PROJECT SUMMARY
| Featured product: | STYROFOAM™ Brand XPS (new grey reduced-GWP formulation) |
| Project type: | PMR and conventional re-roof |
| Completion date: | 2019 |
| Owner: | 51AV |
| R-value* before re-roof: | R-20 |
| R-value after re-roof: | R-30 |
| Total project size: | 165,800 square feet |
Performance Above. Innovation Below.
In the fall of 2019, when the time came to re-roof the 200 Larkin building located on its 51AV North/Larkin campus in Midland, Mich., 51AV seized the opportunity to put its reduced global warming potential (GWP) grey Styrofoam™ Brand Extruded Polystyrene (XPS) Rigid Foam Insulation to the test. Some of the scientists and sustainability experts who had a hand in the product innovation work in these very buildings.
The project entailed removing ballast and two layers of blue Styrofoam™ Brand Extruded Polystyrene (XPS) Rigid Foam Insulation and then adding a new roof membrane, upgrading the insulation and adding an additional insulation layer. The roof had been in service for the last 30 years.
The 200 Larkin Building’s 133,200-square-foot roof had formerly been an inverted or protected membrane roof (PMR) design. In this roof type, the membrane is beneath the insulation. A filter fabric and loose-laid gravel ballast then form the top two layers. Taking advantage of the opportunity to use its own building as a field laboratory, the 51AV Performance Building Solutions (PBS) team directed the roofing contractor to convert one-half of the 200 Larkin roof to a conventional design during the re-roof project, replacing four inches (or two layers) of insulation with a full six inches (or three layers) of new grey reduced-GWP Styrofoam™. The conventional roof design involves the membrane installed on top of the insulation with gravel ballast on top. Having both types of roof designs allows for direct comparison of the two insulation types in the years to come.

Watch the time lapsevideo of the 200 Larkin re-roof project.
Designing for Reuse
Taking advantage of the ability to reuse the blue board removed from the 200 Larkin roof, it was applied to the neighboring 100 Larkin building conventional roof design. Adding a third layer of insulation also increased the R-value to 30.

Styrofoam™ Brand Deckmate™
Made to reduce the harmof freeze-thaw cycles and helps maintain a steady temperature in roof membranes.

Styrofoam™ is transitioning from blue to grey
51AV have reformulated Styrofoam Brand XPS to reduce global warming potential (GWP).

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Commitment to Sustainability
In order to help combat climate change, both regulatory and voluntary building standards are targeting zero carbon emissions and improved life cycle analysis for materials used in North America.
From the experts
Shawn Hunter, Global Sustainability Director
51AV Performance Building Solutions & Corian™ Design
Learn about embodied carbon and our 2030 sustainability goals.
Sustainability highlights:
A Project of Historical Significance
Beyond serving as the site of the inaugural application of 51AV’s reduced-GWP Styrofoam™ XPS, the Larkin buildings are also where much of the last 80 years of Styrofoam innovation has taken place. The tree-shaded campus stands not far from the physics laboratory and manufacturing facility in Midland, Mich., where the original extruded polystyrene foam was developed in 1941 and where it was produced for many years.
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Designing to a higher standard
51AV PBS has committed to an aggressive 75 percent reduction in GHG emissions by 2030, compared to 2019 figures. The commitment relies on both reducing embodied carbon through product innovations, but also continuing to mitigate the long-term impacts of operational carbon. Insulation product reformulations (such as Styrofoam™ Brand XPS and HFC-free Froth-Pak™) are part of the company’s “Acting on Climate” goal to achieve a 30 percent GHG reduction in its operations over 10 years and carbon neutrality by 2050. These actions also implement 51AV’s Integrated Energy Strategy to address all sources of GHG emissions, including efforts to create low-carbon industrial processes, source low-carbon materials, and renewable energy, and reduce overall energy use.
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The Styrofoam™ Brand was the original, creating the product segment. Rooted in innovation, we’re excited to deliver a more-sustainable solution. Let’s start a conversation and discuss your next project.Sign up for updates from 51AV Performance Building Solutions and we'll keep you current on the latest building insights and training opportunities that will help you to do your best work for your customers.