Materials life cycle assessment of a living building

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Materials life cycle assessment of a living building Materials life cycleConference, assessment of aa Nantes, livingFrance buildingb 28th CIRP Design May 2018, a a

Haley Gardner , Julissa Garcia , Vaclav Hasik , Maureen Olinzock , c a aBileca* b , Melissa M.and Banawi Haley Gardner ,analyze Julissa Garcia Vaclav Hasik , Maureen Olinzock , methodology toAbdulaziz thea,functional physical architecture c a , Melissa M. Bilec * Abdulaziz Banawi University of Pittsburgh, 4200 Fifth Ave, Pittsburgh, PA 15260, United States

A new of existing products Pittsburgh for anParksassembly product family identification Conservancy, 45 S.oriented 23 St, Pittsburgh, PA 15203, United States a

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University of Pittsburgh, 4200Al Fifth Ave, Pittsburgh, PA 15260, United States c King Abdulaziz University Ehtifalat St, Jeddah 21589, Saudi Arabia b Pittsburgh Parks Conservancy, 45 S. 23rd St, Pittsburgh, PA 15203, United States c * Corresponding author. Tel: +1 412-648-8075; fax:Abdulaziz +1-412-624-7820. address: [email protected] King UniversityE-mail Al Ehtifalat St, Jeddah 21589, Saudi Arabia

Paul Stief *, Jean-Yves Dantan, Alain Etienne, Ali Siadat

* Corresponding Tel: Supérieure +1 412-648-8075; fax: +1-412-624-7820. E-mail address: [email protected] Écoleauthor. Nationale d’Arts et Métiers, Arts et Métiers ParisTech, LCFC EA 4495, 4 Rue Augustin Fresnel, Metz 57078, France

*Abstract Corresponding author. Tel.: +33 3 87 37 54 30; E-mail address: [email protected]

Abstract Although life cycle assessment (LCA) is a valuable tool to evaluate the built environment’s impacts, many recent studies do not allocate equal attention to each life cycle stage [1,2]. As use phase impacts decrease in high-performance buildings, the significance of other life cycle lifeAcycle assessment (LCA) LCA is a valuable tool to evaluate thebuilding built environment’s impacts, many recent studiesimpacts do not of allocate stagesAlthough increases. process-based material was performed on a living in Pittsburgh, Pennsylvania to quantify other Abstract equal to impactful each life cycle stagewas [1,2]. As use phase impacts significanceperformed of other life cycle stages.attention The most assembly structural, ranging from decrease 25-51% in perhigh-performance TRACI category.buildings, Material the improvements reduced stages increases. A process-based material LCA was for performed on(93%, a living building in Pittsburgh, Pennsylvania to quantify impacts of 43%, other carcinogen, non-carcinogen, and the ecotoxicity impacts structural 56%, and 18% respectively) and architectural materials (93%, Instages. today’s business environment, trend towards more product variety and customization is unbroken. Due to this development, the reduced need of The most impactful assembly was structural, ranging from 25-51% per TRACI category. Material improvements performed and 13%, respectively). production systems emerged to cope with various products and product families. To design and optimize production agile and reconfigurable carcinogen, non-carcinogen, and ecotoxicity impacts for structural (93%, 56%, and 18% respectively) and architectural materials (93%, 43%, systems as well as to choose the optimal product matches, product analysis methods are needed. Indeed, most of the known methods aim to and 13%, respectively). © 2019aThe Authors. Published by Elsevier B.V. This is an open accessproduct article families, under thehowever, CC BY-NC-ND license analyze product or one product family on the physical level. Different may differ largely in terms of the number and © 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). nature ofThe components. This fact by impedes anB.V. efficient comparison and choice of appropriate product family combinations for the production © 2019 Authors. Published Elsevier This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/) Peer-review under responsibility of the scientific committee of the 26th CIRP Life Cycle Engineering (LCE) Conference. system. A new methodology is proposed to analyze existing products in view of their functional and physical architecture. (http://creativecommons.org/licenses/by-nc-nd/3.0/). Peer-review under responsibility of the scientific committee of the 26th CIRP Life Cycle Engineering (LCE) Conference. The aim is to cluster these productsunder in new assembly oriented product families for the optimization existing lines(LCE) and the creation of future reconfigurable Peer-review responsibility of the scientific committee of the 26th CIRPofLife Cycleassembly Engineering Conference. Keywords: life cycle assessment; living building; net zero energy; net zero water; material assembly systems. Based on Datum Flow Chain, the physical structure of the products is analyzed. Functional subassemblies are identified, and a Keywords: functionallife analysis is performed. hybrid functional physical cycle assessment; livingMoreover, building; neta zero energy; net zero and water; material architecture graph (HyFPAG) is the output which depicts the similarity between product families by providing design support to both, production system planners and product designers. An illustrative example of a nail-clipper is used to explain the proposed methodology. An industrial case study on two product families of steering columns of 10% of its life cycle impacts, one study found that material 1. Introduction and background thyssenkrupp Presta France is then carried out to give a first industrial evaluation of the proposed approach. selection canlife account up to 46% a low-energy ©1.2017 The Authors. Published by Elsevier B.V. 10% of its cycle for impacts, one of study found thatbuilding’s material Introduction and background life cycle impacts [2]. With respect to end-of-life of building’s materials, 1.1. High-performance buildings and their life cycle impacts Peer-review under responsibility of the scientific committee of the 28th CIRP Design can Conference selection account2018. for up to 46% of a low-energy

