Climate Responsive Facade Optimization Strategy
by Rudai Shan
The building facade plays a key role in the entire building's energy performance. In commercial buildings, energy demand is dominated by space heating, cooling, and articial lighting. Facade design variables for these three factors have always been interacting and sometimes even in con ict with each other. For dierent climates, adaptive facade design solutions should be implemented to achieve optimal design objectives, such as energy performance, human comfort, and life cycle cost. While the optimal solution is traditionally identied through \trial-and-error", for complex optimization problems that contain a great number of design variables, it might require extensive hours of computation at early design stage, a condition that is increasingly infeasible in practice due to cost or time constraints.
Since 2008, there has been a signicant trend in building performance optimization techniques (that used to emphasize solely on simulation) being implemented, instead of building simulation techniques, to obtain design solutions for building performance optimization problems. Among widely implemented optimization algorithms, the genetic algorithm (GAs) have proven eective with its robustness in dealing with discontinuous variables. However, for complex optimization problems with a great number of variables, such as facade performance optimization (FPO) problems, GAs are still too time-consuming to be implemented at the early design stage, thus e- ciency becomes the main area for its augmentation.
The main objective of this study is to develop a new evolutionary algorithm method, adaptive radiation (AR), based on simple GAs to solve complex optimization problems relative to the design approach of the climate-responsive facades. AR is derived from the biological process of adaptation where specic species are evolutionarily adapted to their immediate ecological niches. This process can obtain optimal solutions of facade design variables (inltration, window-to-wall ratio, shading geometry, glazing types, wall insulation, etc.) in signicantly less computation time than GA. In this study, AR is implemented in three dierent climates in the United States to demonstrate its robustness and eciency.
Building the Working City - Designs on Home and Life in Boomtown Detroit, 1914-1932
by Michael McCulloch
The modern worker’s home made Detroit’s Fordist industrialization possible. Between the 1914 announcement of Ford’s “Five Dollar Day” and the Great Depression, Detroit industrialists, real estate developers and workers produced a building boom in housing, reshaping the urban society and negotiating the terms of what Antonio Gramsci called “a new type of worker and of man.” Expanding the architectural history of Fordism beyond the factory, this dissertation argues that it was through the modernization of the larger city—a Fordist Urbanism dominated by worker’s housing developments between the city’s peripheral industrial plants—that Detroit’s Fordist culture was constructed. Industrialists promoted modern worker’s housing, pursuing social control of the city’s largely-immigrant workforce, but shifted the risk of housing construction costs to individual workers by pushing them to seek houses on the open market. Real estate developers responded, and with government support built tens of thousands of bungalows and duplexes for sale to workers on credit. Realtors presented homeownership as a source of financial security for workers yet a realty culture of speculative investment and racial segregation undermined that security from the beginning. At the same time workers had significant agency in this city-building process. They produced more than industrial products in Fordist Detroit, making domestic lives and identities in the pluralistic ways that they chose, outfitted, lived in and cared for their homes, giving meaning and purpose to their routinized labor. Detroit’s industrial modernization—in and through its modern worker’s houses—elaborated crises of racial violence and home foreclosure in the mid 1920s and early 1930s, in which workers fought against one another, and ultimately in solidarity, demanding that the Fordist promise of hard work in exchange for domestic security be honored. Detroit’s houses of the early twentieth century, the extant and the demolished, still contain a great deal: a history of power negotiated through the modernization of the built environment. This past suggests that the city’s future housing can influence the management of risk within society, the social construction of difference, and workers’ continued struggle for security.
