The right “team” holds your standing seam roof system together

The architect, roof manufacturer and roof construction installer are parts of a team that can work together like a well-oiled machine to get the best result – a professionally installed roof that looks beautiful and will last for decades.

I now invite you to think of your roof system as a “team” in the sense that all parts must work effectively and efficiently together like pieces of a puzzle to function optimally as designed. A well-thought-out process puts the right combination of materials together in the right way to produce an optimum roofing system.

The process requires identifying a reputable manufacturer of standing seam roofs – one that meets your specific performance and aesthetic needs, and that provides the required warranties. Once chosen, the designer may think, “Voila! Mission complete,” when in fact, the process is just beginning.

BattenLok and LokSeam

Mitchelle Elementary School features BattenLok HS and LokSeam

 

 

Since metal roofs are being used in increasingly more complicated designs, the roof panels and related accessories that attach the roof to the substructure are a part of the total roof system. The added roof curbs, pipe penetrations, crickets, snow retention devices and lightning protection equipment all become part of the standing seam roof system.  And it really matters how each of these items attach to the roof.  Though it sounds logical to do so, don’t leave it up to the roofer or another tradesperson to decide how these items will be installed.

Take control and make sure the following are adhered to when specifying a standing seam metal roof system:

Do not use dissimilar materials.

 Copper, lead and graphite can all cause galvanic corrosion. Even water dripping from these materials onto the roof can cause it to corrode. And manufacturers’ warranties are often void if this situation exists.

Some examples: Copper lightning arresting equipment is a typical use of dissimilar material found on Galvalume roots. Use aluminum instead. Lead hats are often found on Galvalume roots. Rubber jacks can be substituted.

Compile a qualified list of acceptable curb manufacturers. Choose only those that use aluminum or stainless steel. Many curb companies use Galvalume, which seems reasonable since most standing seam panels are made from this material. But when Galvalume-coated steel is welded, the Galvalume-coating melts at the weld. Even when a coating of corrosion inhibitor is used, it will never be as good as the uncontaminated Galvalume coating.

You also want a curb manufacturer that offers a weathertightness warranty if required for the roof. Roof manufacturers will generally warrant the attachment of the roof curb to their roof panels, but it’s up to the roof curb manufacturer to warrant the construction and performance of their product.

Be careful with roof curbs.  First off, they should be “shingled” into the roof. This way, all laps shed water as it drains from the roof. Curbs that lap on top of the roof panels on the upslope side will cause problems.

Roof curbs must allow plenty of room for water to drain around them without building up a waterhead at the upslope end.  Provide clearance on both sides of the curb and a long flange on the upslope end so the roof panels can lap onto the flange and maintain a 12” upslope from the top of the water diverter built into the curb.

Finally, if AC units will be placed on the roof, include PVC condensate lines to carry the water off of the roof. Never allow the condensate to drain directly onto the roof. The dissolved copper ions which will cause galvanic corrosion of the roof panels.

This is a lot to consider, possibly more than you thought was involved. Well friends, there’s even more. I’ll explore this even further in my next post.

In the meantime, learn more about MBCI’s rigorously-tested, standing seam metal roof systems and how it’s one of the most durable and weathertight roof systems available in the industry. Find out more.

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Air barriers and vapor retarders

Air Barrier Vapor Retarders

Building design and code requirements are readily becoming rooted in building science, which is the study of heat, air, and moisture movement across the building envelope.

Reducing the heat energy transfer (which is bi-directional based on geography and climate) is why insulation is used.  And arguably more important is the need to reduce airflow (aka, air leakage) across and through building envelopes.  This airflow often includes a lot of heat and moisture; therefore, buildings’ HVAC systems work hard (and use energy…and cost money) to make up for the heat and moisture gains and losses in order to maintain proper interior temperature and humidity levels.  Environmental Building News, in an article titled The Hidden Science of High-Performance Building Assemblies (Nov. 2012) , stated “Air infiltration and exfiltration make up 25%-40% of total heat loss in a building in a cold climate and 10%-15% of total heat gain in a hot climate.”  This is why the model codes are now mandating air barriers.