one study impacts found that recycling materials could life cycle [2].the With respectof to building end-of-life of materials, 1.1. High-performance buildings and their life cycle impacts result in a 30% decrease in the life cycle energy of a building; of energy one study found that the recycling of building materials could because study was performed a conventional building, consumption [5]. States, Therefore, any improvements to this sector result in this a 30% decrease in the lifeon cycle energy of a building; In the United buildings account for 39% of energy it can be concluded that these savings would be greater for an can have significant impacts on the reduction of energy use and because this study was performed on a conventional building, consumption [5]. Therefore, any improvements to this sector energy-efficient structure due to the higher significance of the consequently greenhouse gas emissions. There has been a large it can concluded that these savings would be greater and/or for an have significant impacts on the reduction of energy use and of 1.can Introduction the be product range and characteristics manufactured end-of-life phase [6]. This paper focuses on the material phase effort in recent years to design high-performance buildings in energy-efficient structure due to the higher significance of the consequently greenhouse gas emissions. There has been a large assembled this system. this context, the main challenge in of a livinginphase building life Incycle assessment (LCA); a wholeorder to recent reduceyears the energy demand of the building sector. end-of-life [6]. This paper focuses on the material phase effort in to design high-performance buildings in modelling Due to the fast development in the domain of and analysis is now not only to cope with single building LCA will be life completed assessment in the future. Looking at high-performance buildings from a life sector. cycle of a living building wholeorder to reduce the an energy demand of of the building communication and ongoing trend digitization andit products, a limited productcycle range or existing (LCA); product afamilies, perspective (raw materials, production, use, and end-of-life), building LCA will be completed in the future. Looking at high-performance buildings from a life cycle digitalization, manufacturing enterprises arephase facingdecrease, important but also to beBuilding able to analyze and to compare products to define 1.2. Living Challenge is observed that asmaterials, the impacts from the use, use all perspective (raw production, and end-of-life), it new product families. It can be observed that classical existing challenges in today’s market environments: a continuing other life cycle will see from a proportional increase in their 1.2. Living Building Challenge is observed that stages asreduction the impacts thedevelopment use phase decrease, all product tendency towards of phase product times and families regrouped in function of clients features. In 2006, theare Cascadia Green Building Councilor launched significance. Because the use has been found to account other life cycle stages will see a proportional increase in their shortened product lifecycles. In addition, there is an increasing However, assembly oriented product families are hardly to find. version 1 ofthe theCascadia Living Building Challenge (LBC);launched due to for 80-90% of overall cycle impacts of conventional In 2006, Greenproducts Building Council significance. Because thelife use phase has been time found toaaccount demand of customization, being at the same in global On the product family level, differ mainly in two growing interest in this program over its first few years, the buildings, the focus on this stage is justified [1]. Although version 1 of the Living Building Challenge (LBC); duethe to for 80-90%with of overall life cycle impacts of conventional competition competitors all over the world. trend, main characteristics: (i) thewas number of components and (ii) Living Building Institute formed in order to manage the material selection in on a conventional buildings is This onAlthough average growing interest in this program over its first few years, the buildings, the focus this stage is justified [1]. which is inducing the development from macro to micro type of components (e.g. mechanical, electrical, electronical). Living Building Institute was formed in ordersingle to manage the material results selection a conventional buildings on average markets, in indiminished lot sizes due tois augmenting Classical methodologies considering mainly products 2212-8271 © 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license product varieties (high-volume to low-volume production) [1]. or solitary, already existing product families analyze the (http://creativecommons.org/licenses/by-nc-nd/3.0/). To cope with this augmenting variety as well as to be able to product structure on aConference. physical level (components level) which 2212-8271 © 2019 The Authors. Published by Elsevier B.V. This is an open access articleEngineering under the CC BY-NC-ND license Peer-review under responsibility of the scientific committee of the 26th CIRP Life Cycle (LCE) (http://creativecommons.org/licenses/by-nc-nd/3.0/). identify possible optimization potentials in the existing causes difficulties regarding an efficient definition and doi:10.1016/j.procir.2017.04.009 Peer-review under responsibility of the scientific committee of the 26th CIRP Life Cycle Engineering Conference. production system, it is important to have a precise knowledge comparison of(LCE) different product families. Addressing this In theAssembly; United States, buildings account for 39% Keywords: Design method; Family identification

