final seal.

Both practices are accepted by the National Roofing Contractors Association. The problem is both require annual or semi-annual maintenance to check if the sealant has cracked or separated from the penetration and addition of sealant as necessary.

RoofScreen offers a patented engineered and leak-proof roof attachment system to ensure the integrity of the roofing system. It starts with a 6- by 6-inch steel base support, available in a variety of lengths to accommodate any insulation thickness. The support is attached with bolts or lag screws to the roof structure through the interior of the base support. Specially fitted flashing boots are then installed and roofed in by a qualified roofing contractor. After roofing is completed, a self-adhesive EPDM gasket strip is applied around the top of the flashing, which provides added protection from snow, ice and splashing water. The final step is to install the Base Cap Assembly, which counterflashes 2.4 inches over the flashing and creates a seal by compressing the gasket. This watertight structural mounting point is ideal for mechanical equipment screens, equipment platforms and solar panel racking systems.

This watertight structural mounting point is ideal for mechanical equipment screens, equipment platforms and solar panel racking systems.

A watertight structural mounting point is ideal for mechanical equipment screens, equipment platforms and solar panel racking systems.

Many roofing manufacturers require penetration flashings to extend a minimum of 8 inches above the roof surface. RoofScreen has performed successful independent lab testing on its roof attachment system with only a 3-inch flashing height and had no leaks. Ultimately, it’s up to the roofing contractor and the roofing manufacturer to determine the flashing height in relation to the roof. Consult with both, especially if there is a roofing warranty involved.

If a base support needs to be raised to meet a required flashing height, RoofScreen offers 5-, 9- and 12-inch versions of the base support, plus 3- and 4-inch extensions. A taller base support should, in most cases, provide enough clearance for the amount of insulation being used. It should be noted the height of base supports impacts the overall design of the frame. RoofScreen provides fully engineered solutions incorporating all equipment screen variables.

In addition to installing a patented engineered leak-proof roof attachment system, RoofScreen eliminates the need for periodic maintenance. There will never be a need to add temporary caulking. With no need for maintenance, there’s one less reason for anyone being up on the roof to compromise the roofing system. That’s a good thing.

Ballasted EPDM Roof Has Been in Service Since 1979

Rob Nelson is a 44-year-old software consultant who owns a multi-tenant, 137,000-square-foot building in Kingston, Pa. Rob’s dad bought the building in 1985, when it was an abandoned cigar factory and Rob took over management of it in 2002. He considers it to have been a good investment for many reasons. It has attracted a variety of tenants and currently houses about 25 businesses, including small, single-office enterprises, an engineering firm and a home-health nursing business. Rob’s family operates a furniture business and an indoor self-storage facility in the building, as well.

Roof Consultant Mark Sobeck inspects a 35-year-old ballasted EPDM roof on a multi-tenant building in Kingston, Pa.

Roof Consultant Mark Sobeck inspects a 35-year-old ballasted EPDM roof on a multi-tenant building in Kingston, Pa.

Besides its track record of attracting tenants, Rob also values his building for another very important reason: its ballasted EPDM roof has been in place since 1979. If you do the math, that’s 35 years. And Rob’s roofing consultant, Mark Sobeck, based in Wilkes-Barre, Pa., says he can realistically expect his building to get another 10 or 15 years of protection from the roof.

Rob and Mark emphasize that maintenance has been important to the roofing system as a whole. One-third of the original roof has been replaced for reasons not related to the membrane performance, and the flashing and expansion joints have been replaced on the original section of the roof. But the membrane itself, according to Sobeck, is still in great shape. “It’s amazing how the EPDM rubber is still lasting. At thirty-five years, it’s still stretchy and pliable and looks good.”

Nelson’s experience with the longevity of his roof is backed up by in-depth testing by the EPDM Roofing Association (ERA). ERA commissioned studies of five EPDM roofs that had been in use for between 28 and 32 years. The roofs, ballasted and fully-adhered, were first inspected in the field, and then small samples of the EPDM membrane were sent to Momentum Technologies, a testing facility for the roofing industry in Uniontown, Ohio. Five key performance characteristics of the samples were tested: elongation, tensile strength, cross-direction thickness, machine-direction thickness and factory-seam strength. The lab results showed that all the samples had physical characteristic properties above or just below the minimum physical characteristics of a newly manufactured 45-mil EPDM membrane. Put another way, after three decades of use, they were performing like new. Roofing experts point out that installation materials and methods have advanced considerably in the last 30 years, giving new roofing systems an expectation of an even longer service life.