The 2012 International Energy Conservation Code (IECC), Section C402.4, Air leakage (Mandatory) provides the requirements for air barriers in new construction.  Prior to 2012, building codes did not include air barrier requirements.  The first step taken in the IECC was to mandate air barriers in Climate zones 4, 5, 6, 7, and 8 (locations north of the Mason-Dixon Line, in a broad sense).  Climate zones 4 through 8 are heating climates, where the largest potential for heat loss occurs.   The IECC provides three ways to comply; air barriers requirements can be met through material, assembly, or whole building testing.  A blower door test, used to test a whole building, seems to be the most common way used to show code compliance currently.  The IECC included a list of materials that prescriptively meet the code requirements for air barrier materials; sheet steel and aluminum are on that list.

Three years later the 2015 IECC went a step further.  Section C402.5, Air leakage—thermal envelope (Mandatory) extended the requirement for air barriers by mandating their use in all climate zones in the United States except zone 2B, which is a hot/dry zone.  Climate zone 2-dry includes only southwest Arizona, southwest Texas, and a small part of Southern California.  Essentially all new buildings in the United States are required to have air barriers, and sheet steel and aluminum remain prescriptive air barriers.  It’s important to know that when reroofing, the air barrier requirements do not apply.

The IECC is available for purchase on ICC’s website:  www.iccsafe.org.

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MBCI welcomes Insurance Institute of Building and Home Safety to witness in-house testing

To ensure our products perform as expected, MBCI conducts a variety of tests at our onsite laboratory in Houston, Texas. On April 16, MBCI and our parent company, NCI Building Systems, welcomed several researchers from the Insurance Institute of Building and Home Safety (IBHS) to our Houston headquarters to witness ASTM E1592 testing on MBCI’s standing seam roof panel Double-Lok. This test is designed to evaluate the structural performance of a standing seam roof system under uplift loading experienced by roofs during wind events.IBHS, NCI and MBCI at MBCI Testing Facility

IBHS conducts research to improve loss prevention-related design practices and better understand the risks of insuring buildings and homes.  IBHS’s facilities include a full-scale wind tunnel in South Carolina which recently tested a 30’ wide, 50’ long building by our sister company, Ceco Building Systems, using the same standing seam roof system used in the E 1592 test.  IBHS’s researchers joined our testing to observe how manufacturers test their own products so they may develop design-related loss prevention strategies which can help reduce insurance costs for consumers of metal roofing.

NCI’s Senior Research and Development Engineer Mark Detwiler, who was present at the testing, said “[IBHS] indicated that the test they witnessed reinforced that the industry rigorously tests their roof systems. They also noted that the failure mode they witnessed was consistent with what they have seen in their loss investigations, meaning that the test yields realistic, predictable results.”

Learn more about Double-Lok, ASTM E1592 testing and IBHS and their research efforts.

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When it comes to roofing expertise, it doesn’t hurt to diversify

As is often the case when it comes to your investments, it’s always a good idea to diversify. This also applies to the investment of your construction expertise as a roofing contractor. Even with the mild uptick in new construction activity of late, contractors are smart to explore the additional revenue stream that can come from roof renovations and retrofits.

Example of Retrofit Metal Panel, NuRoofMost metal roof retrofit work entails adding slope to an existing flat- or low-sloped roof.  According to a 2013 article in Metal Construction News, about 25 percent of U.S. commercial, institutional and public buildings are 55 years old or older and consist of flat-roof stock that has reached the end of its service life. Two years later, that percentage is surely higher.

To transition from a flat roof to a sloped roof is a good move, because it will result in lower energy and maintenance costs for years to come.  It is also environmentally smart, because metal is one of the most recycled materials used in construction, and metal roofing is 100 percent recyclable at the end of its service life. A metal roofing system provides for additional insulation, as well as the installation of solar panels that reduce reliance on electricity. And in most circumstances, a new metal roof can be installed without having to remove the existing flat roof. A metal retrofit may carry a higher initial cost, but when total life-cycle cost is considered, a metal retrofit will end up being the lowest cost alternative.

A large number of buildings with flat membrane or built-up roofs require a framing system to produce an adequate slope. But this particular type of retrofit can be challenging. In general, the retrofit market is more specialized and much more technical than what roofing contractors are likely used to in the existing metal building market. At the same time, the retrofit market can be very profitable and is worth getting up to speed on.

Whether you’re doing a small retrofit project or a complete renovation, MBCI can assist you with developing a preliminary budget, estimating, engineering, as well as providing a complete set of shop drawings for your retrofit project.

Stay tuned for future posts where we’ll provide some guidelines on how to successfully navigate the design process of retrofitting a flat or inadequately sloped built-up or membrane roof.  Adding this diversity to your portfolio of roofing skills will likely net a high return on investment.

