Minimizing Disruption When Repairing Roofs on Schools and Hospitals

Have you ever thought about building products reducing the carbon dioxide emissions caused by your building? When considered over their useful life, materials like insulation decrease total carbon emissions thanks to their performance benefits. Read on for an explanation of how this can work in your designs.What is Total Carbon?Total carbon captures the idea that the carbon impacts of buildings should be considered holistically across the building's entire life span and sometimes beyond. (In this context, "carbon" is shorthand for carbon dioxide (CO2) emissions.) Put simply, total carbon is calculated by adding a building's embodied carbon to its operational carbon.Total Carbon = Embodied Carbon + Operational CarbonWhat is Embodied Carbon?Embodied carbon is comprised of CO2 emissions from everything other than the operations phase of the building. This includes raw material supply, manufacturing, construction/installation, maintenance and repair, deconstruction/demolition, waste processing/disposal of building materials, and transport between each stage and the next. These embodied carbon phases are indicated by the gray CO2 clouds over the different sections of the life cycle in the image below.We often focus on "cradle-to-gate" embodied carbon because this is the simplest to calculate. "Cradle-to-gate" is the sum of carbon emissions from the energy consumed directly or indirectly to produce the construction materials used in a building. The "cradle to gate" approach neglects the remainder of the embodied carbon captured in the broader "cradle to grave" assessment, a more comprehensive view of a building's embodied carbon footprint.What is Operational Carbon?Operational carbon, on the other hand, is generated by energy used during a building's occupancy stage, by heating, cooling, and lighting systems; equipment and appliances; and other critical functions. This is the red CO2 cloud in the life-cycle graphic. It is larger than the gray CO2 clouds because, in most buildings, operational carbon is the largest contributor to total carbon.What is Carbon Dioxide Equivalent (CO2e)?Often, you will see the term CO2e used. According to the US Environmental Protection Agency (EPA), "CO2e is simply the combination of the pollutants that contribute to climate change adjusted using their global warming potential." In other words, it is a way to translate the effect of pollutants (e.g. methane, nitrous oxide) into the equivalent volume of CO2 that would have the same effect on the atmosphere.Today and the FutureToday, carbon from building operations (72%) is a much larger challenge than that from construction materials' embodied carbon (28%) (Architecture 2030, 2019). Projections into 2050 anticipate the operations/embodied carbon split will be closer to 50/50, but this hinges on building designs and renovations between now and 2050 making progress on improving building operations.Why Insulation?Insulation, and specifically continuous insulation on low-slope roofs, is especially relevant to the carbon discussion because, according to the Embodied Carbon 101: Envelope presentation by the Boston Society for Architecture: Insulation occupies the unique position at the intersection of embodied and operational carbon emissions for a building. Insulation is the only building material that directly offsets operational emissions. It can be said to pay back its embodied carbon debt with avoided emissions during the building's lifetime.A Thought Experiment on Reducing Total CarbonTo make progress on reducing the total carbon impact of buildings, it is best to start with the largest piece of today's pie, operational carbon. Within the range of choices made during building design and construction, not all selections have the same effect on operational carbon.When making decisions about carbon and energy reduction strategies, think about the problem as an "investment" rather than a "discretionary expense." Discretionary expenses are easier to reduce or eliminate by simply consuming less. In the example below, imagine you are flying to visit your client's building. Consider this a "discretionary expense." The input on the far left is a given number of kilograms of carbon dioxide equivalent (CO2e) generated for the flight, from the manufacturing of the airplane, to the fuel it burns, to its maintenance. The output is the flight itself, which creates CO2 emissions, but no durable good. In this case, the only CO2 reduction strategy you can make is to make fewer or shorter flights, perhaps by consolidating visits, employing a local designer of record, or visiting the building virtually whenever possible. Now consider the wallpaper you might specify for your client's building. It involves a discretionary expenditure of CO2e, in this case, used to produce a durable good. However, this durable good is a product without use-phase benefits. In other words, it cannot help to save energy during the operational phase of the building. It has other aesthetic and durability benefits, but no operational benefits to offset the CO2 emissions generated to create it. Your choices here are expanded over the previous example of an airplane flight. You can limit CO2 by choosing a product with a long useful life. You can also apply the three Rs: reduce the quantity of new product used, reuse existing material when possible, and recycle product scraps at installation and the rest at the end of its lifespan. In the final step in our thought experiment, consider the insulation in your client's building. As before, we must generate a certain amount of CO2e to create a durable good. In this case, it's one with use-phase benefits. Insulation can reduce operational energy by reducing heat flow through the