Integrated performance framework to guide facade retrofit

The façade retrofit market faces some key barriers: the selection of performance criteria and the reliability of the performance data. On the demand side, the problem is approached from an investment perspective which creates "split incentives" between the stakeholders who pay for the investment and those who benefit from it. On the supply side, there is an inherent complexity in modeling these options because of the incomplete knowledge of the physical and cost parameters involved in the performance evaluation. The thermal comfort of the building occupant is an important component of the retrofit performance assessment. This research attempts to fill a gap in the approach to façade retrofit decision by 1) quantifying uncertainties in these three dimensions of performance, 2) incorporating new financing models available in the retrofit market, 3) considering the target and risk attitude of the decision maker. The methodology proposed in this research integrates key indicators for delivery process, environmental performance, and investment performance. The purpose is to provide a methodological framework for performance evaluation. A residential case study is conducted to test the proposed framework. Three retrofit scenarios including the financing structure are examined. Each façade retrofit scenario is then evaluated based on the level of confidence to meet or exceed a specific target improvement for the Net Present Value and the risk to fall below a minimum improvement threshold. The case study results confirm that risk must be considered for more reliable façade retrofit decision-making. Research findings point to further research needed to expand the understanding of the interdependencies among uncertain parameters.PhDCommittee Chair: Augenbroe, Godfried; Committee Chair: De Wilde, Pieter; Committee Member: Aksamija, Ajla; Committee Member: Brown, Jason; Committee Member: Eastman, Charle

A system for the management of old building retrofit projects in historical centres: the case of Portugal

The retrofitting works in old buildings require appropriate knowledge of the vernacular techniques. Previous researches have identified retrofitting works as more intrusive and using more unnecessary demolition materials than real needs. This study constitutes a new framework that focuses on the project management success of old building retrofitting in historical centres by developing a methodological system for this purpose. It uses a construction sector system approach, reviews legal requirements, framework specifications, recommendation practices and sustainable measures adapted to old building projects. It presents 50 parameters adapted to these works’ specificities that could be used by construction market stakeholders. The research uses a case study methodology divided in two parts. The first one involves the review of building retrofitting projects in historical centres, complemented by a questionnaire in the second part. The results of the projects review have shown little concern with the underlying sustainability aspects of retrofitting works in all project designs analysed. However, the questionnaire results have revealed a high interest and applicability of all parameters omitted in the project designs data. The study describes a useful management system in a toolkit format which might contribute to reduce uncertainty in the management of retrofitting projects in historical centres.info:eu-repo/semantics/publishedVersio

A Multi-criteria Framework for Decision Process in Retrofit Optioneering through Interactive Data Flow

Aim of this research is to deliver a system of procedures and instruments that allows comparing different scenarios of restoration and retrofit of existing buildings applicable each time a relevant decision about the asset has to be made. The system developed takes advantages of Building Information Modeling (BIM) and Analytical Hierarchy Process (AHP), thus to focus on main clients’ needs. Decisions about real estate assets are frequently made by managers with incomplete and scattered data, not sufficient to fully support the decision making process. Using a BIM model as a central repository of information could strongly support to compare objectively different scenarios and consequently to decide the application of a multi-criteria matrix involving management, energy, economic and social issues. BIM and BEM (Building Energy Modelling) techniques have a wide potential and analysis capabilities; however, they are often adopted without an integrated framework, causing missing performances and costs overrun. The result is a system enabling to analyze the asset, to produce BIM and BEM models ready to include life cycle data, to evaluate feasible alternatives and scenarios and to extract relevant performance indicators for decision makers’ support. An existing office building in Milan representing an awkward field for intervention is the case study for the system application. While the tools and software adopted are commonly used, the system of procedures developed by the authors can be considered as an ensemble of workflows otherwise typically used independently. Using them together enhance the decision process providing data on which to set up a strategic plan of the refurbishment considering costs, continuity in occupancy and energy efficiency