A roof that lasts a long time will deliver obvious financial savings to building owners. In an era when environmental benefits must also be considered, experts say that its important to look at sustainability in the broadest possible terms. “If a roof lasts a very long time,” says John Geary, director of Education and Industry Relations for Firestone Building Products and chairman of the board of ERA, “that’s very good news for the environment. Compared to a roof that has to be replaced every 10 years or so, the choice of EPDM means fewer resources are ultimately used in the manufacturing and maintenance of the roofing system. Additionally, EPDM can be recycled, so it also means less materials winds up in a landfill.”

Rob Nelson may not have seen the results of EPDM lab tests, but he sees proof of the durability and longevity of EPDM every time he visits his building. “It’s pretty wild and definitely surprising that we are still kicking along after 35 years,” he says. Given consultant Mark Sobeck’s projections, Nelson can expect another 15 years or so of “wild” service from his EPDM roof.

French Kings, Solar Power and Sustainability

Louis XIV is not a frequent reference point in today’s discussions about the world’s energy and sustainability paths. However, this longest ruling French monarch (1643-1715) was known as the “Sun King” as he often referred to himself as the center of the universe and was enamored of the sun itself. He also was the builder of Versailles, the construction of which was viewed as very innovative for its day with gardens and roads that Louis XIV arrayed in a pattern to track the sun’s movements.

2014 International Solar Decathlon in Versailles, France. PHOTO: SDEurope

2014 International Solar Decathlon in Versailles, France. PHOTO: SDEurope

With this in mind, it is not such a stretch to understand why the organizers of the 2014 International Solar Decathlon chose the Versailles grounds in which to hold this extraordinary exhibition, from which I have recently returned. The 15-day exhibition featured more than 20 universities from around the world, with Brown University/Rhode Island School of Design and Appalachian State University as the two U.S. competitors.

During each day of the competition, the entrants were subjected to judges’ inspection to assess performance in categories, such as architecture, communications (ability to literally tell their house’s story to press and visitors), energy efficiency, engineering and construction, and sustainability.

PIMA’s sponsorship of Appalachian State and the providing of polyiso insulation by Atlas Roofing to ASU demonstrated the role high-performance insulation plays in the future of the built environment.

However, it is not individual product performance that most impresses the visitor to these extraordinary homes. Yes, they all make exceptional use of the solar power generated by their installed PV systems (they are limited by the rules to only 5 kWh of electricity production from which they must run refrigerators, air conditioning, washers and dryers) and each home has an array of innovative products. But it is the synergistic result of the products’ application combined with the unbelievable ingenuity of the students and professors that excited me the most.

2014 International Solar Decathlon PHOTO: SDEurope

The “decathletes” at the 2014 International Solar Decathlon in Versailles, France. PHOTO: SDEurope

Some buildings were representative of new construction. For example, the ASU entrant was a modular townhome with the potential to assemble into a collective urban building.

In addition, recognizing that existing buildings are the greatest energy challenge, the effort to improve our world’s retrofit capabilities truly caught my eye. For example, the Berlin Rooftop Project focuses on abandoned rooftop space in that city to create studios for younger urban dwellers, while the Dutch (Delft University) addressed the poorly insulated townhomes that make up over 60 percent of Dutch homes by applying a “second skin” while including a garden capability within the home.

The several days I spent at the event were educational, but nothing was more inspiring than speaking with the students themselves. Be they from Chile, France, Germany, Japan, the United States or any of the other countries involved, their passion was compelling. The intellect and commitment of these future architects, engineers, designers and urban planners to finding sustainable solutions for the planet gives me a distinct optimism for our future.

Roof Systems Contribute to Success of 2014 FIFA World Cup

The Federation Internationale de Football Association (FIFA) World Cup is the king of soccer competitions, so it’s only appropriate that four of the 2014 venues are crowned with roof systems that are as strong as the competition inside the venues. Three venues feature lightweight tensile structures from Birdair and the fourth includes polycarbonate skylights from PALRAM.

