Green Retrofit Research Articles

APPLICATION OF GREEN RETROFIT TECHNOLOGY: A SYSTEMATIC REVIEW

Green retrofitting is a valuable approach for upgrading existing buildings towards sustainable performances. However, the lack of knowledge about the true cost effects and potential savings of green retrofits distracts building proprietors from paying those retrofits. Therefore, the current study reviewed fourteen studies available in the extant literature and identified twenty-eight different green retrofits incorporated into various buildings with their cost effects and saving potentials through a subsequent desktop study. The results indicated that the majority of green retrofits offer savings related to energy consumption, CO2 emissions, cooling load, and operating costs. Moreover, energy-saving lighting modifications are widely done in most buildings, while solar collectors, photovoltaics, and low-emission double glazing are used less often due to the long payback period and increased cost of implementation. Alternatively, the use of retrofits with lower costs and high savings, like BMS, lighting controllers, and boiler efficiency improvements, offsets the above setbacks. Furthermore, the highlighted retrofits include green roofing, bicycle parks, CO2 sensors, and air tightening retrofits, which also save energy. Rainwater harvesting absorbs carbon dioxide and runoff water, where implementing subsystem-level water meters, appliances with low flow rates, and greywater recycling save and recycle the portable water. Accordingly, the study promotes the effective implementation of green retrofits in future buildings.

Achieving to a low carbon-energy commercial building in the hot-dry climate area

ABSTRACT The main source of building energy consumption in Iran is fossil fuels. The building sector, as a result, is responsible for a high share of CO2 emissions in this country. To address the issue, the government has recently adopted the “green management system” policy in order to alleviate the severe rate of CO2 emissions from the government buildings. As a commitment to the policy, the University of Tehran plans to transform into the first green university of Iran through green retrofitting in the coming years. As the first step to the retrofitting process, this paper measures the potential of energy-saving and CO2 emission reduction in the University of Tehran Science & Technology Park (UTSTP) offices with the use of Building Information Modeling (BIM). For this, Building No. 2 of UTSTP is modeled in the environment of DesignBuilder software to provide a calibrated computational model for energy and carbon audit. A detailed audit is then conducted using the calibrated model to identify the major areas of energy loss in the case study. Based on the audit results, several green strategies are then proposed to improve the weak performance of building in the identified areas. The strategies include triple glazing windows, aerogel envelope, phase change material (PCM) insulation, and Trombe wall. Findings suggest that the thermal loss from the building structure as a result of insufficient levels of insulation in the building components is the main source of energy loss in the building. Simulation results show that green strategies to a large extent have good energy-saving and mitigation potential. Full implementation of the proposed green strategies would reduce the annual heating needs and CO2 emissions of the case study by 51.6% and 5.39% respectively.

The value effects of green retrofits

PurposeThis paper aims to decompose the value effects of green retrofits on commercial real estate. The paper disentangles various sources of value capture mechanisms that can be attained through green retrofit actions and profiles the extent to which green retrofit solutions can be effectively capitalised using transaction evidence from the Munich housing market. The insights offered can help real estate owners and investors during their ex ante analysis of future energetic retrofit investments.Design/methodology/approachThe authors offer their reader both a conceptual framework and the results from an empirical analysis to identify the value effects of retrofits and the associating gains in energy efficiency. The conceptual framework theorises the different value components that a deep retrofit has to offer. The regression analysis includes a multivariate analysis of 8,928 dwellings in the Munich residential real estate market.FindingsThis study’s framework disentangles the total retrofit value effect into three components: the capitalisation of energy savings, the exposure to the value discount because of stricter standards and the value uplift because of indirect benefits (health, employee satisfaction, marketing etc.). The regression results indicate that the value gains because of energy efficiency improvements are in the range of 2.4–7.4%, while the indirect benefits and reduced exposure to stricter standards amount to another 3%.Originality/valueWhile numerous studies have investigated the upside value effects of energy efficiency in the real estate sector, there is scant academic research which has sought to evidence the value of green retrofit solutions and the extent to which this can be capitalised. Instrumentalising the various value effects of energetic retrofit that have been identified is not straightforward. At the same time, inadequate value capture of energetic retrofit effects could delay intervention timelines or aborting of proposed retrofit actions which should be of primary concern to policymakers and stakeholders tasked with the decarbonisation of real estate assets.

Risk in Green Retrofits Projects: A Preliminary Study on Energy Efficiency

A green building has generally been adopted as one of the most effective strategies towards sustainable development in many countries which is vital in order to create sustainable environment. Despite the benefits of green retrofit to the sustainable environment, there are still retrofitted building is performed below expectation during planning stage which eventually rising operation cost. Although energy efficiency study is over emphasize in green building field, little attention has been paid off to examine the crucial phases in pre-construction stages for green retrofit and a risk that bring energy deficiency. Therefore, the aim of this research is explore a risk that influencing energy efficiency in each phases of pre-construction stage for green retrofit towards commercial building in Malaysia. The study is further support by interview sessions that has been carried out with five retrofit architects that actively involved in construction of commercial buildings in Malaysia. Based on the interviews, the risk in pre-construction stage is crucial to be assessed to minimizing energy deficiency in retrofit project. The findings of the study may useful for design consultant to deliver retrofitting project towards achieving feasible energy efficiency building.