Transdisciplinarity in energy retrofit: A conceptual framework

This study explores the role of Energy Retrofit (ER) in Low Carbon Transition (LCT). The literature recognises the need to move towards a transdisciplinary approach in ER, which encompasses multidisciplinarity and interdisciplinarity. However, the fragmentation between different disciplines remains a significant problem, mainly due to challenges associated with knowledge exchange across the allied disciplines that play a role in ER. The authors posit that ER projects has been conceptualised and implemented using a Systems perspective so that an integrated approach that is akin to transdisciplinarity could become commonplace. Against this background, the aim of this paper is to establish to what extent ER has been conceptualised as a System in the literature so that complexities can effectively be managed through a transdisciplinary approach. This work is based on a literature review of 136 peer-reviewed journal papers. The content analysis demonstrates that current research on transdisciplinarity in ER can be conceptualised in five categories and 15 lines of research. They are presented as a Conceptual Framework, which is this paper’s main contribution to existing knowledge. It reveals the direction of innovation in ER for LCT, and is illustrated as a cognitive map. This map exposes the current fragmentation implicit in the literature, and proposes critical connections that need to be established for a transdisciplinary approach. It also shows that the discourse on LCT changed by moving beyond the building scale; and recognising the need to embrace disruptive and local technologies, and integrating the social and technical aspects of ER. Innovative technical solutions and robust information modelling approaches emerge as key vehicles towards making decisions that pay regard to the economic, social and technical factors and that empower the prosumers to play an active role in LCT

Nearly Zero Energy multi-functional Buildings - Energy and Economic evaluations

Building energy renovation is one of the pillars upon which the 2050 European low-carbon goals are based. Simultaneously, building energy renovation is widely recognized as the trump card for the new start of European economy. However, at present the renovation rate of the existing building is very low throughout Europe (approximately 1%) and investments in high performing buildings are generally mistrusted by stakeholders, due to their high capital costs. In this context, this PhD thesis dedicated its efforts to investigate from the energy and financial perspective the consequences of buildings renovation in the European scene. Particularly, the research boundaries were delineated by focusing on non-residential, multi-functional buildings, that are nowadays poorly studied due to their heterogeneous nature. In this view, the thesis’ contributions were addressed at three levels: a) multi-functional buildings as archetypes to input in energy models for long-term energy analysis; b) multi-functional buildings used to test the financial viability of energy efficiency projects, in view of reaching the nearly Zero Energy performance level. As these analyses necessarily require case studies, the attention was directed towards a specific type of multi-functional buildings, hotels; c) multi-functional buildings as test-bed to assess the impact of co-benefits on the financial performances of energy efficiency projects. Once again, hotel buildings were selected for the development of the detailed analyses. To include archetypes of multi-functional buildings in bottom-up building energy models, a new modelling method was proposed. The method provides a rationale for the classification of energy end-uses into typical and extra, so that the modeling problem is simplified and a coherent use of well-established Reference Buildings modelling methods is allowed. Then, the focus of the research was narrowed to the hotel sector, which was found to lack of reliable energy performance benchmarks and effective performance-based greens labels. Case study buildings were object of energy and financial evaluations. On one side, real hotels were analyzed to test the application of the EU imposed cost-optimal methodology as a support tool to guide private investors’ investment decisions. On the other side, an Italian Reference Hotel was modelled and the cost-optimal methodology was applied to investigate the existing energy and financial gaps between cost-optimal and Nearly Zero Energy performance level in Italy. From both perspectives, findings converged to similar conclusions: high performing retrofit are not financially viable, if avoided energy costs are the only operational benefits accounted for. Starting from these outcomes, the thesis investigated how valuation procedures could be exploited to make NZEB retrofit solutions appealing for private investors. Based on a literature review of the co-benefits of energy efficiency projects, 2 different strategies were pursued and tested on the Italian Reference Hotel. The first approach proposed to monetize co-benefits of energy efficiency interventions based on literature and to include them in the well-established cost-optimal methodology. Results highlighted that co-benefits related to the market appreciation of a retrofitted hotel can drastically change the perception of the financial convenience of an ambitious retrofit project. In the latter strategy, the issue of monetizing non-energy benefits was faced directly: a technique to value non-market goods was applied to monetize comfort. Findings proved that hotels guests’ willingness to pay for comfortable indoor conditions is higher than the hoteliers’ extra costs for providing them. Due to the context-dependent nature of co-benefits, the findings of the 2 applications do not represent generally applicable quantitative benchmarks. Nonetheless, they confirm the leading role that literature attribute to co-benefits in the success of energy efficiency projects