Making Exceptions: Politics of Nonconforming Spaces in the Planned Modern City of Islamabad
by Faiza Moatasim
This dissertation explores spatial nonconformity as a central feature of contemporary city-making. Nonconforming urban phenomena in planned modern cities of the twentieth century have mostly been conceptualized as contradictions to the ideal “plan” (Epstein, 1973; Sarin, 1982; Holston, 1989). An examination of the functioning and everyday life of these planned places, however, reveals that rather than being marginal dysfunctional phenomena, spaces that do not conform to formal architectural and planning protocols play a central role in the way abstract plans are operationalized, and planned cities are experienced. In the planned modernist city of Islamabad, the capital of Pakistan designed in 1959 by Greek architect-planner Constantinos A. Doxiadis, a range of actors, including both marginalized and affluent residents and business people along with government functionaries, routinely engage in creating and furthering nonconforming spaces in order to increase access to certain functions, privileges, and necessities that cannot be otherwise delivered through formal planning and architectural practices. My research on Islamabad advances a conceptualization of nonconforming spaces not simply as contradictions to an ideal plan but in terms of rights and entitlements that flow in situations normatively characterized as existing outside the purview of law.
Examples of nonconforming spatial practices in Islamabad include: a) illicit residential constructions that range from overcrowded dwellings built along open drains to sprawling mansions set on expensive lakefront properties, (b) unauthorized uses of authorized buildings, and c) encroachments on greenbelts and sidewalks by poor café owners, street hawkers, formal businesses, foreign diplomatic missions, and government organizations, to name a few. By investigating nonconforming urban development in the planned city of Islamabad, my research asks the following questions: What is the relationship between spaces that are planned formally and informally in the case of a comprehensively planned city? What are the similarities and differences found in the spatial practices and political motivations of both state and non-state actors engaged in creating nonconforming spaces? Why are certain nonconforming spaces tolerated for long periods of time while others are strongly resisted by the city’s municipal and developing authority?
Recent scholarship on urban informality has demonstrated the relevance of nonconformity in urban development processes around the world, and highlighted the profusion of informal practices in governmental planning procedures (Roy, et. al., 2004). My research on Islamabad extends this discussion by showing how the “informalization of the State” is accompanied by a “formalization of the Everyday” as ordinary citizens (both the rich and the poor) strategically mimic official planning procedures in order to create the effect of legitimacy to justify urban spaces that do not conform to official planning frameworks (Roy, 2004, p. 159; Hull, 2012). Together these two constructions reject the informal - formal divide in favor of complementary and co-constitutive alliances, and help improve our understanding of contemporary trends in the development and administration of urban areas. My dissertation thus attempts to trace a contemporary history of Islamabad by focusing on the politics of creating nonconforming spatial exceptions as they emerge in spatial practices and political tactics of government functionaries, privileged and underprivileged residents, and business people of the planned city. In this investigation spatial nonconformity emerges as an important feature of contemporary planning paradigms, which are not unique to Islamabad but are relevant to urban conditions found in modern cities everywhere.
Essays on Analytic Methods Applicable to the Micro-Geography of the Workplace
by Yongha Hwang
In spite of growing interest in the physical environment’s role in better communication and collaboration in knowledge-intensive organizations, far too little attention has been paid to quantitative methods for describing and analyzing micro-geography of the workplace. Three essays in this dissertation explores novel methods for describing a spatial layout and analyzing its effect on organizational communications.
The first essay’s main question is how concentration of movement fosters diverse communication in the space. We articulate the concept of confluence and propose a new metric, sociospatial betweenness to measure the confluence of a space. Sociospatial betweenness of a space was found to be positively associated with the diversity of communication partners among a group of professionals in a manufacturing company; in contrast, traditional spatial betweenness did not show such an association.
The second essay addresses how exposure between members of a dyad increases the chance of research collaboration. The essay proposes and develops a novel metric, zone overlap, measuring exposure, the likelihood of mutual encounter between two people, based on the location of one’s workstation and commonly used facilities. We collected administrative data on a sample of research scientists working at two biomedical research buildings with different layouts. We found that increasing path overlap is associated with increases in collaborations in both buildings. In contrast, traditional metrics such as walking distance and straight-line distance influence outcome measures in only one of the research buildings.