doi:10.1016/j.procir.2017.04.009

2212-8271 © 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/) 2212-8271 © 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of scientific the scientific committee theCIRP 26thDesign CIRP Conference Life Cycle 2018. Engineering (LCE) Conference. Peer-review under responsibility of the committee of the of 28th 10.1016/j.procir.2019.01.021

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LBC and any additional future programs. Today, Cascadia has evolved into Cascadia Green Building Coalition and supports the International Living Future Institute (ILFI), which encompasses the Living Building, Product, and Community Challenges. Each program has similar themes of enhancing quality of life with focuses on promoting social justice, celebrating culture, and ensuring ecological restoration [7]. Because of its extensive and interdisciplinary requirements, this is one of the most challenging building certifications to obtain. To demonstrate how rigorous this rating system is, as of 2017, there are about 6,600 buildings in the world that have received US Green Building Council’s Leadership in Energy and Environmental Design (LEED) Platinum status, yet only 15 that have received ILFI’s Full Living Certification [7,8]. Although LEED has existed for longer, these values illustrate how challenging and noteworthy it is to receive Living Certification. LBC version 3.1 requirements are organized into 7 petals: place, water, energy, health and happiness, materials, equity, and beauty. Each petal has a series of imperatives, for a total of 20, which all must be met to achieve Living Certification. These imperatives encompass a wide range of concepts, including netpositive energy and water, biophilic environment, and beauty and spirit [7]. Achieving this certification requires integrated design strategies, community involvement, and an unprecedented amount of communication between the designers, manufacturers, and contractors, making it a challenging certification process to experience. 1.3. Life cycle assessment of green buildings In recent years, there has been an increase in studies that focus on life cycle stages besides the use phase; there is a growing amount of research regarding material selection and end-of-life because the potential to decrease the environmental impacts from embodied energy of materials is being recognized [9-11]. Embodied energy is a significant component of a building’s life cycle impacts and can be reduced many ways, such as choosing greener materials or considering the end-oflife of the products [6]. However, it is important to note that green buildings can sometimes see an increase in embodied energy from their complex systems, such as solar panels or geothermal wells [12]. Researchers have therefore discovered that there are many tradeoffs between material selection and lower building impacts. Selecting more sustainable materials could include choosing materials that are locally sourced, have fewer toxins, or have a higher recycled content, all of which have the potential to result in lower life cycle impacts. Additionally, as for end-of-life, recycling and repurposing cut down on overall life cycle impacts as they results in less material being introduced into both manufacturing processes and waste streams [13]. The USGBC, ILFI, and other green building rating system organizations have recognized that materials have a significant effect on building life cycle impacts and have therefore implemented many materials requirements into their certifications [7,8,14]. Therefore, this LCA assesses the materials used in a living building in order to determine the effect on of material selection on the overall building life cycle impacts.