DECISION-MAKING FRAMEWORK FOR THE SELECTION OF SUSTAINABLE ALTERNATIVES FOR ENERGY-RETROFITS

Buildings are major consumers of energy worldwide. On the other hand, over 60% of the US housing inventory is over 30 years old and a large number of these homes are energy inefficient. Therefore, it is essential to target the existing building stock for energy efficient interventions as a key to substantially reduce the adverse impacts of buildings on the environment and economy. Building energy retrofitting has emerged as a primary strategy for reducing energy use and carbon emissions in existing buildings. An energy retrofit can be defined as a physical or operational change in a building, its energy-consuming equipment, or its occupants\u27 energy-use behavior to convert the building to a lower energy consuming facility. Energy retrofitting could result in additional sustainable benefits such as reducing maintenance costs, reducing air emissions, creating job opportunities, enhancing human health, and improving thermal comfort among others. One of the main challenges in building energy retrofitting is that several combinations of applicable energy consumption reducing measures can be considered to retrofit a building and it is a difficult task to choose the best retrofit strategy. Although numerous resources provide advice on how to retrofit a building, decisions regarding the optimal combination of retrofitting measures for a specific building are typically complex. In addition, most of the decisions for energy retrofits are based on limited cost categories rather than environmental and social considerations. The main goal of this study is to develop a decision support system that integrates sustainable criteria (i.e. economic, environmental, and social benefits) in decision-making in energy retrofits. This goal will achieved through following objectives: (1) Determining the impact of building life-cycle on energy retrofitting decision-making; (2) Identifying and quantifying the sustainable benefits of building energy retrofitting to be used as an objective function in optimization problems; (3) Developing a systematic approach to select among different sustainable decision criteria for energy retrofitting decision-making; and (4) Developing and demonstrating a decision-making optimization model to select the best energy retrofitting alternative for a specific building while maximizing its sustainable benefits. First a life-cycle cost analysis of the case study is presented in terms of energy retrofitting. This life-cycle cost analysis is used to explore the process of decision-making in energy retrofits. Then, a comprehensive study on identifying and quantifying the sustainable benefits of energy retrofits is performed that can be used in decision-making. Different tools such as literature review, surveys, Delphi technique, concept mapping approach, hedonic price modeling, and statistical analysis are used in this step. After that, a Sustainable Energy Retrofit (SER) decision support system is proposed. Finally, the application of this decision support system on a case study of a house located in Albuquerque, New Mexico is explored. This research contributes to the body of knowledge by: (1) Integrating sustainable impacts of building energy retrofits (i.e. Economic, Environmental, and social) in decision-making; (2) Proposing a decision matrix that guides decision-makers on how to select the objective function(s) to formulate an optimization problem that results in the selection of the best energy retrofitting strategy, considering the benefits to investors; (3) Introducing a novel simplified energy prediction method by integrating dynamic and static modeling; (4) Measuring the implicit price of energy performance improvements in the US residential housing market; (5) Identifying, categorizing, and mapping the social sustainability criteria of energy improvements in existing buildings; and last but not least (6) Developing a decision-support system for energy retrofitting projects that integrates the above approaches. The energy retrofitting decision-making model developed in this research can be implemented for different types of buildings to help decision-makers select the optimum energy retrofit strategy that not only maximizes monetary benefits, but also maximize environmental and social benefits. The presented research can also help homeowners to plan or evaluate their retrofitting strategies

Lessons Learned and Next Steps in Energy Efficiency Measurement and Attribution: Energy Savings, Net to Gross, Non-Energy Benefits, and Persistence of Energy Efficiency Behavior

This white paper examines four topics addressing evaluation, measurement, and attribution of direct and indirect effects to energy efficiency and behavioral programs: Estimates of program savings (gross); Net savings derivation through free ridership / net to gross analyses; Indirect non-energy benefits / impacts (e.g., comfort, convenience, emissions, jobs); and, Persistence of savings