The third essay introduces a novel approach for subspace decomposition that can be used for the two new metrics, zone overlap and sociospatial betweenness, proposed in the two previous essays. Although spatial decomposition is one of the essential processes for the analysis of building layout, no new rigorous decomposition has been proposed for more than a decade until this study. We demonstrated that the new method successfully addresses the problems of traditional methods. The essay introduced the modularity function as a quality function to evaluate the goodness of spatial decomposition. Previous decomposition methods so far have rarely paid attention to the evaluation of decomposition.
Optimal Control Methods for PV-integrated Shading Devices
by Sung Kwon Jung
The main reason for the under-utilization of natural light is glare caused by excessive admission of daylight into interior spaces. Absence of a dynamic and effective shading control system entails leaving shading devices at a closed position for glare prevention. For increasing building energy efficiency, it is imperative to develop shading control methods that provide both visual comfort and electric lighting energy savings.
A tracking PV system has higher light-to-electricity conversion efficiency than its fixed counterpart. Previous studies on louver controls indicate that louver slat surfaces blocking sunlight receive higher solar radiation than a vertical or tilted-up position. As such, a louver coated with photovoltaics cells, when appropriately controlled, has potentials to achieve high energy production efficiency and visual comfort simultaneously. This is the motivation of the development of a novel hybrid of PV system and shading device: a PV-integrated shading device (PVIS).
The performance of a PVIS, whose louvers are coated with photovoltaic cells, was evaluated in terms of electricity production, daylight admission, and occupant visual comfort. Three different shading control methods were developed and tested: 1) maximizing the louver PV output only, 2) maximizing the PV output while meeting an indoor daylight level requirement and 3) maximizing the PV output while satisfying an indoor daylight level and daylight glare criteria. An artificial neural network was developed to predict the effect of solar radiation and slat tilt angle on PV output and visual comfort.
Through experimental testings, it was found that artificial neural network can effectively incorporated in the optimization of shading control. It was also found that the control method with the visual comfort criteria resulted in 9% reduction of PV output compared to that without them. The total building energy benefits of the control method with visual comfort criteria was at least 36% higher than that without due to the reduction of electric lighting energy consumption. Due to the PV-output criterion, the daylight glare remained within the comfortable range. For this reason, the glare criterion made no difference in louver tilt angle control.
Active Centers - Interactive Edges
by Conrad Kickert
This dissertation explores the deteriorating relationship between architecture and public space plaguing many Western urban cores as a result of economic, cultural, political and social forces. It investigates the question of how and why ground floor frontages have been transformed, by comparing the urban cores of The Hague (Netherlands) and Detroit (United States) over the past century. Frontage interactivity is defined as the combination of physical transparency, functional permeability and perceptual hospitality, and is mapped in both urban cores over the span of a century in 10 to 25 year intervals. Interactivity is categorized into four tiers, based on fourteen functional frontage types, ranging from highly interactive retail businesses to dwellings and less interactive offices, parking structures and warehouses. Patterns of physical and functional fringe belt formation and urban erosion are found in the maps and statistical analyses. These analyses demonstrate a pattern of fringe interactivity decline, amplified by an acceleration of decline at the level of the street segment – pointing to the contagion of vacancy and inactive land uses. This interactivity erosion is usually followed and amplified by a rapid morphological change, often fueled by large-scale urban renewal interventions – a pattern that is surprisingly similar in both cities. The forces behind frontage transformation are illustrated by separate histories of The Hague and Detroit. The demonstrated forces and patterns of change are integrated into a set of conclusions, finding significant similarities between both case studies. From an economic, social and cultural perspective both cities have faced and still face similar challenges, albeit amplified in Detroit. The relationship between buildings and public space has deteriorated significantly in downtown Detroit as a result of socio-economic decline, amplified by a culture favoring progress over sustaining a collective memory. The Hague’s inner city has benefited from a somewhat finer balance between progress and permanence, often due to fierce public and political debates. The conclusions are followed by a set of recommendations for how to counter frontage deactivation, focusing on the role of economics, diversity, curbing fear and auto-mobility, and critical mass in reshaping the architecture of public life.