building enclosure, reducing the need to burn fuel or use electricity to heat and cool the building. The good news is that, in addition to the other strategies considered for the flight and the wallpaper, here you can also maximize operational carbon savings to offset the initial embodied carbon input. And, unlike the discretionary nature of some flights and the often optional decision to use furnishings like wallpaper, heating and cooling are necessary for the functioning of almost all occupied buildings.Based on this example, you can consider building products with operational benefits, like insulation, as an "investment." It is appropriate to look at improving the building enclosure and understanding what the return on the investment is from a carbon perspective. As the comparison above demonstrates, if you have a limited supply of carbon to "invest", putting it into more roof insulation is a very smart move compared to "spending" it on a discretionary flight or on a product without use-phase carbon benefits, such as wallpaper.This means we should be careful not to measure products like insulation that save CO2e in the building use-phase savings only by their embodied carbon use, but by their total carbon profile. So, how do we calculate this?Putting It to the TestWe were curious to know just how much operational carbon roof insulation could save relative to the initial investment of embodied carbon required to include it in a building. To understand this, we modeled the US Department of Energy's (DOE) Standalone Retail Prototype Building located in Climate Zone 4A to comply with ASHRAE 90.1-2019 energy requirements. We took the insulation product's embodied energy and carbon data from the Polyisocyanurate Insulation Manufacturers Association's (PIMA) industry-wide environmental product declaration (EPD).To significantly reduce operational carbon, the largest carbon challenge facing buildings today, the returns on the investment of our building design strategies need to be consistent over time. This is where passive design strategies like building enclosure improvements really shine. They have much longer service lives than, for example, finish materials, leading to sustained returns.Specifically, we looked here at how our example building's roof insulation impacted both embodied and operational carbon and energy use. To do this, we calculated the cumulative carbon savings over the 75-year life of our model building. In our example, we assumed R-30 insulation installed at the outset, increased every 20 years by R-10, when the roof membrane is periodically replaced.In our analysis, the embodied CO2e associated with installing R-30 (shown by the brown curve in years -1 to 1), the embodied carbon of the additional R-10 of insulation added every 20 years (too small to show up in the graph), and the embodied carbon represented by end-of-life disposal (also too small to show up) are all taken into account. About five months after the building becomes operational, the embodied carbon investment of the roof insulation is dwarfed by the operational savings it provides. The initial and supplemental roof insulation ultimately saves a net of 705 metric tons of carbon over the life of the building.If you want to see more examples like the one above, check out PIMA's study, conducted by the consulting firm ICF. The research group looked at several DOE building prototypes across a range of climate zones, calculating how much carbon, energy, and money can be saved when roof insulation is upgraded from an existing baseline to current code compliance. Their results can be found here. Justin Koscher of PIMA also highlighted these savings, conveniently sorted by climate zone and building type, here.Support for Carbon Investment DecisionsSo how can you make sure you address both operational and embodied carbon when making "carbon investment" decisions? We've prepared a handy chart to help.First, when looking at lower-embodied-carbon substitutions for higher-embodied-carbon building materials or systems (moving from the upper-left red quadrant to the lower-left yellow quadrant in the chart), ensure that the alternatives you are considering have equivalent performance attributes in terms of resilience and longevity. If an alternative material or system has lower initial embodied carbon, but doesn't perform as well or last as long as the specified product, then it may not be a good carbon investment. Another consideration here is whether or not the embodied carbon of the alternative is released as emissions (i.e. as part of its raw material supply or manufacturing, or "cradle to gate" stages), or if it remains in the product throughout its useful life. In other words, can the alternative item be considered a carbon sink? If so, using it may be a good strategy.Next, determine if the alternative product or system can provide operational carbon savings, even if it has high embodied energy (upper-right yellow quadrant). If the alternative has positive operational carbon impacts over a long period, don't sacrifice operational carbon savings for the sake of avoiding an initial embodied product carbon investment when justified for strategic reasons.Last, if a product has high operational carbon savings and relatively low embodied carbon (lower-right green quadrant), include more of this product in your designs. The polyiso roof insulation in our example above fits into this category. You can utilize these carbon savings to offset the carbon use in other areas of the design, like aesthetic finishes, where the decision to use the product may be discretionary but desired.When designing buildings, we need to consider the whole picture, looking at building products' embodied carbon as a potential investment yielding improved operational and performance outcomes. Our design choices and product selection can have a significant impact on total carbon targets for the buildings we envision, build, and operate.Click these links to learn more about GAF's and Siplast's insulation solutions. Please also visit our design professional and architect resources page for guide specifications, details, innovative green building materials, continuing education, and expert guidance.We presented the findings in this blog in a presentation called "Carbon and Energy Impacts of Roof Insulation: The Whole[-Life] Story" given at the BEST6 Conference on March 19, 2024 in Austin, Texas.References:Architecture 2030. (2019). New Buildings: Embodied Carbon. https://web.archive.org/web/20190801031738/https://architecture2030.org/new-buildings-embodied/ Carbon Leadership Forum. (2023, April 2). 