A holistic multi-methodology for sustainable renovation

A review of the barriers for building renovation has revealed a lack of methodologies, which can promote sustainability objectives and assist various stakeholders during the design stage of building renovation/retrofitting projects. The purpose of this paper is to develop a Holistic Multi-methodology for Sustainable Renovation, which aims to deal with complexity of renovation projects. It provides a framework through which to involve the different stakeholders in the design process to improve group learning and group decision-making, and hence make the building renovation design process more robust and efficient. Therefore, the paper discusses the essence of multifaceted barriers in building renovation regarding cultural changes and technological/physical changes. The outcome is a proposal for a multi-methodology framework, which is developed by introducing, evaluating and mixing methods from Soft Systems Methodologies (SSM) with Multiple Criteria Decision Making (MCDM). The potential of applying the proposed methodology in renovation projects is demonstrated through a case study

Multiple Criteria Analysis of the Life Cycle of the Built Environment

To design and achieve effective the life cycle of the built environment a complex analysis of its stages as well as stakeholders, their aims and potentialities is needed. The effect of micro, meso and macro environmental factors should also be taken into account. A thorough built environment’s life cycle (brief; design; raw material extraction, transport and processing; construction materials production and distribution; construction; use, repair and maintenance; demolition; disposal, reuse, or recycling) analysis is quite difficult to undertake, because a buildings and its environment are a complex system (technical, technological, economical, social, cultural, ecological, etc.), where all sub-systems influence the total efficiency performance and where the interdependence between sub-systems play a significant role. Various stakeholders (clients, users, architects, designers, utilities engineers, economists, contractors, maintenance engineers, built environment material manufacturers, suppliers, contractors, finansing institutions, local government, state and state institutions) are involved in the life cycle of the built environment, trying to satisfy their needs and affecting its efficiency. The level of the efficiency of the life cycle of the built environment depends on a number of variables, at three levels: micro, meso and macro level. The problem is how to define an efficient built environment life cycle when a lot of various parties are involved, the alternative project versions come to hundreds thousand and the efficiency changes with the alterations in the environment conditions and the constituent parts of the process in question. Moreover, the realization of some objectives seems more rational from the economic perspective thought from the other perspectives they have various significance. Therefore, it is considered that the efficiency of a built environment life cycle depends on the rationality of its stages as well as on the ability to satisfy the needs of the stakeholders and the rational character of environment conditions. Formalized presentation of the research shows how changes in the environment and the extent to which the goals pursued by various stakeholders are satisfied cause corresponding changes in the value and utility degree of a built environment life cycle. With this in mind, it is possible to solve the problem of optimization concerning satisfaction of the needs at reasonable expenditures. This requires the analysis of the built environment life cycle versions allowing to find an optimal combination of goals pursued and finances available. References to the most modern world scientific literature sources are presented in the monograph. The monograph is prepared for the researchers, MSc and PhD students of civil engineering, construction management and real estate development. The book may be useful for other researchers, MSc and PhD students of economics, management and other specialities. The edition was recommended by the Committe of Studies of VGTU Faculty of Civil Engineering. The publication of monograph was funded by European Social Fund according to project No. VP1-2.2-ŠMM-07-K-02-060 Development and Implementation of Joint Master’s Study Programme “Sustainable Development of the Built Environment”.The edition was recommended by the Committe of Studies of VGTU Faculty of Civil Engineering. The publication of monograph was funded by European Social Fund according to project No. VP1-2.2-ŠMM-07-K-02-060 Development and Implementation of Joint Master’s Study Programme “Sustainable Development of the Built Environment”

Integrated Framework for Wildfire Risk Mitigation Planning at the Wildland/Urban Interface