Estadio Mineirão

Estadio Mineirão, built in 1965 and listed as a national monument of Brazil, underwent a three-year modernization project to prepare for hosting six of the FIFA World Cup matches.

Estadio Mineirão, built in 1965 and listed as a national monument of Brazil, underwent a three-year modernization project to prepare for hosting six of the FIFA World Cup matches.

Estadio Mineirão, built in 1965 and listed as a national monument of Brazil, underwent a three-year modernization project to prepare for hosting six of the FIFA World Cup matches. It was transformed into a modern stadium with a new tensile roofing system from Birdair. The 141,000-square-foot tensile roof was added to the concrete upper tier of the stadium to provide shelter for 70,000 spectators while meeting aesthetic, acoustic and environmental impact requirements.

Birdair fabricated and supplied TiO2-coated PTFE, a Teflon-coated woven fiberglass membrane for the facility. Taiyo Birdair do Brasil, a subsidiary of Birdair, was responsible for installing the PTFE tensile membrane. TiO2 (titanium dioxide), a non-toxic and flame-resistant coating allows fabric to break down any organic materials that settle on the membrane, such as dirt. It is capable of withstanding temperatures from -100 F to 500 F, is unaffected by UV rays, and requires less maintenance to retain its appearance due to its self-cleaning capabilities. Ultimately, this TiO2 membrane is an economic and environmentally sustainable renovation that will provide fans with much-needed comfort, as well as improve a national landmark.

Estádio Nacional

Estádio Nacional expanded its capacity from 42,200 to 70,042 to host seven World Cup matches.

Estádio Nacional expanded its capacity from 42,200 to 70,042 to host seven World Cup matches.

Estádio Nacional, originally built in 1974 and located in Brazil’s capital, also underwent major reconstruction for the World Cup, expanding its capacity from 42,200 to 70,042 to host seven World Cup matches. Birdair fabricated and supplied the PTFE fiberglass membrane, clamping and hardware for the facility. The consortium Taiyo Birdair do Brasil ­Entap ­Protende was responsible for installing the entire roof’s steel and cable structure, including the PTFE outer roof and liner membrane. The project involved building a new lower tier and retaining the upper tier with the addition of a new 920,000-square-foot double-layer suspended tensile roof.

Fonte Nova Stadium

Fonte Nova Stadium's oval-shape roof design will provide cover for 50,000 spectators during each of the six games it hosts during the tournament.

Fonte Nova Stadium’s oval-shape roof design will provide cover for 50,000 spectators during each of the six games it hosts during the tournament.

Birdair, through Taiyo Birdair do Brasil (TBB) Ltda., additionally was awarded a subcontract for the roof construction of Fonte Nova Stadium in Salvador, Brazil. The stadium is modeled on its predecessor, the Estadio Octavio Mangabeira, and features three levels of seating with a view of the magnificent Dique do Tororó. Its oval-shape roof design will provide cover for 50,000 spectators during each of the six games hosted at Fonte Nova during the tournament.

Birdair’s project role consisted of detailing, fabricating and supplying PTFE, a Teflon-coated woven fiberglass membrane that makes up the facility’s lightweight tensile roofing system. Taiyo Birdair do Brazil fully installed the PTFE membrane for the 301,399-square-foot tensile roof. The facility’s tensile roof provides natural daylighting, solar shading and minimal maintenance, as well as contributes to the unique aesthetics of the new Fonte Nova Stadium.

PTFE fiberglass membrane structures have received increased global recognition as green living is becoming more important. Upon completion, Estádio Mineirão and Estádio Nacional applied for LEED certification, which is given to projects that use less materials and increase daylighting to conserve resources and increase sustainability.

Plácido Castelo

PALRAM qualified for its second consecutive World Cup games, this time covering the Plácido Castelo stadium with SUNTUF 2-millimeter-thick roofing.

The Plácido Castelo Stadium in Fortaleza, Brazil, features SUNTUF corrugated polycarbonate.

The Plácido Castelo Stadium in Fortaleza, Brazil, is popularly known as “Castelão”, part of a local tradition to nickname popular stadiums.