Green Systems Integrated to the Building Envelope: Strategies and Technical Solution for the Italian Case

Green roofs and green and living walls are increasingly seen in cities, because they are an important strategy that addresses some key urban environmental issues and allows the achievement of different benefits. Among these, the most relevant ones are reduction of the “Urban Heat Island” effect, of rainfall contributions to the sewer system, of environmental impact and energy saving, and retention of harmful substance. The study aims to analyze different systems of greenery systems integrated (GSI), green roofs (GR), and green and living walls (GW-LW), as a possible retrofit technique of the envelope of heritage buildings and especially their applications in the context of historic cities in Italy, pointing out positive and negative aspects. Particularly, it pays attention to the green retrofitting of buildings and to the technical problems related to the installation of systems, since at the moment there are already several studies that show the environmental and microclimatic benefits of the integration of vegetation in architecture. This study tries to highlight the series of design procedures necessary both in the preliminary phase and then in the executive phase to relate the GSI to the existing building envelopes. The GR, from the results of the simulations conducted, demonstrate a greater simplicity in their construction, with improvements also from the point of view of the working loads on the existing structures, since the interventions are performed more easily than those on the facade. The study highlights the architectural needs that are not always considered such as the increase in the thickness of the roof and the related need to raise its edges, changing the perspective of the building. On the other hand, the GW and the LW show some complexity in their construction because they must deal with facades often rich in decorative elements and where openings affect the assemblage and connection works such as the tinsmiths of the intrados of the openings. It must be taken into consideration the necessity of having to drill masonry, often inhomogeneous, to connect fixings and the problems of stability this entails must be carefully analyzed.

Towards a sustainability assessment model for affordable housing projects: the perspective of professionals in Ghana

PurposeThis paper presents a sustainability assessment model to holistically guide sustainable construction and green retrofitting of affordable housing from the Ghanaian perspective.Design/methodology/approachA comprehensive review was carried out, which yielded 16 sustainability indicators. Then, a questionnaire survey was conducted among respondents in the Ghanaian housing sector. Forty-seven valid responses were received and analysed using fuzzy synthetic evaluation (FSE) technique.FindingsA four-index model was developed that includes: Housing and Transportation (H + T) index, household-satisfaction index, efficient stakeholder-management index and quality-related index. These indices account for 25.3%, 26.3%, 23.6% and 24.9% of sustainability attainment in affordable housing, respectively. Accordingly, household-satisfaction has the greatest contribution to sustainability attainment in affordable housing.Research limitations/implicationsDue to challenges in obtaining responses to the questionnaire, the study was conducted with relatively small number of responses.Originality/valueThe model serves as a tool that could be used to objectively and comprehensively assess sustainability performance in affordable housing. Besides, it could be used as a baseline to calibrate future projects and for benchmarking success levels of comparable housing projects. Finally, the estimated indices are applicable in decision making for optimum resource allocation for sustainable low-cost housing in the Ghanaian perspective.

Building green retrofit in China: Policies, barriers and recommendations

Green retrofit is an effective way of improving the performance of existing buildings to achieve low energy consumption and low carbon emission. To realize a successful building green retrofit, it is important to understand the barriers and to develop relevant policies for retrofitting existing buildings, especially in developing countries. As a typical developing country, China has a large number of aged buildings with high green retrofit potential. In terms of its government structure, economic development, and building stocks, China is unique in that it poses a unique set of barriers and policy strategies on the promotion of building green retrofit. Based on a critical review, existing retrofit policies in China were reviewed. Then, the barriers to building green retrofit within the context of China were identified. Based on the study of existing policies and barriers, relevant policies for addressing these barriers are recommended. The findings provide a valuable reference for policy makers in China to review current building green retrofit policies or to develop new policies that address the barriers. This study also provides a useful reference for other countries aiming to review their building green retrofit policies.

The role of facilities management in green retrofit of existing buildings in the United Arab Emirates

Purpose Green retrofitting is acknowledged as an essential strategy toward achieving long-term sustainability in the built environment. To implement this strategy successfully, the role of facility managers cannot be ignored. The purpose of this paper is to investigate present practices that are used in managing the existing facilities, to highlight the elements that govern the process of green retrofitting, and discuss the efforts and contribution of facility managers in enhancing the environmental performance of the existing facilities stock in the United Arab Emirates (UAE). Design/methodology/approach This study suggests that an adequate level of awareness of the benefits of green retrofit amongst owners and decision-makers is mostly dependent on facilities management (FM) professionals, who must establish effective communication channel with senior management. FM professionals in the UAE are well equipped and competent in greening existing buildings and can simultaneously lead a building to the path of achieving green building certification. Findings To examine the role of FM in a green retrofit and its current status in the UAE built environment, a two-step qualitative method was adopted. The study started by conducting semi-structured interviews with FM professionals and then assessing the insights obtained from the interviews against an actual case study of a LEED Existing Building certified facility. Research limitations/implications Interviews were limited to FM professionals in the private sector and the results from one case study should be considered cautiously. Originality/value This paper emphasizes the primordial role of FM professionals in promoting green retrofit in the UAE.