1 - Embodied Carbon 101. https://carbonleadershipforum.org/embodied-carbon-101/

A low-slope commercial roofing system is responsible for keeping the elements out of the building. During heavy rain, water with nowhere else to go may pond on the roof. A roof drain prevents water from ponding by providing a way for it to leave the roof, and regular commercial drain maintenance ensures its continued performance.Although commercial buildings may appear to have flat roofs, some roofs have slopes built into the structure or require added slopes, typically achieved with tapered insulation to facilitate water drainage. This slope is designed to guide water to a drain, so it doesn't sit on the roof and damage the roofing system or structure. Standing water can slowly deteriorate certain roofing materials and cause premature degradation, failure, or damage. It can also promote algae and plant growth and attract nuisances such as birds and insects.Guiding Water off the RoofResidential roofs have gravity on their side—water flows down the slopes into gutters that transport it away from the home. Commercial buildings with low-slope roofs have to work a little harder to remove water, which is where roof drains come into play.The roofing system design can help guide water toward the drains. It often involves using tapered insulation such as GAF EnergyGuard™ tapered polyiso insulation. The two most popular tapered boards deliver a 1/8-inch or 1/4-inch per foot slope. This slight slope prevents water from standing on the roof, forcing it toward a drain strategically installed at various low points on the roof with crickets and saddles.Drain placement is particularly essential when the parapet wall sheds water. To help water arrive at the drain line or gutter, tapered crickets are typically installed in corners and between drains to direct the flow and alleviate ponding. This water must flow down the roof side of the parapet wall and follow the roof slope to reach the drain.3 Common Types of Roof DrainsInner DrainsInner drains are connected to sloped pipes under the roof that carry water off the roof and away from the building. They typically rely on gravity and the roof's slope to get water to the drain.ScuppersScuppers are found at the roof's edge, usually installed through a hole in the parapet wall. They're designed to drain water from the roof into a downspout or may extend out from the building to shed water.Siphonic DrainsSiphonic drains feature a baffle that keeps air out and allows water to fill the pipes. Once the pipes are full, the lack of air creates a vacuum that siphons water from the roof at a high velocity. The baffle also keeps leaves and debris from gathering in the drain and causing a blockage.Caring for and Maintaining Roof DrainsInspecting and maintaining roof drains should be part of your regular roof inspections. Because roof drains are located at low points on the roof, it's easy for debris or leaves to build up in these areas. Clearing debris is essential for the drains to function properly. Clogs encourage pools of water to form on the rooftop, which can cause structural issues for the building. Even just an inch of standing water can add thousands of pounds of weight to the roof, reinforcing the need for regular commercial drain maintenance.Advancing Roof Drain Maintenance with TechnologyGAF recently introduced the Steely Drain™. This is a roof drain solution that leverages technology allowing contractors to build their maintenace relationship by setting up building maintenance reminders to contact building owners or facility managers. This contractor-inspired drain is made of 316L marine-grade stainless steel, making it ideal for tough environments that require exceptional corrosion resistance.Steely Drain™ features a QR code etched onto the top that you can scan with your smartphone to instantly view information about the roofing system. This data can include the contact information of the contractor who installed the system, the architect and consultants for the project, and the roofing system details if all information is inputted.This critical data is managed from a convenient GAF-hosted dashboard and plays an important role in the roof's maintenance plan. Contractors can set up and receive email reminders when it's time to perform scheduled roof and drain inspections. The dashboard also eliminates the need for core cuts since every detail of the roofing system is available through the QR code—from the deck type to the cover board, underlayment, insulation type and thickness, to the final membrane.Knowledge Is Key to SuccessWhen properly installed and maintained, roof drains can keep the rooftop free of standing water for many years. Curious to learn more? Explore how the Steely Drain™ can help you with your ongoing maintenance programs. You can also visit the GAF CARE Contractor Training Center to gain additional tips and access valuable training courses that allow you to learn at your own pace.