The Origins of Vancouverism: A Historical Inquiry into the Architecture and Urban form of Vancouver, British Columbia
by Robert Walsh
This study focuses on understanding the development of Vancouverism, a new variety of high density residential urbanism responsible in recent years for the visible transformation of Vancouver, British Columbia. The emergence of Vancouverism has coincided with recognition of Vancouver as a livable city, stimulating widespread interest in this urban phenomenon. However, significant fundamental questions warrant reexamination. How did Vancouverism originate? Does Vancouverism represent a new generalizable urban solution that should work well in other cities, or is it a skillful response to a unique cultural, economic and physical context? Understanding what Vancouverism is, why it is successful in Vancouver, and the relevance that it might have to other urban settings are questions directly linked to better understanding the origins of Vancouverism.
The research begins by proposing a framework of five essential elements that together provide a workable description of Vancouverism: Spaced Point Towers, Row House Enclaves, Active Urban Landscape, Outdoor Urban Rooms and Protected Public Views. In the historical analysis that follows, the development of Vancouverism is traced though the successive introduction of these elements. Drawing from a wide range of source material, including: built projects, un-built proposals, planning documents, archival photographs, discussions with many key participants and original photographs by the author, this dissertation argues that Vancouverism emerged over the course of an entire century as the city itself struggled to adapt to changing local conditions.
Although several general factors proved relevant, including changing building technologies and the global flow of capital from Asia, the physical form of development in Vancouver was ultimately defined by local architects who initiated a protracted search for new, precedent-defying solutions better able to respond to local conditions. The new perspective offered by this research dismantles entrenched misconceptions that suggest Vancouverism was imported from elsewhere or recently invented. Instead, new lessons become available focused on improving processes for developing innovative, locally relevant urbanism and better understanding the contribution that local design knowledge can play in facilitating successful urban revitalization.
A Structural Basis for Surface Discretization of Free Form Structures: Integration of Geometry, Materials and Fabrication
by Aysu Berk
This study focuses on free form surfaces and the challenges of construction due to the complex geometry. A unique approach is proposed that incorporates attributes of form, material selection and fabrication methods of free form surfaces into the early stage of design in aid of optimum mesh generation towards redesigning a practically constructible structure. Free form surfaces need to be discretized into panels with manageable sizes so that the surface can be fabricated in smaller pieces that are all assembled on site. Planarity has been a significant constraint for free form discretization because brittle materials, such as glass, can fail suddenly, without any warning. Triangulation has been a common pattern for free form surface discretization, where the panels are always planar. Due to node complexities of triangulated meshing, quadrilaterals are considered as an alternative pattern for free form surfaces. However, the biggest problem with quadrilaterals is that quadrilaterals do not always form planar faces. A method to generate and apply quadrilateral meshing on free form surfaces is introduced in this study where pre-deformed (non-planar) quadrilateral panels are proposed to be used at high curvature areas of the complex surface where planar meshing is not possible. In this study, structural tests and simulations are conducted on quadrilateral panels to find out the limits of surface curvature allowed for specific materials. The analyses demonstrate the behavior of quadrilateral panels under uniform wind load, pre-deformation load and finally a combined load case, which considers wind load on pre-deformed panels. The behavior of quadrilateral panels under pre-deformation is observed, and the relationship between this pre-deformation amount and the related structural and geometric design parameters, such as panel size, thickness, and material properties is investigated. The limiting curvature value for any design then can be determined using these relationships. The results of the study also demonstrate that this pre-deformation acts as pre-tensioning that increases the capacity of the panels to carry more with less deflection.