Learn more about retrofit solutions.

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Part II – Transparency in building products

Transparency in Building Products

A huge buzzword in the building products industry these days is transparency.  The green building movement, which has previously focused on high-performing buildings with a strong emphasis on energy efficiency and fossil fuel use reduction, has increasingly put its cross hairs on occupant exposure risk in the last few years.  Although that change alone is probably enough to start some controversy, how this new emphasis is being implemented is really fueling the fire for new arguments.  If you read our last blog, Part I – The importance of consensus in building standards,  then you should be familiar with how building codes are developed in a consensus-based forum in which all affected parties have some say.  However, many of the movers and shakers of the green building movement have bypassed that forum by folding the requirements they want to emphasize into voluntary programs of their own creation.  At the same time, they lobby owners and building officials to carry some level of compliance to these programs, offering a benefit of being able to say their buildings or communities are “green” by displaying plaques on the façade or being listed on a website.

Although that tact seems fair on the surface, it really puts a lot of power into the hands of self-proclaimed experts to decide on the definition of “green” they want to use for their program. As we discussed in Part I, the ANSI consensus process requires policy-making organizations to transparently prove their competence in subjects they affect with their policy.  Furthermore, they also have to publicly announce the formation of a committee (called a “Call for Committee”) they designate to create and maintain this policy.  They must also allow members of the public to submit curricula vitae for consideration to join the committee without necessarily being a member of the organization.  This introduces a mechanism to balance the power the committee is usurping by having control of the policy going forward.  Unfortunately, no such mechanism exists for many of the authors of voluntary green building programs and the negative aspects of this are particularly pronounced in the area of building product transparency.

One of the most common ways green building programs administer transparency is through the use of a “red list,” which is essentially a list of banned substances.  Using California Proposition 65 or Europe’s RoHS as a model, many of the NGO-based programs related to buildings have some type of requirement that aims to reduce or eliminate the use of ingredients that could possibly be harmful to building occupants.  In many instances, these same NGOs offer third-party listing programs that a building manufacturer can join and have their products declared as meeting the requirements.  Many people see this as a conflict of interest since an NGO, typically funded through donations, is in a position to act as a gatekeeper, allowing in only those companies or industries that support the NGO financially or align themselves with the NGO’s agenda.

But there is a deeper, more disturbing aspect:  Although the list itself may start out as a publicly accepted and scientifically based enumeration of toxic ingredients, NGOs often add other substances that are not known, or in some cases, even suspected, to be toxic in order to dissuade architects from specifying certain products or deploying certain construction methods.  Quite often, the NGO will develop the red list in closed discussion forums where manufacturers have no ability to provide evidence to substantiate that their products are indeed safe.  At best, a manufacturer can ask the NGO to consider exceptions or modifications.  But ultimately, a manufacturer has no assurance that their case has been adequately considered because they are not allowed to attend the forum.  Sadly, this is what passes for transparency in green construction more often than not lately.

This lack of due process came to a head in 2013, when members of congress began to express concern that LEED, the green building program used by the military and the General Services Administration, was not an ANSI-based standard.  In response, the GSA formally announced that they would take public comment on the subject and decided nine months later that they would continue to specify LEED but other ANSI-based programs would be considered going forward as well.  Meanwhile, the military announced that they were developing their own standard, distancing themselves from LEED.  This quelled the discussion for a while and allowed other, even hotter subjects like healthcare to take the spotlight.  But concern lives on that the lack of transparency in the development of LEED and similar programs is leading the public down a dangerous, politics-as-usual road.

However, the news is not all bad.  There are several organizations that use an ANSI-based process to develop and maintain their programs so that the requirements can readily be incorporated into public policy.  ASHRAE, ICC, and a newcomer in the U.S., The Green Building Initiative, have all invested the tremendous amount of time and effort it takes to develop their standards in an ANSI-based public forum, and their respective programs offer a building owner or code official a great alternative to vague voluntary programs subject to interpretation by self-proclaimed experts.  We will explore several of those options in our next blog.

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Metal walls and panels a big plus when it comes to Net Zero Energy

Kickapoo Tribe Government & Community Building

Kickapoo Tribe Government & Community Building features MBCI’s eco-FICIENT Grand H and Grand V

Are you familiar with “Net Zero Energy?” No, it’s not that sense of power you got from using that early dial-up Internet browser of the 1990’s (The company, by the way, is still in existence, and comes up in searches for the term Net Zero. Who knew?). The Net Zero Energy I’m speaking of is the enviable, sustainable state achieved when the creation and use of energy within the same building system are equal.