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2. Methods 2.1. Case study description The Frick Environmental Center (FEC) sits on the edge of Frick Park, the largest park in the greater Pittsburgh area. It is a municipally-owned, public facility that is a joint venture between the City of Pittsburgh and the Pittsburgh Parks Conservancy (PPC); it is meant to serve as a resource for visitors to the park by welcoming them into the center and subsequently ushering them out into the nearby landscape [15]. The building is comprised primarily of office space for staff as well as classrooms, which are used for the numerous educational events (i.e. summer camps, nature classes) hosted by the PPC at this facility. The FEC is a 3-story, 15,000sf building that has a primarily steel framing and concrete foundation. Because it is netpositive energy and water, the site contains many sustainable systems and strategies including solar panels, geothermal wells, a rainwater collection and purification system, permeable pavement, passive ventilation, and daylighting. There are four structures on site: the main building, a service barn, and two gatehouses that date back 70 years. The construction began in 2014 and the facility opened in 2016. Due to the extensive sustainable features present in this facility, it is both LEED Platinum and Certified Living by the ILFI. Additionally, the previous structure on-site was destroyed due to arson, providing the community with the unique opportunity of reimagining the facility; the decision to construct a new building with such sustainable features reflects Pittsburgh’s commitment to creating a greener future. This four-acre site encompasses the main building, two historic gatehouses, a historic fountain, a service barn, an outdoor amphitheater, and a parking lot covered by a photovoltaic (PV) structure (see Fig. 1). a

b

c

d

Fig. 1. (a) Historic fountain; (b) PV parking lot structure; (c) Main building; (d) Historic gatehouse.

2.2. LCA methodology As detailed by the International Organization for Standardization (ISO), life cycle assessment consists of four major steps: goal and scope definition, life cycle inventory (LCI), impact assessment (LCIA), and interpretation of results

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[16]. The goal and scope stage defines the project purpose and system boundary. The LCI presents all of the data used for the assessment; materials selected, energy used, and waste generated are some of the primary flows that are measured and assessed. The LCIA quantifies the impacts and significance of the inventory; these impacts are then evaluated, interpreted, and contextualized. The primary life cycle stages of a building are raw material extraction, material manufacturing and processing, construction, use, and end-of-life. This LCA assesses the material stages, as seen in Fig. 2

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where building materials were counted and their totals exported [17]. Various dimensions could be input directly into the software, allowing for efficiency of exporting only desired quantities. For example, the dimensions of ducts could be added such that the total square footage is directly exported. Although final quantities were primarily assessed by material type, the takeoff was performed in such a way that they can also be analyzed by totals per floor should this alternate analysis options prove to be valuable. As for the material attributes and composition, LEED and LBC material submittals, Environmental Product Declarations (EPDs), and material submittals from manufacturers were also used to obtain specific material attributes (see Section 2.6). 2.4. Life cycle inventory

Fig. 2. Focused material scope from entire life cycle system boundary.

The aforementioned quantity takeoff is a critical component of compiling a life cycle inventory. The components of each assembly (structural, architectural, mechanical, water systems, and energy systems) are accounted for in this inventory as seen in Fig. 3. Each assembly is then comprised of material subassemblies. For example, the structural assembly contains concrete, which is composed of cement with fly ash, river gravel, and river sand. A unit process was acquired for the materials within each subassembly in order to ascertain impact factors for every TRACI (Tools for Reduction and Assessment of Chemicals and other Environment Impacts) impact category (e.g., Global warming potential, Ecotoxicity) using the SimaPro software [18]. Each material’s unit process is organized in the LCI, as well as the database of origin, the specific material, product lifespan, and any additional information (i.e. percent breakdown when many components comprise one material). A portion of the LCI can be found in Table 1.