Life of the Lab: Creating Collaborative Workspaces for Scientists
by Tara Dell
A new generation of research laboratories have entered the academic community. These laboratories have physically co-located several scientific disciplines with the goal of encouraging interdisciplinary interaction, fostering new ideas and laying the groundwork for potential innovation. The purpose of this study is to investigate the relationship between use patterns/social behaviors (for the purpose of this study, social behaviors are defined to survey participants as those that involve physical presence, not interactions via email, text, IM, etc.) and the architectural design of these academic laboratories. The primary question examined is how the design and layout of space influence interaction and collaboration of the occupants. Other related questions arise in this investigation such as how the design and layout influences workspace satisfaction as well as how other workplace design aspects influence the interaction and collaboration of its occupants. The Life Sciences Institute (LSI) at the University of Michigan and the Natural Sciences Building (NSB) at the University of California, San Diego were used as case studies to explore this issue. The LSI and NSB, both completed in 2003, were designed to enhance interdisciplinary collaboration. The buildings house several different science disciplines and also include such design features as open lab spaces, shared equipment, as well as shared group spaces (i.e. conference rooms, break areas). The study focuses on the design characteristics of these two academic science buildings and the interaction and collaboration behaviors of the employees. Multiple methods of data collection are applied to understand these interrelationships. Space Syntax Analysis was used to explore the spatial layout and provide quantitative data explaining the interrelationship among spaces. Several methods were used to gather data regarding interaction within the environment: observations, surveys, and interviews. Social Network Analysis is used to understand the social connections between people working in the building. Collaborative information was obtained from the interviews and Social Network Analysis. Employees' perceptions and satisfaction with their jobs and the workspace were explored through survey questionnaires. The research provides an understanding of the spatial layout properties of each building as well as the interaction and movement patterns of employees. The data shows an association between both the connectivity and integration of spaces with interaction levels. The more integrated spaces show an increased level of movement and the occupants' job role plays a significant part in their interaction and collaboration. The research contributes to an understanding of the interrelationships between workplace design, employee perceptions, interaction patterns and collaboration. Conclusions are drawn from the results to offer suggestions for the design of future collaborative academic laboratories.
Characterizing the Audibility of Sound Field with Diffusion in Architectural Spaces
by Sentagi Sesotya Utami
The significance of diffusion control in room acoustics is that it attempts to avoid echoes by dispersing reflections while removing less valuable sound energy. Some applications place emphasis on the enhancement of late reflections to promote a sense of envelopment, and on methods required to measure the performance of diffusers. What still remains unclear is the impact of diffusion on the audibility quality due to the geometric arrangement of architectural elements. The objective of this research is to characterize the audibility of the sound field with diffusion in architectural space. In order to address this objective, an approach utilizing various methods and new techniques relevant to room acoustics standards was applied. An array of microphones based on beam forming (i.e., an acoustic camera) was utilized for field measurements in a recording studio, classrooms, auditoriums, concert halls and sport arenas. Given the ability to combine a visual image with acoustical data, the impulse responses measured were analyzed to identify the impact of diffusive surfaces on the early, late, and reverberant sound fields. The effects of the room geometry and the proportions of the diffusive and absorptive surfaces were observed by utilizing geometrical room acoustics simulations. The degree of diffuseness in each space was measured by coherences from different measurement positions along with the acoustical conditions predicted by well-known objective parameters such as T30, EDT, C80, and C50. Noticeable differences of the auditory experience were investigated by utilizing computer-based survey techniques, including the use of an immersive virtual environment system, given the current software auralization capabilities. The results based on statistical analysis demonstrate the users' ability to localize the sound and to distinguish the intensity, clarity, and reverberation created within the virtual environment. Impact of architectural elements in diffusion control is evaluated by the design variable interaction, objectively and subjectively. Effectiveness of the diffusive surfaces is determined by the echo reduction and the sense of complete immersion in a given room acoustics volume. Application of such methodology at various stages of design provides the ability to create a better auditory experience by the users. The results based on the cases studied have contributed to the development of new acoustical treatment based on the diffusion characteristics.