The Plácido Castelo Stadium in Fortaleza, Brazil, is popularly known as “Castelão”, part of a local tradition to nickname popular stadiums. Owned by the Brazilian government and inaugurated in 1973, the stadium was revamped for the 2014 World Cup.

“The Palram Project Support Team was given the task of providing an architectural solution for the roof skylight. The proposal implemented was a 7,000-square-meter transparent front edge roofing specially designed to allow natural daylight on the pitch,” says Tal Furman, Palram chief engineer.

The solution offered by PALRAM was based on its continuing worldwide stadium roofing trend using SUNTUF transparent corrugated polycarbonate sheets, as a front edge covering, providing a perfect cost effective watertight solution.

A 7,000-square-meter transparent front edge from PALRAM was specially designed to allow natural daylight on the pitch.

A 7,000-square-meter transparent front edge was specially designed to allow natural daylight on the pitch.

For the Castelão stadium roof, PALRAM specified 9-meter single length SUNTUF corrugated polycarbonate sheets that cover the entire roof length, thus ensuring long term transparency for the skylight and reduced risk for leakage.

The Arena Castelão will host six World Cup matches, including a first round match between Brazil and Mexico and one of the quarter-finals. It was the first Brazilian Stadium to obtain the LEED certification. Since its re-inauguration, the Arena Castelão has hosted more than 50 matches of the local league and of the Brazil Cup. The stadium also hosted matches of the 2013 FIFA Confederations Cup and world-class concerts from artists like Paul McCartney and Beyoncé.

As part of PALRAM preparation for the World Cup, a polycarbonate roofing solutions professional seminar was held in front of Brazil top architects, engineers and construction professionals by Mr. Michel Allouch, Palram V.P. Marketing and development. As a result of this seminar, the same solution was implemented by PALRAM project team as well at the new Palmeiras Stadium in São Paulo, although this stadium is not hosting the World Cup games.

For over 50 years, PALRAM has been a global leader in manufacturing extruded thermoplastic sheets, offering an extensive product line for consumer, architectural, construction, sign & display, and agricultural applications.

The 20th FIFA World Cup is scheduled for June 12 through July 13, 2014 in 12 different Brazil host cities.

New Roof Must Last as Long as the Solar Panels It Supports

As thousands of Silicon Valley employees exited Hewlett-Packard (HP) global operations headquarters to head home for the evening, a crew of 25 roofers–under the glare of temporary spotlights–toiled diligently. They were fastening thousands of 1/2-inch DensDeck Prime coverboards to the 10-year-old insulation system covering the building’s metal deck.

Originally planned to be white, Hewlett-Packard ultimately selected a tan-colored membrane, to reduce glare because two levels of the building have glass-to-ceiling windows that allow visual access to the roof.

Originally planned to be white, Hewlett-Packard ultimately selected a tan-colored membrane, to reduce glare because two levels of the building have glass-to-ceiling windows that allow visual access to the roof.

Soon after, they adhered a single-ply, fleece-faced, tan-colored Sika Sarnafil EnergySmart roof membrane to the DensDeck Prime boards, creating a state-of-the-art 300,000-square-foot reroof. The added protection was much-needed, as it provided the durability and compressive strength to safely accommodate a massive system of solar panels that were installed atop 85 percent of the roof.

“We chose DensDeck Prime because it provides the best support for the new membrane, the existing roof and all the (solar) equipment that will go on top of it,” explains Steve Nash, vice president of Waterproofing Associates, who designed the reroof system in conjunction with Ted Christensen of Independent Roofing Consultants, and selected the materials to make it work. “With all the weight that will be bearing directly on the roof membrane, we need the ultimate roof substrate.”

Installing the massive, electricity-generating system of solar panels was an intricate endeavor, especially because its presence will complicate any repairs to the roof during the solar energy system’s anticipated 25-year life cycle. The building owner called on Nash to create a roof with a life cycle that would mirror the life of the solar panels.

The building owner desired a roof with a life cycle that would mirror the 25-year life span of the solar panels, which cover 85 percent of the roof.

The building owner desired a roof with a life cycle that would mirror the 25-year life span of the solar panels, which cover 85 percent of the roof.

“If the roof were to need repairs, the solar panels would have to be disassembled and out of service until the repairs are finished. And that can’t happen,” Nash adds. “Basically, we have to build a virtually maintenance-free roof.”