Past suppression-based wildfire management practices have increased the frequency and intensity of wildfires. Advocates for the re-introduction of natural wildfire regimes must also prioritize wildfire damage protection, especially for vulnerable communities located near forests. Areas where urban and forest lands interdigitate are called the Wildland Urban Interfaces (WUIs). In the United States, the area of the WUIs is increasing, making more people vulnerable to wildfires. By responding to four research objectives, this dissertation proposed and tested an integrated framework for wildfire risk mitigation decision making at WUIs. Decision makers who could benefit from the results of this dissertation include WUI homeowners, community planners, insurance companies, and agencies that provide financial resources for managing wildfire. The first objective investigated the complex relationship between wildfire and property values in a WUI community affected by a catastrophic wildfire event. The analysis focused on evaluating whether the damage from a previous wildfire, and the risk from a potential future wildfire are negatively capitalized in the housing market of a WUI community. A Hedonic Pricing Method (HPM) was applied on homes in Los Alamos County located in Northern New Mexico. Los Alamos is the home of a highly educated and high income community which experienced the Cerro Grande fire in 2000. Results showed that wildfire damage has a negative impact on the housing price, whereas future wildfire risk is a positive driver in the Los Alamos housing market. These findings support the wildfire mitigation paradox that states that WUI homeowners tend to underinvest for mitigating wildfire risk on their properties. The second objective investigated the optimal investment required for mitigating the vulnerability of residential buildings to wildfire. The optimal retrofit plan for individual homes was estimated using an integer programming method. The evaluation function for this optimization is based on a multi-attribute vulnerability assessment system that yields a wildfire vulnerability rating for all properties in the study area. A feasible solution to this optimization problem is one that decreases the vulnerability rating of the house to an acceptable rating. Additional data included: (i) vulnerability assessment cards of the properties, (ii) building and site characteristics of the properties, and (iii) unit costs of implanting appropriate retrofit measure on each element of the property. These datasets were collected for 389 properties in Santa Fe County’s WUIs. Using an integer programing model, the total cost of reducing the vulnerability ratings from “high” and “very high” to “moderate” vulnerability level was estimated for each property. To account for uncertainties in the costs of implementing a specific retrofit measure, a Monte-Carlo sampler was used to generate 2,400 cost scenarios from cost probability distributions. Using a regression analysis on the property data, a cost function for vulnerability mitigation through retrofitting was derived. The cost function allows estimation of the retrofitting cost per area of the house and considering the initial vulnerability rating of the house. The third objective was to investigate wildfire optimal mitigation investment schedules for homeowners. Two types of investments for mitigation were analyzed, namely self-insurance and market insurance. Self-insurance is represented financially as the amount homeowners spend to implement retrofit measures to reduce their property’s vulnerability to wildfires. Market insurance is the transfer of wildfire damage liability to a third party or insurance company. The investment decision of homeowners over a multi-year investment plan considering the effects of budget and market insurance policy constraints was formulated. The effectiveness of self-insurance improvements was modeled as a damage probability function. Using a mixed-integer programming model, the optimal annual investment for market and self-insurance was estimated. The case study in this chapter demonstrated the effect of various parameters on the investment schedule of honeowners. This case study considered the time value of money and insurance companies’ contingency policies and budget constraints. The results showed that in the absence of budget constraints and mandates on mitigation, the homeowner’s optimal choice would be to fully invest on insurance and to purchase the broadest wildfire hazard insurance coverage. When a minimum mitigating retrofit effort is required by insurance companies, homeowners would invest more at the beginning of the period and decrease their investment through time. In this case results showed that a homeowner would achieve a higher expected value of investment than a homeowner with whose investments increase through time. In the fourth objective, an Agent Based Model (ABM) is proposed to account for heterogeneity in homeowners’ attributes and behaviors when confronting wildfire risk hazard. The success of the community to reduce wildfire risk was evaluated by aggregating the impact of each individual agent’s behavior. The investment behavior of each homeowner for a five-year planning period was retrieved from the optimization model proposed in the third objective. A neighborhood of six homeowners was used to test the proposed ABM. When a wildfire occurs, the wildfire may or may not damage the property. Therefore, the loss accrued by each homeowner was stochastically simulated for each year in the simulation. The probability of loss was formulated as a function of the initial vulnerability rating of the property and the homeowners’ cumulative investment on mitigation. The analyzed scenarios considered different types of homeowners (i.e. mitigating or non-mitigating). The spatial impact of neighboring properties on the loss potential of a homeowner was modeled using a conceptual fire spread model based on a Cellular Automata propagation model. Results suggest that (i) the location of the property in combination with (ii) the investment behavior of the homeowner influences the neighborhood’s aggregate loss to wildfire. Policy-makers can better mitigate aggregate loss to wildfire by prioritizing certain locations over others