2.3. Material phase Although the Living Building Challenge is an extensive building rating system, there is room for improvement. One area specifically is the quantification of material impacts, including material selection and embodied energy. In LBC 3.1 (2017), there are no imperatives related to material embodied energy; there is only one imperative that requires offsets for the embodied energy of solely the construction phase [7]. As previously discussed, as the use phase of high-performance buildings decrease, all other life cycle stages increase in significance and require more evaluation; this prompts a need to assess building materials in greater detail in order to quantify the changing impact distribution of building life cycle phases. Therefore, a significant component of this LCA was the evaluation of building material selection, which is used herein to refer to the collective stages of material extraction, manufacturing and processing, and transportation. A holistic and detailed quantity takeoff was performed on the main building of the Frick Environmental Center to obtain accurate material totals. As-built construction documents were provided to the research team by the contractors. These documents were uploaded to the software On-Screen Takeoff

Fig. 3. Breakdown of each assembly and material subassembly.

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2.5. Life cycle material impact assessment After the LCI is complete, the impact assessment stage was conducted using TRACI. Any attributes acquired from the aforementioned product submittals were also integrated into the specific material unit process, such as percent recycled content. Adding these additional attributes will result in a greater accuracy of the life cycle impacts of this building. 2.6. Material quantities and attribute adjustments One issue with respect to the life cycle assessment of highperformance buildings is that unit processes present in commercial or publicly available life cycle databases may not be truly reflective of novel or ‘green’ materials. A common example of one material that has been improved over the years is the use of asbestos in building insulation. Once the US EPA and US Department of Health and Human Services declared asbestos a carcinogen, all new forms of it were banned [19]. Now, safer types of insulation are used. Because these new alternatives are becoming a common practice, unit processes for these materials exist in LCA databases and can be selected when appropriate. This concept of updated unit processes needs to now be extended to a multitude of other materials as greener options emerge. Recently, there has been an increase in material transparency, which will make it easier over time to input material attributes into LCA databases. The ILFI created the material transparency label called Declare wherein manufactures share various features including a precise list of ingredients, life expectancy, management at end-of-life, and if Table 1. Life cycle inventory of structural materials. Each unit process comes from the ecoinvent 3 database, the service life of each structural material is 75 years [4]. Assembly

Material Portland Cement (No fly ash)

Unit Process Cement, Portland {US}, market for, Alloc Def, U

Notes 20% weight

Sand {GLO} market 40% weight CMU Blocks River Sand for Alloc Def, U Gravel, crushed, 40% weight River Gravel {ROW}, market for, Alloc Def, U Portland Cement, pozzolana 10% weight Cement and fly ash 15-40%, (includes fly US only, market for, ash) Alloc Def, U Gravel, crushed, 30% weight Concrete Gravel {ROW}, market for, Alloc Def, U Sand {GLO} market 60% weight Natural Sand for Alloc Def, U Steel, low alloyed 88.4% Steel Steel {GLO}, market for, recycled Beams Alloc Def, U content Steel, low alloyed 77.6% {GLO}, market for, recycled Steel Steel Plates Alloc Def, U content Reinforcing Steel, 99.4% weight Steel market for, Alloc Reinforced Rec, U Steel, low alloyed 0.6% weight Steel Steel Alloys {GLO}, market for, Alloc Def, U