Though achievable, the cost and capacity for producing energy within a building system is greater than that of creating energy efficiency in one. The good news is that metal roofing and wall panels are extremely useful on both sides of the equation.

On the energy efficiency side, insulated metal panels (IMPs) provide roof and wall systems with the thermal and radiative performance needed for sustainable design. eco-FICIENT® insulated wall and roof panels provide continuous insulation and eliminate thermal bridges. As building and energy codes become increasingly more stringent, insulated metal panels are an ideal choice for thermally efficient building envelopes.

Davidson Center for Space Exploration

Davidson Center for Space Exploration features MBCI’s eco-FICIENT Royal and Insulated BattenLok

On the other side of the equation, a common method of generating energy is through the use of photovoltaics (PVs), and metal roofs provide the best possible surface to host a photovoltaic (PV) array. Solar photovoltaic systems and solar water heating systems can be installed on a metal roof, penetration-free, resulting in high performance with minimal risk. Both the use of IMPs and the installation of PVs on metal roofs can be used with proper designs to maximize building energy efficiency.

Of course, metal roofing, known to last 40 years or longer, is the only type of roof that can be expected to outlive the PV system mounted on it, which results in virtually zero maintenance and a very low in-place cost for the roof and PV system together.  A sustainability win, a durability win, and, of course, an aesthetic win.  The result is anything but a zero sum game.

Find out more about MBCI’s eco-FICIENT®  IMPS

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Lightning can be a lucky strike with Metal Roofs

LightningArticleBuilding owners and managers fortunate enough to have a metal roof know personally its durability, resiliency and reliability, not unlike that contributed to the U.S. Postal Service of yore:  “Neither snow nor rain nor heat nor gloom of night …”—nor fire, nor hail nor the like—will prevent it from fulfilling its function. Those natural elements conspire to knock on the good reputation of a metal roof, to no avail. But how does a metal roof hold up against a more ominous threat… lightning?

Metal conducts electricity, so it’s not unreasonable to have concerns about whether a metal roof is the best material with which to build a roof to avoid damage from lightning.

According to the Metal Construction Association’s technical bulletin on Lightning and Metal Roofing, the probability of a lightning strike is determined by a several factors:

  1. Topography in the area of the structure: The probability of a strike is higher if a structure is situated on a mountaintop or hilltop as opposed to a field.
  2. Size and height of the subject structure. A tall building or a facility covering a large ground area is more likely to be struck than a short or small building. A tall, thin structure, such as a tower, a tree or utility pole, is also a more likely target for a lightning strike.
  3. Relative location of the structure with respect to nearby larger and taller structures. A very tall structure located near a small, short one will tend to further reduce the likelihood of a strike to the smaller one.
  4. Frequency and severity of thunderstorm activity in the geographic area of the project.

Notice there is no mention of the material from which the structure is made. In fact, the probabilities of a strike to a metal roofed structure are no more or less than any other kind of structure. The probably risk has more to do with the height and size of the structure and its surroundings than the material of which it is made.

The use of a lightning protection system, such as lightning rods, may lessen the consequence of a strike. And if lightning does strike a building, a metal roof actually can cause the energy impact to disperse evenly and uneventfully through the structure. Finally, metal roofing isn’t combustible or flammable.

Bottom line, metal is probably the best material option for roofing, and a safer source of protection for your facility , customers and employees when the inevitable storms come.

Find out more about MBCI Roofing products

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Part 1 – The importance of consensus in building standards

Building Code Standards BlogMost people understand the purpose of a building code: To ensure the safety of the occupants and to establish the minimum accepted performance level of the building and its systems.  Fewer people understand that because building codes are adopted into law by a governing body, technically referred to as an Authority Having Jurisdiction or AHJ, they are an in fact an extension of the law or ordinance that brings them into effect.  Knowing that, you should not be surprised to learn that like laws, building codes in America can’t just be arbitrarily made up by somebody having the authority and know-how to do so.  Instead, they must have gone through some type of consensus process in which all affected entities or their representatives have the opportunity to participate. This concept, called Due Process of Law, is central to many governmental charters such as the Magna Carta and The Constitution of the United States of America and is designed to ensure that a person’s individual rights are not unfairly taken away.