Protection—Above and Below

Cost-effective because of its energy efficiency and high levels of dimensional stability, the Sika Sarnafil G410 membrane is frequently installed over an underlayment of DensDeck Prime because its surface treatment provides a stronger bond for adhered membrane applications. Also, DensDeck Prime roof boards’ high pounds per square inch (PSI) compressive strength is an advantage as a durable platform for roofs with heavy equipment, like solar panels, on top.

Adding further complexity to the building’s new roofing system was the fact that the owner chose only to replace the original membrane—from another manufacturer—that had sprung a number of leaks in recent years. Keeping the remainder of the original roof—2 inches of fiberglass insulation, a built-up gravel surface and 1/2 inch of fiberboard—saved considerable time and money, as well as avoided having to send thousands of pounds of materials to landfills.

However, it did require adding the layer of DensDeck Prime to do double duty: carefully protect the layers of the original roof that would remain while forming the foundation for the Sika Sarnafil membrane.

Upon completion of the five-week project, which was conducted only at night and on weekends so the noise wouldn’t interrupt the HP employees during normal work hours, the new roof is aesthetically pleasing. Originally planned to be white, the owners ultimately selected a tan-colored membrane, to reduce glare because two levels of the building have glass-to-ceiling windows that allow visual access to the roof.

Nash notes the new roof’s beauty will only be exceeded by its durability. “With thousands of pounds of solar panels sitting on top of it, the roofing membrane cannot fail. So you get the best materials available to make it last—and that’s exactly what we’ve done.”

Reroofing Is One of the Few Opportunities to Improve the Built Environment

All of us get misled by catch-phrases, like “Save the Planet” or “Global Warming” or “Climate Change”. Although phrases like these are well intended, they can be misleading; they really are off topic. Something like “Save the Humans” is more to the point and truly the root of the entire sustainability movement. Let’s face it: The efforts to be more green are inherently aimed at a healthier you and me, as well as our children’s and grandchildren’s desire for continued healthful lives and opportunities.

The existing PVC roof on the GM After Sales Warehouse, Lansing, Mich., was removed and recycled into new PVC roofing material, a portion of which was reinstalled on this project and helped it achieve RoofPoint certification.

The existing PVC roof on the GM After Sales Warehouse, Lansing, Mich., was removed and recycled into new PVC roofing material, a portion of which was reinstalled on this project and helped it achieve RoofPoint certification.

The discussion about green and sustainability needs some context to make it real and effectual. The question to ask is: How does green construction help humans live a healthier and happier life? The answer is: It is because of the co-benefits of building (and living) in a more environmentally appropriate way.

One key component of building environmentally appropriate buildings is that, collectively, we use less energy. Less energy use means no need to build another power plant that creates electricity while spewing pollution into the air. Less pollution in the air means people are healthier. It also means the water and soil are less polluted. We drink that water and eat what grows in the ground. We also eat “stuff” from the rivers, lakes and oceans. Healthier people means reduced costs for health care. Reduced sickness means fewer sick days at the office, and fewer sick days means more productivity by employees—and, dare I say, happier employees all because of the environmentally appropriate building, or a “human appropriate” building.

So what does all this have to do with roofs? Rooftops, because they are a significant percentage of the building envelope, should not be overlooked as an important and truly significant energy-efficiency measure. Building owners and facility managers should always include energy-efficiency components in their roof system designs. There are few opportunities to improve the building envelope; reroofing is one of those opportunities, and it shouldn’t be missed.

According to the Center for Environmental Innovation in Roofing and building envelope research firm Tegnos Inc., roof systems have the potential to save 700-plus trillion Btus in annual energy use. Too many roofs are not insulated to current code-required levels. If our rooftops were better insulated, these energy-saving estimates would become reality. Imagine the co-benefits of such a significant reduction in energy use!

The RoofPoint certified Bucks County Community College roof, in Perkasie, Pa., features a high-performance multi-layer insulation system that provides high levels of energy efficiency. Staggered joints break thermal discontinuities and a coverboard provides R-value and a durable surface.

The RoofPoint certified Bucks County Community College roof, in Perkasie, Pa., features a high-performance multi-layer insulation system that provides high levels of energy efficiency. Staggered joints break thermal discontinuities and a coverboard provides R-value and a durable surface.