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it contains any materials on what is called the Red List. Also created by the ILFI, this list includes chemicals common in building materials that have high potency with respect to environmental pollution, bio-accumulation, and negative human health impacts on construction/factory workers [7]. As these transparency efforts continue, general databases containing this updated material information are beginning to emerge; however, there is still a disconnect between the information itself and the integration of this updated information into databases used during LCA. In order to accurately determine the impacts of buildings that use greener materials, it is imperative that the information used to assess material impacts reflects the use of these healthier products. Therefore, an additional analysis of this whole building LCA was performed on preliminary material adjustments to demonstrate how to improve the accuracy of green building LCAs. For this paper, structural and architectural material adjustments were made. Because living building materials cannot contain any Red List chemicals, all of these toxins’ impacts were removed. In order to effectively remove these impacts, every toxin’s contributions were subtracted from each material’s inventory. The Red List contains 21 general chemicals but is broken down into 815 specific chemicals. For example, the single item “Chlorofluorocarbons (CFCs) and Hydrochlorofluorocarbons (HCFCs)” encompasses 90 individual chemicals [7]. These 815 chemicals were queried and subsequently removed from each material inventory of 2,000 chemicals; since all 10 TRACI impact categories were assessed for both the structural and architectural assemblies, a total of 20 inventories were evaluated and adjusted. A material tracking sheet was provided by the building designers that designates whether or not a material was Red List free (RLF) or if an exception was made; therefore, a product was only adjusted if it is noted as RLF. These adjustments consequently result in a more representative impact factor for the greener materials and overall more accurate whole building LCA impacts. All 10 TRACI impact categories were assessed for structural and architectural assemblies in order to identify where the largest impact reductions are made as a result of being RLF. Future assessments include Red List adjustments for materials in the MEP, water, and energy system assemblies. 3. Results and discussion 3.1. Overall LCA results of material impacts Based on the building material quantities and improved impact factors, results were acquired for each material assembly. Table 2 shows the breakdown of each assembly for a given TRACI impact category. These findings show that structural components have the largest impact for each category, with a median contribution of 40%. However, materials in both the PV and mechanical systems also have significant impacts for many of the categories, with maximum contributions of 22% and 32%, respectively. These results show the hotspot areas within material impacts, which can provide building designers with insight when it comes to

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material selection; focusing on choosing more sustainable structural materials has the potential to drastically decrease the overall building material impacts. Table 2. Preliminary material impact percentages, by TRACI impact categories [3]. Impacts of the categories (Architectural, Structural, Mechanical, Water, Geothermal, PV System) from left to right are: Ozone depletion (kg CFC-11 eq), Global warming potential (kg CO2e), Smog (kg O3e), Acidification (kg SO2e), Eutrophication (kg N eq), Carcinogens (CTUh), Non-Carcinogens (CTUh), Respiratory effects (kg PM2.5e, Ecotoxicity (CTUe), and Fossil fuel depletion (MJ surplus). Results of Red List impact factor adjustments made for the architectural and structural

GWP (%)

SFP (%)

AP (%)

NCar (%)

RE (%)

ETX (%)

FFD (%)

12

9

13

14

8

1

4

17

6

16

S

42

51

44

33

41

43

38

36

35

25

M

15

14

17

23

14

18

32

16

30

20

W

6

7

7

8

8

27

12

8

13

15

G

9

7

11

11

7

3

5

7

6

16

P

16

11

8

11

22

8

9

16

10

8

Σ%

100

100

100

100

100

100

100

100

100

100

Car (%)

OD (%)

A

EP (%)

Assembly

assemblies are reflected below.

3.2. Material improvements results for green materials Once the previously described material adjustments were performed, there were noticeable decreases in several building material impact categories. As for the structural material Red List adjustments, the most substantial changes in overall impacts occurred in three categories: Carcinogens (-93%), Non-carcinogens (-55%), and Ecotoxicity (-18%), as seen in Table 3. These reductions are a result of the decreases in the impact factors via subtracting contributions from Red List chemicals, as seen in Fig. 4. These decreases in overall total impacts support the efforts of the ILFI and the Red List as the manufacturing of greener products is reducing impacts in the categories they are targeting, namely those that affect human health and ecosystems. However, it does highlight that there is room for improvement with respect to many other categories, such as global warming potential or smog production which saw little to no improvements. Therefore, it is recommended that green building rating systems strive to evaluate buildings holistically because solely choosing RLF materials would result in no reduction of the material’s embodied energy of a material, but rather exclusively its carcinogenic or ecotoxic quality. 4. Future work End-of-life impacts of structural materials were assessed, and preliminary results showed that structural steel and concrete accounted for a significant amount of every TRACI impact category. If alternate disassembly strategies are analyzed for these select materials, either to reflect the actual fate of the material or to model the least impactful disposal