Under the US Constitution, laws are written by Congress and interpreted by judges.  Members of Congress are elected by their constituents and judges are either appointed by elected officials or elected themselves.  Similarly, building codes are written by consensus bodies, like the International Code Council or ICC, and interpreted by Building Officials, who are generally appointed by elected officials.  The code development process used by ICC is one where any interested member of the public can participate and is guaranteed a forum to propose changes and comment on the proposed changes submitted by others using a system governed by Roberts Rules of Order.  After discussion and debate, the code committee votes on the individual proposals and those that pass are incorporated into the code, guaranteeing due process.  (Actually, it’s quite a bit more complicated than this but for purposes of this blog, let’s just leave it at that.)

However, building codes commonly do not actually spell out all of the requirements for buildings and building systems.  More and more, the code will delegate low-level detailed requirements to a different type of document called a standard, and then brings the requirements contained within by referencing the standard in the code by name.  Likewise, these standards then must also be developed through a consensus process administered by an adequate standard development body.  But because all standard development bodies are structured a little differently, it is not realistic to mandate that consensus process directly.  Instead, another independent body called The American National Standards Institute or ANSI, certifies standard development bodies as having a sufficient consensus processes to be deemed as meeting the incorporating code requirements for due process.  Examples of these bodies are the American Society of Civil Engineers (ASCE) who develop ASCE 7, the document that determines the minimum load requirements for buildings; the American Society of Testing and Materials (ASTM) a group widely known for developing material and testing specifications for general use; and the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE), who develops ASHRAE 90.1, the document that spells out the minimum building energy efficiency requirements.  If you are an architect or engineer, all of these acronyms should sound very familiar to you.

Another acronym that you are probably familiar with is LEED, which stands for Leadership in Energy and Environmental Design.  It is developed and maintained by the US Green Building Council (USGBC) and is the premier green building program in the world.  Interestingly though, the development landscape changes drastically when it comes to green construction programs like LEED.  You see, the USGBC is not an ANSI accredited standard developer and thus LEED is not an actual official standard, hence the use of the word “program”.  How then is it possible that USGBC can have so much say in how buildings, particularly publicly owned buildings, get built?  The answer is that they get around this limitation by structuring LEED as a voluntary program and then lobbying the potential owners of buildings, like the US and state governments, into using their program by executive order rather than legislating the requirement directly.  If you’ve watched TV at all in the last year, particularly with respect to immigration reform, you know how controversial this approach can be.  Nevertheless, it is perfectly legal in this context.

This really has not been a significant issue to date because LEED does have a consensus process (albeit not an ANSI accredited one) and LEED credit requirements have been fairly uncontroversial in past versions.  However, LEED v4, the latest generation of the wildly popular green building program, changed all of that by adding credits that are less about design and functionality of the building and more about transparency with respect to building product ingredients to ensure occupant health and comfort.  Let’s be clear: Most reasonable people, including building product manufacturers, don’t have a problem with increased transparency and want more occupant comfort and health.  But it is how LEED defines “transparency” in version 4 has many people up in arms and they point to the hypocrisy of developing a definition to the word “transparency” during a closed-door meeting with no manufacturers at the table as what is wrong with green building as it exists today.  My next blog will explore that concept further.

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The art of properly specifying snow retention systems

The recent arctic blasts that hit the northeast brought to mind many things: hot cocoa, the evils of shoveling snow, a nice fire, the longing for a warm beach and, of course, how to properly specify snow retention systems on standing seam roofs. I’m not alone here, right?

All jokes aside, when I was scratching my brain for a new blog post, the cold weather and blizzards reminded me how easy it is to specify snow retention devices improperly. It might appear rather elementary at first; you might think it is as simple as planning for snow retention around entrances and frequent walkways. If so, you, along with many others, are mistaken. Let’s review some not-so-obvious areas to consider while planning a snow retention system for a SSR.

Gutters If a gutter is used that has a face high than the pan of the roof panels, the gutter must be protected from sliding ice and snow. Gutters are designed for one purpose – to channel the water to a downspout. If it is left unprotected it cannot resist sliding ice and snow.

Pipe penetrations As ice and snow slides down a roof and encounters a pipe penetration, the force can cause the pipe to move down slope and damage the roof jack and the roof, or shear the pipe at the roof surface.