Energy Efficiency Design Strategies for Buildings with Grid-Connected Photovoltaic Systems.
by Chanikarn Yimprayoon
The building sector in the United States represents more than 40% of the nation's energy consumption. Energy efficiency design strategies and renewable energy are keys to reduce building energy demand. Grid-connected photovoltaic (PV) systems installed on buildings have been the fastest growing market in the PV industry. This growth poses challenges for buildings qualified to serve in this market sector. Electricity produced from solar energy is intermittent. Matching building electricity demand with PV output can increase PV system efficiency. Through experimental methods and case studies, computer simulations were used to investigate the priorities of energy efficiency design strategies that decreased electricity demand while producing load profiles matching with unique output profiles from PV. Three building types (residential, commercial, and industrial) of varying sizes and use patterns located in 16 climate zones were modeled according to ASHRAE 90.1 requirements. Buildings were analyzed individually and as a group. Complying with ASHRAE energy standards can reduce annual electricity consumption at least 13%. With energy efficiency design strategies, the reduction could reach up to 65%, making it possible for PV systems to meet reduced demands in residential and industrial buildings. The peak electricity demand reduction could be up to 71% with integration of strategies and PV. Reducing lighting power density was the best single strategy with high overall performances. Combined strategies such as zero energy building are also recommended. Electricity consumption reductions are the sum of the reductions from strategies and PV output. However, peak electricity reductions were less than their sum because they reduced peak at different times. The potential of grid stress reduction is significant. Investment incentives from government and utilities are necessary. The PV system sizes on net metering interconnection should not be limited by legislation existing in some states. Data from this study provides insight of impacts from applying energy efficiency design strategies in buildings with grid-connected PV systems. With the current transition from traditional electric grids to future smart grids, this information plus large database of various building conditions allow possible investigations needed by governments or utilities in large scale communities for implementing various measures and policies.
Urban Housing Redevelopment: An Analysis of the Perception of Vitality in Apartment Neighborhood Redevelopment in Korea.
by Youngchul Kim
This study aims to explore residential preferences, satisfaction, and use patterns in a set of case-studies of apartment neighborhoods in Korea. For this, the case-study method is applied with combined research strategies to examine four cases of apartment neighborhood redevelopment in Korea, namely Weolgok R, Gongdeok R, Jangan H, and Yeoksam E apartment estates. This research employs Canter’s place model for organizing a data collection framework to understand the perception of vitality in Korean apartment neighborhoods. The research approach focuses on three elements of Canter’s place model: physical attributes, activities, and meanings. Exploring residents’ perceptions of place vitality, this study reveals that the four examples of Korean apartment redevelopment projects demonstrate increase of physical accessibility and exposure. However, although those four have possibility to be spatially integrated around these neighborhoods, the redevelopment results demonstrate enhancement of segregation from other neighborhoods nearby. In addition, places with vitality are perceived when places inside and outside the redeveloped estates are integrated and exposed, and when people frequent places. However, these perceptions show conflicts of enclosure and exposure and hierarchy of places inside and outside the estates. Accordingly, creating places with vitality is associated with (a) considering integration and exposure of physical place conditions, (b) considering the link between people’s daily experiences and these physical places, (c) balancing boundary conditions around redeveloped neighborhoods. Differentiated, privatized, and semi-gated apartment-dominant context is the model of Korean apartment redevelopment. Findings in the four examples of Korean apartment redevelopment projects indicate that they have integrated spatial configuration inside, yet generate segregation of these apartment neighborhoods from other neighborhoods. Since everyday life is important in and to place vitality, the current method of apartment-dominant neighborhoods needs reconsideration of, indeed promotion of, daily experiences and balance of boundary conflicts in urban housing redevelopment.