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option, their total life cycle impacts could change. One study compared the environmental effects of structural steel and concrete and found that the CO2 emissions for a hollow steel framed building were only 15% of those of a cast-in-place concrete framed structure [20]. A similar scenario analysis will be performed on the FEC to see how different the life cycle impact of the structure would be if its concrete components were replaced with steel or wood components. It should be noted that the wood scenario will factor in biogenic carbon impacts, as these are imperative to consider when assessing wooden structures [21]. This scenario analysis will determine how these three structural components compare specifically with respect their end-of-life impacts. Additionally, a substitution component will be explored for the Red List material adjustments. For example, it may be the case in some materials that during a manufacturing process a certain Red List chemical might be replaced with a different material or process, rather than just being removed completely from the system. This requires a more in-depth analysis of material manufacturing but will improve the accuracy of the adjusted material impact factors. Additionally, once the whole building LCA is finalized, the total impacts will be compared to conventional buildings, as well as other certified LEED and Living Buildings. A comparison will also be made to results from an FEC baseline, which includes no material adjustments, to discern the discrepancy between LCAs using standard data versus data with material adjustments made. This will allow for a discussion about which green design strategies decrease life cycle impacts, as well as any hotspots identified in the LCA that can further improve green building design. Finally, a statistical analysis will be performed on the whole building LCA results to ensure accuracy. The Monte Carlo method will be used in order to get deterministic values once the LCA is complete. Table 3. Preliminary percent change from original to RLF total material impacts, structural materials without replacements. TRACI Impact Category

Units

Percent change

Ozone depletion Global warming potential Smog Acidification Eutrophication Carcinogens Non-Carcinogens Respiratory Effects Ecotoxicty Fossil fuel depletion

kg CFC-11 eq kg CO2 eq kg O3 eq kg SO2 eq kg N eq CTUh CTUh kg PM2.5 eq CTUe MJ surplus

-8.72% 0.00% -0.04% -0.13% -0.02% -93.18% -56.31% -0.07% -18.44% 0.00%

5. Conclusion Now that the design of specifically low-energy buildings is abundant, it is time to expand the scope of thinking from the only the use phase to the entire building life cycle. The material impacts and end-of-life stages account for a greater percentage of the building life cycle for these high-performance structures, and efforts should now be made to further minimize these impacts. From the material impact assessment, it was discovered that structural components of the Frick

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Environmental Center contribute the most significant impacts for all TRACI impact categories; this provides potential for design improvements moving forward since this has been identified as a hotspot in the building life cycle impact. A challenge faced by LCAs of buildings that are this conscientious about their design is that there are not ample data in assessment databases to reflect efforts made. This primarily applies to material selection. Obtaining Living Certification requires great effort when it comes to material selection as to minimize toxicity and environmental impact. The material databases to date do not include such detailed information; therefore, whenever an LCA is performed, it does not reflect the true total building impact and is potentially much larger. This work seeks to incorporate these specific material attributes into the material unit processes to obtain more accurate totals of the whole building impacts. In addition to material selection impacts, end-of-life impacts must be considered as the use phase is reduced. The impacts of steel, concrete, and wood were compared as not only are these the three primary structural components in the building, but steel and concrete dominate the structural assembly total impacts; therefore, taking a closer look at these three materials could help identify how to further minimize the impacts of the assembly that has the largest negative environmental impacts. This whole building LCA seeks to provide insight into the impacts of a high-performance, living building. This work fills a gap in literature with respect to the life cycle assessment of living buildings because they are still emerging. Additionally, this research sheds light on the decreased impacts as a result of more sustainable material selection while providing insight as how to potentially reduce the end-of-life impacts of the building. While this assessment is specific to the FEC, the results of the whole building LCA can be used to shift the focus from the decreasing use phase to life cycle stages with rising impacts. Preliminary median percent change from original to RLF material impact factor per TRACI category, without replacements 0% -10% -20%

OD

Car

NCar

-6% -12%

ETX

-13% -18%

-30% -40%

-43%

-50% -60%

-55%

-70% -80% -90% -100%

-93% -93% Architectural Components

Structural Components

Fig. 4. Median percent decrease in impact factor for each TRACI category after removal of Red List materials. TRACI Categories left to right: Ozone Depletion, Carcinogens, NonCarcinogens, and Ecotoxicity. Categories with <1% change not shown.