Upper roofs draining into lower roofs The upper roof should have a snow retention system installed to prevent ice and snow from falling onto the roof below. Without snow retention, the sliding ice and snow can cause extensive damage to the roof membrane and to equipment on the lower roof.

Panel seams perpendicular to the main roof slope Connector roofs or dormers are typical examples of this type of roof area. The main roof slope provides a surface for ice and snow to slide toward the eave. If it then encounters a roof surface that is perpendicular to this main slope, damage to the roof panels and trim on these roof areas can occur.

Valleys in high snow load areas Valleys allow for snow to slide down a surface that is perpendicular to the panel seams. This offers the potential to bend panel seams down or shear them from the panel.

Aside from considering these areas while planning your snow retention system, also use clamps instead of screws to attach the system to the standing seams of the roof panels. Screws not only perforate roof panels but can also pin the roof and prevent it from floating as designed. Clamps, by comparison, have been tested and can be engineered for the specific roof to which they will be attached, allowing for the snow load, roof slope, panel run length and other details. These clamps do not penetrate the roof membrane, do not hinder roof expansion and are easily installed with a screw gun.

Lastly, I recommend having a registered, professional engineer design a retention system that meets the specified snow loads for the project. Without their expertise there are possible repercussions. If the snow retention system cannot support the snow load, it can result in an entire system failure and major roof damage. This could potentially cause snow and ice to fall and hurt bystanders.

By keeping all of these in mind, along with proper installation and maintenance, a snow retention system will help your SSR survive winter blasts and protect pedestrians, too.

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Standing the test of time: new study reveals 55% Al-Zn alloy coated standing seam roofs last 60 years

The majority knows that metal roofs are durable, but it wasn’t until recently that a study showed the longevity of low-slope unpainted 55% Al-Zn alloy coated steel standing seam roofing (SSR) systems- 60 years. With the service life of a commercial building being 60 years, according to LEED version 4, this means that essentially the metal roof system described above, and commonly referred to as Galvalume® metal roofs, does not require replacement. To put this into context, by comparison most non-metal roofs require at least one replacement during the same period. This study also reveals that the longevity of a 55% Al-Zn alloy coated standing seam roofing system far surpasses the typical warranty period granted, which is 25 years. Basically, this is a game changer and we, manufacturers, are thrilled!

Technical Director of MCA Scott Kriner said, “This study is a breakthrough for the metal construction industry because it finally provides third-party, scientific data that backs up the long held stance that 55% Al-Zn coated steel standing seam roofing systems are very durable, economic and can be better for the environment.”

Let’s take a closer look at the study. The Metal Construction Association (MCA) and Zinc Aluminum Coaters (ZAC) Association sponsored it. The study involved three independent consulting firms testing 14 buildings in five climate zones. The variety of structures and climates allowed them to analyze how Galvalume metal roofs perform in a range of temperatures, humidity and precipitation pH, or acidity, levels. All of these can affect the metallic corrosion rate of roof panels, their sealants and components, and that’s what the consulting firms analyzed.

Here were some of their findings:

  • First, the sealant life is the primary deciding factor in establishing end-of-life for Galvalume metal roof systems. In certain structures analyzed that were 35 years old, the sealant was considered “entirely adequate and without issue.” Based on the sealant performance, the study conservatively projected the lifespan of such roof systems to be 60 years.
  • Secondly, although a Galvalume metal roof is moderately maintenance-free, all roof systems require a periodic inspections and maintenance in order to achieve such long lifespans.
  • Thirdly, while the roof system as a whole was projected to last up to 60 years, components may need to be replaced during this period. The cost of replacing components, however, is considerably less than 20% of replacing an entire roofing system, which is the value deemed by this study as excessive to the point of constituting the end of service life for a roof system.
  • Lastly, the study unveiled that even on areas typically most susceptible to corrosion, such as panel profile bends, there was an absence of significant rust after 35 years; even at its most vulnerable areas, a Galvalume metal roof system performs well.

So what does it mean for architects and building owners? Speaking from a purely biased manufacturer’s prospective, specify and purchase more metal roofs! All jokes aside, this study displays the appeal in selecting a metal roof because it reduces the maintenance costs of the building. It also changes and increases the accuracy of Life Cycle Cost (LCC) or whole building Life Cycle Assessment (LCA) associated with Galvalume metal roof systems by providing tangible research as opposed to previous calculations based on roofing professionals’ opinions. To find out more information or to download the full report, visit http://www.metalconstruction.org/index.php/education/technical-resources.

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