But how do we know we’re doing the right thing? RoofPoint and the RoofPoint Carbon Calculator will help. The RoofPoint Carbon Calculator uses seven inputs to compare an energy-efficient roof with a baseline roof: insulation, thermal performance, air barrier, roof surface, rooftop PV, solar thermal and roof daylighting. The outputs from the Carbon Calculator are total roof energy use, energy savings due to the energy-efficient roof design, energy savings during peak demand, and CO2 offset for the energy-efficient roof design. This can be used to compare an existing roof (the baseline roof) to a new roof design (the energy efficient roof), and this will help verify the energy savings and reduction of carbon output. It’s an excellent tool for verifying how green a new roof can be.

And don’t just take my word on this co-benefits idea. The Economist published an article about the EPA and rulings on interstate pollution. The article cited a claim that by this year, 2014—if pollution rates were half of those in 2005—hundreds of thousands of asthma cases each year could be prevented and nearly 2 million work and school days lost to respiratory illness could be eliminated. And just think, improving your roof’s energy efficiency is key to the reduction of power-plant use and the pollution that comes from them. So, yes, roofs can help your kids and your grandkids be healthy and happy.

Transite Roofing: Friend or Foe?

As Transite, or Asbestos-containing, Roofs Come to the End of their Life Cycle, Contractors Should Know When Retrofitting Is an Option

The use of asbestos dates back thousands of years. For millennia, cultures across the globe embraced asbestos’ super-strengthening properties. Asbestos’ popularity peaked in the late 19th century during the Industrial Revolution when commercial asbestos mines sprung up across the U.S. and Canada. Before its carcinogenic properties were discovered, asbestos was used in hundreds of applications, including walls, roofs, coatings, fireplaces, shingles, insulation, pipes, furniture, paper products, automobile parts, fabrics and packaging. In the construction industry, in particular, it was considered a “super-product.” Whether mixed as a binder with cement or used as a coating on steel panels, asbestos is insulating, non-combustible, corrosion-resistant, inert, humidity-tolerant and sound absorbent.

One major application of asbestos over the past 100 years has been transite roofing panels. Asbestos was essentially used as a binder in cement slurry and then formed into profiled or flat sheets. Transite roofing panels can still be found across the country; many are still in place after 50, 60 or even 70 years of life. Because transite panels acquired asbestos’ super-strengthening properties, they made (and in some cases continue to make) ideal roofing for foundries, forges, chemical plants, paper plants, wastewater treatment plants and sewage facilities. The roofing material withstands high heat, chemical emissions, humidity and other elements emitted by these facilities that other building products could not tolerate.

Transite roofing panels can still be found across the country; many are still in place after 50, 60 or even 70 years of life.

Transite roofing panels can still be found across the country; many are still in place after 50, 60 or even 70 years of life.

Despite the strength of asbestos, even transite roofs can deteriorate or require renovation. In fact, most roofing contractors have encountered or will soon encounter transite roof jobs. The job where transite is in good condition with no airborne particles may be a perfect candidate for a retrofit.

(For the purposes of simplicity, this article uniformly refers to corrugated, asbestos-containing cement roofing sheets as transite. Professionals may also encounter names like 4.2 cement asbestos or corrugated cement. It’s important to note not all corrugated cement roofing sheets contain asbestos; some manufacturers substituted wood fibers for asbestos during the height of asbestos panic in the 1980s. Few of these products successfully penetrated the market because performance did not match that of original transite.)

Leave It In Place

Contrary to popular belief, asbestos is still legally used in many commercial applications in the U.S. today, including roofing and flooring materials; in fireproofing; and in friction products, like brake shoes and clutches. With the surge of installation of transite roofs in the 1950s and 60s, the lifespan of many of these roofs’ components is just now ending. Common factors attributing to roof or structure deterioration may include longitudinal cracks along the panel highs, broken or brittle fasteners or washers, friable panel material, and/or building shifts due to expansion or contraction. Additionally, other renovations on a building may require that old roofs that are still intact be brought up to new codes.

Today, a good general rule about asbestos is “leave it on if you can,” meaning it must be in good condition with no airborne particles.