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Acknowledgements This work was supported by the University of Pittsburgh’s Mascaro Center for Sustainable Innovation. We would like to thank the Pittsburgh Parks Conservancy for their continuous support and guidance. This research is based on work funded by the National Science Foundation under 1038139 and 1323190. References [1] Ramesh T, Prakash R, Shukla KK. Life cycle energy analysis of buildings: An overview. Energy and Buildings 2010;42:1592-600. [2] Sartori I, Hestnes AG. Energy use in the life cycle of conventional and low-energy buildings: A review article. Energy and Buildings 2007;39:249-57. [3] Bare J, Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts (TRACI) User’s Manual, Washington, D.C., USA; US Environmental Protection Agency, 2012. [4] Frischknecht R et al. The ecoinvent Database: Overview and Methodological Framework (7 pp). The International Journal of Life Cycle Assessment 2005;10:3-9. [5] 2018 Annual Energy Review, Washington D.C., USA; US Energy Information Administration. [6] Blengini GA. Life cycle of buildings, demolition and recycling potential: A case study in Turin, Italy. Building and Environment 2009;44:319-30. [7] Living Building Challenge 3.1: A Visionary Path to a Regenerative Future, Seattle, WA; International Living Future Institute, 2016. [8] LEED v4 for Building Design and Construction, Washington, D.C.; US Green Building Council, 2018. [9] Abd Rashid AF Yusoff S. A review of life cycle assessment method for building industry. Renewable and Sustainable Energy Reviews 2015;45:244-48. [10] Cellura M, Guarino F, Longo S, Mistretta M. Energy life-cycle approach in Net zero energy buildings balance: Operation and embodied energy of an Italian case study. Energy and Buildings 2014;72:371-81. [11] Zabalza Bribián I, Valero Capilla A, Aranda Usón A. Life cycle assessment of building materials: Comparative analysis of energy and environmental impacts and evaluation of the eco-efficiency improvement potential. Building and Environment 2011;46:1133-40. [12] Thiel CC, Landis AE, Jones AK, Schaefer LA, Bilec MM. A Materials Life Cycle Assessment of a Net-Zero Energy Building. Energies 2013;6:16. [13] Blengini GA, Di Carlo T. The changing role of life cycle phases, subsystems and materials in the LCA of low energy buildings. Energy and Buildings 2010;42:869-80. [14] Institute IWB. (2018). WELL v2 pilot. Available: https://v2.wellcertified.com/v2.1/en/materials [15] Frick Environmental Center. Available: https://www.pittsburghparks.org/frick-environmental-center [16] Finkbeiner M, Inaba A, Tan R, Christiansen K, Klüppel H-J. The New International Standards for Life Cycle Assessment: ISO 14040 and ISO 14044. The International Journal of Life Cycle Assessment 2006;11:8085. [17] OST 3.95 - Welcome to On-Screen Takeoff 3.95, Houston, TX; On Center Software, 2018. [18] PRé Consultants, SimaPro v8.5.2; PRé Sustainability, 2017. [19] US Department of Health and Human Services. Toxicological Profile for Abestos. US DHHS Public Health Service, Agency for Toxic Substances and Disease Registry 2001;441. [20] Guggemos AA, Horvath A. Comparison of Environmental Effects of Steel- and Concrete-Framed Buildings. Journal of Infrastructure Systems 2005;11:93-101. [21] Fouquet M et al. Methodological challenges and developments in LCA of low energy buildings: Application to biogenic carbon and global warming assessment. Building and Environment 2015;90:51-59.