With the growing popularity and versatility of PVC roofing systems, GAF has responded by building a team of PVC experts to aid architects, specifiers, and the design community in project success. These highly trained and experienced professionals offer 1:1 support to help answer customers' questions and unique needs when working with PVC on roofing projects, and are here to help you!PVC, or polyvinyl chloride, is a single-ply thermoplastic roofing membrane. The material's characteristics help it thrive in particularly challenging applications. In fact, PVC roofing systems have a proven track record in the US, first introduced in the 1970s after making their debut in Germany a decade earlier.Here's a look at the benefits of PVC roofing systems as well as the guidance and support offered by the PVC experts at GAF.PVC Roofing Advantages and ApplicationsWhile several materials are available for use in roofing systems, PVC has been identified as a particularly long-lasting option. Accordingly, it's steadily grown in popularity nationwide.David Allor, senior area PVC specialist, joined the GAF team in 2022 as a PVC expert. His role was created specifically to support roof designers. Allor has an extensive background in the commercial roofing industry and extensive knowledge about PVC as a high-performance roofing solution."The industry refers to it as a very spec-driven product, and I believe what they're speaking to is a specifier's preference to work with a product that's been well established in the market and field tested," Allor shares. "It has the ability to provide protection against chemical exposure* and stand up well to challenging environments."While PVC may be a spec-driven product, it's also application-driven. Allor explains that PVC roofs may help provide protection for restaurants, food manufacturers, and packaging plants—any facility using animal fats where oils may be exhausted.* He also says that even if the building itself isn't exhausting gases, grease, or chemicals, it's important to consider the buildings and structures that surround it, as their exteriors may be subjected to exhaust that could degrade roofing systems.*Supporting the Design CommunityAs North America's largest roofing materials manufacturer, GAF has equipped teams with the resources and specialists needed to supply customers with more than just products. In recent years, the company built a solid team of PVC specialists that cover the entire US. These specialists assist customers with PVC specifications, roof system designs, and whatever else designers need to ensure successful project outcomes.Whether your project or design firm is based in the Northeast, Southeast, Southwest, Midwest, or West Coast, a PVC specialist is positioned to help. Allor explains the team of GAF PVC specialists is active in the organizations specifiers belong to, including the American Institute of Architects, the Construction Specifications Institute, and the International Institute of Building Enclosure Consultants.Allor describes the team's role as supporting the customer and connecting them to other GAF project support teams that can help. For instance, he said he called on a leading architectural design firm in the Boston area—and two months later, someone reached out for assistance with a specific project needing a tight turnaround."Literally within 12 hours of them reaching out to us, we replied and committed to three pertinent deliverables, those being a Tapered ISO Design Package, an Assembly Letter confirming all FM Requirements, and last but not least, a conference call the next day with the Building and Roofing Science team to go over three critical transitional details." Allor says.Committing to Successful Project OutcomesThe PVC specialists at GAF are focused on one goal: helping architects, specifiers, and the roofing design community achieve successful project outcomes through a high-performing PVC roofing system. With professionals like Allor providing insight and guidance, you can rest assured your PVC project will be in good hands.Ready to get started on your next PVC roofing project? Explore the different PVC roofing solutions available, and visit this page to find your local PVC roofing specialist who is ready to assist you.*GAF warranties and guarantees do not provide coverage against exposure to chemicals, grease, oils, animal fats or exhaust. Refer to gaf.com for more information on warranty and guarantee coverage and restrictions.