Today, a good general rule about asbestos is “leave it on if you can,” meaning it is in good condition with no airborne particles.

Professionals encountering transite roof jobs may feel confusion about how to handle asbestos-containing materials. Some may even avoid transite jobs altogether assuming they will equate to expensive asbestos-removal procedures and red tape. However, asbestos abatement (the process of removing or minimizing asbestos health hazards from a structure) can take many forms, including removal, enclosure, encapsulation or leaving the material undisturbed.

In the past, abatement through removal was the recommendation of many asbestos professionals. Traditionally, transite was replaced with fiberglass. This solution is imperfect, however, because of the expenses of asbestos removal and new fiberglass, as well as the lower heat tolerance of fiberglass-based materials. More recently, approaches have changed and several other options present themselves.

Today, a good general rule about asbestos (and in fact the position of the Washington, D.C.-based U.S. Environmental Protection Agency) is “leave it on if you can,” meaning it must be in good condition with no airborne particles. Although not always possible, when the contractor can leave the asbestos-containing material in place, asbestos should be considered friend, not foe. Regulations might prevent installation of a new asbestos transite roof, but old buildings that can keep their transite roofs in place will continue to reap the benefits of the product’s super-strengthening properties. [Read more…]

Insulation and Roof Replacements

When existing roofs (that are part of the building’s thermal envelope) are removed and replaced and when the roof assembly includes above-deck insulation, the energy code now requires that the insulation levels comply with the requirements for new construction, according to a proposal approved by International Code Council at public comment hearings held in October 2013.

This high-performance roof system was recently installed on a high school north of Chicago. It features two layers of 3-inch 25-psi, double-coated fiberglass-faced polyisocyanurate insulation set in bead-foam adhesive at 4 inches on center, weighted with five 5-gallon pails of adhesive per 4- by 4-foot board to ensure a positive bond into the bead foam until set. PHOTO: Hutchinson Design Group LLC

This high-performance roof system was recently installed on a high school north of Chicago. It features two layers of 3-inch 25-psi, double-coated fiberglass-faced polyisocyanurate insulation set in bead-foam adhesive at 4 inches on center, weighted with five 5-gallon pails of adhesive per 4- by 4-foot board to ensure a positive bond into the bead foam until set. PHOTO: Hutchinson Design Group LLC

As a result of this proposal approval, the 2015 International Energy Conservation Code (IECC) provides new language that provides clear unambiguous direction on how the energy code provisions apply to roof repair, roof recover and roof replacement.

Until this update there was a great deal of confusion given the various terms—such as reroofing, roof repair, roof recover and roof replacement—used to describe roofing projects on existing buildings in the International Building Code and the IECC. The clarification will help to mitigate this confusion.

Numerous studies have demonstrated the energy savings provided by a well-insulated roofing system. It is critical to minimize energy losses and upgrade insulation levels when roofs are replaced to comply with code requirements for new construction.

Each year about 2.5 billion square feet of roof coverings are installed on existing buildings and the opportunity to upgrade the insulation levels on these roof systems occurs just once in several decades when the roof is replaced or even longer when existing roofs are “recovered”. Until recently this requirement was prescribed using vague and confusing language, as noted.

Moving forward the IECC will use the same definitions found in the International Building code:

  • Reroofing: The process of recovering or replacing an existing roof covering. See “Roof Recover” and “Roof Replacement”.
  • Roof Recover: The process of installing an additional roof covering over a prepared existing roof covering without removing the existing roof covering.
  • Roof Replacement: The process of removing the existing roof covering, repairing any damaged substrate and installing a new roof covering.
  • Roof Repair: Reconstruction or renewal of any part of an existing roof for the purposes of its maintenance.

A survey of building departments in many states and regions in the U.S. found that online roofing permit application forms rarely included any information on the energy code and required insulation levels. With the changes to the 2015 IECC, it will be easier for building departments to correlate the building code and energy code requirements for roof replacements.

The clarification to the 2015 IECC makes the code easier to interpret and enforce. Along the way, it will help ensure that the opportunity to save energy when replacing roofs is not lost.

Another benefit of this update is that the exemption for roof repair is now clearly defined making it easier for building owners and roofing contractors to perform routine maintenance without triggering energy-efficiency upgrades, which would add costs.