Building Siwilai : Transformation of Architecture and Architectural Practice in Siam during the Reign of Rama V, 1868 - 1910
by Pirasri Povatong
This dissertation examines the process through which siwilai–Siamese aristocrats’ conception of civilization–gradually evolved from the mid-nineteenth century to the turn of the twentieth century, as evidenced in parallel transformations in architecture and architectural practice in Siam. During the reign of Rama V, Siamese aristocrats took Europe and their colonies in South and Southeast Asia as the new paradigm of “civilization,” even though the kingdom of Siam was not formally colonized. The construction of siwilai was transcultural since ideas, architectural forms, architectural practice, and even architects, had been transferred and localized in the Siamese setting. Through architecture and urban design, Siamese aristocrats fabricated the public image of not only themselves, but also the kingdom–an independent Oriental nation that was steeped in history yet engaged with enlightened modern internationalism. Late-nineteenth century Siamese architecture was unambiguously syncretic; indigenous and foreign architectural forms and spatial practices were juxtaposed, pastiched, and fused into new cultural forms that defied easy binaries like traditional/modern, Siamese/European, civilized/uncivilized. Furthermore, the dissertation examines how all of this was made possible by the transformation of the architectural practice. During the first half of Rama V’s reign, the Siamese royal master builders gradually gave way to the European builder-contractors, who, in turn, paved the way for the 1889 establishment of the Public Works Department as the institutional means to centralize construction activities. Through the entire period, collaboration between Siamese and Europeans were crucial to the production of hybridized architecture, at the service of the Siamese aristocrat.
A METHOD TOWARDS DEVELOPING AN ENVIRONMENTAL PROFILING FOR OFFICE BUILDINGS USING LIFE CYCLE ASSESSMENT (LCA)
by Ashraf Ragheb
In the last two decades, architects and designers have tried to minimize the impacts their buildings have on the environment. Although many architects claim their buildings to be sustainable, unless an objective Life Cycle Analysis (LCA) is conducted, it is difficult to evaluate the total impact that a particular building has on its surrounding environment. The theoretical foundation of the proposed framework consists of two major parts. These are the concepts of environmental sustainability and building environmental assessment. The purpose of this study is to quantify and compare the potential environmental impacts caused by three office buildings throughout their entire life cycle, from extraction of raw materials to disposal of waste. The study also demonstrates how LCA could be applied from a single material to complex systems such as buildings. It highlights the difficulties in modeling a building over a long service life (60 years) and its implications on the design process. To achieve the study objectives, a multiple case study method has been used with the LCA to determine which life cycle phase (manufacturing of materials, construction, use, maintenance, demolition) contribute the most to the total impacts. The study also identifies how building’s key assembly systems (foundations, columns/beams, walls, floors, roofs) influence its environmental impacts during its service life. Three recently-built typical office buildings are used as cases in southeast Michigan along with a streamlined LCA approach based on an inventory of energy use, material inputs and outputs, and environmental impact assessment. Furthermore, the study performed a sensitivity analysis to evaluate the effects of possible materials changes of some of building assembly components (mainly foundations, walls and roofs assemblies) and examine the change on the total impacts during 60 years of life. The study finds that the operation (use) phase of the building has the highest impacts (90+% of total impacts) during its 60 years life cycle in the following impact categories: fossil fuel consumption, global warming potential, acidification potential, and human health respiratory effects potential. Manufacturing phase has the highest impact in the following impact categories: ozone depletion with 87% of total impact, and in eutrophication with 65% of total impact respectively. Furthermore, the study finds that walls system in all building cases has the highest contribution in the following impacts: global warming (26%), acidification (40%), smog potential (35%), and respiratory effect potential (57%). Structure (beams and columns) system has the highest contribution to fossil fuel consumption (31%) and to eutrophication (56%) categories. Roofs system has also significant impacts contribution (second to structure) to fossil fuel consumption (27%), global warming (17%), and comes second to walls contributing in smog potential (29%). Foundations system contributes the most to ozone depletion potential at 58%. Through conducting a sensitivity analysis to the results, the study also find that replacing some building materials with more environmental-friendly alternatives (mainly to foundations, walls and roofs) yields reduction in total impacts by 7%-13% in different impact categories.