Examining Risk as Guideline in Design Stage for Green Retrofits Projects: A Review

Green buildings have generally been adopted as strategy towards sustainable development to reduce greenhouse gas. The implementation of green concept recently has widely spread over the year. However, the positive impact to the environment is still low due to heavily focus on new construction project as compare with retrofitting the existing building. A retrofit practice is not only regaining overall existing building appearance, but the improvement towards energy efficiency is remarkably significant at the expense of huge challenges and risk. As a consequence, retrofit practitioner is confronting an assortment of risks at the early stage of the project. Given that, green retrofit concept is emerging research area to Malaysia construction industry which motivates to determining the risk involve in design stage. This paper aims to review risk in design stage for green retrofit project for commercial buildings through gathering comprehensive literature review. As a result, two main category risks in design stage (technical/quality risk and financial management risk) is determined and extracted to identify risk. These risks are then quantified through analysis to enhance design performance within cost- benefit. The proposed conceptual framework model is expected to assist retrofit practitioner to identify risk and obtain feasible retrofit strategy.

Urging Green Retrofits of Building Façades in the Tropics: A Review and Research Agenda

Urging Green Retrofits of Building Façades in the Tropics: A Review and Research Agenda

China's policies of building green retrofit: A state-of-the-art overview

Green retrofit in existing buildings is of great significance in achieving a sustainable environment. Various policies have been introduced around the world to promote building green retrofit, whereas the uptake is rare for policy ineffectiveness. To improve policy effectiveness, it has been emphasized that a systematic review of existing retrofit policies has a key priority. In this study, a comprehensive review on retrofit policies in China was conducted because there are great application potential for green retrofit in China's existing buildings. This study examined the state-of-the-art development of retrofit policies during 1996–2019 and explored policy characteristics based on content analysis. The ambitious retrofit objectives and multiple retrofit instruments were identified. The relevant policy instruments can be grouped into six categories, including command and control, economic incentives, technology, information, certification, organization & professional. The most cited policy was the command and control instrument, followed by the certification-based instrument. Moreover, policy instruments related to economic incentives, technology and information were also valued by the China government, while the government attempted to reduce the adoption of economic incentives and technology measures since 2010. In addition, organization & professional instruments are largely ignored in China. In the light of these findings, a roadmap was proposed to enhance the effectiveness of building retrofit policies. This study sheds lights on the effectiveness of China's building policies to accelerate the popularity of green retrofit, and provides valuable references for other countries and regions to shape their own policy pathways towards the large-scale promotion of building green retrofit.

Development and Application of Evaluation Index System and Model for Existing Building Green-Retrofitting

This paper establishes an evaluation index system for existing building green-retrofitting considering different building majors. The weights of indicators at different levels were determined by using decision-making analytic hierarchy process. According to fuzzy mathematics theory, indicators at different levels were taken into an evaluation factor set while three-star level, two-star level, one-star level and unqualified level were taken as the comment set to develop a fuzzy comprehensive evaluation model for the green retrofitting of existing buildings. Additionally, the evaluation system proposed by this paper and the national standard “Assessment standard for green building” GB/T 50378-2014 were used in the assessment of a certain office after green retrofitting as a case study. The case study indicates that the evaluation developed by this research are more applicable for green retrofitting of existing building, while the national standard “Assessment standard for green building” has limitations except for new building.

Factors Influencing Residents’ Intention toward Green Retrofitting of Existing Residential Buildings

The green retrofitting of existing residential buildings is an important approach to realise the sustainable development of stock buildings. In addition to the new technologies and materials related to green retrofitting, the intention of residents toward the green retrofitting of existing residential buildings must be understood. However, the factors affecting such intentions are still unclear. Hence, this study refers to the extended theory of planed behaviour and constructs a theoretical model of the intention toward the green retrofitting of existing residential buildings. On the basis of the data from 507 questionnaires collected from eastern and western China, the theoretical model is tested via structural equation modelling (SEM). Multigroup SEM is used to analyse the differences in population characteristics and the intention of residents toward the green retrofitting of existing residential buildings in residential areas. Research results reveal the following: (1) the most important factors affecting residents’ intention toward green retrofitting are policy factors, followed by cognition of green retrofitting, behaviour, subjective norms, and perceived behavioural control; (2) policy factors not only directly affect residents’ intention toward green retrofitting but also indirectly affect their intention toward existing residential green retrofitting through perceived behavioural control; (3) residents’ cognition of green retrofitting exerts no significant direct impact on their intention toward green retrofitting, but it does indirectly affect their intention toward green retrofitting through behaviour and subjective norms; (4) behaviour, subjective norms, and perceived behavioural control have direct and significant influences on intention toward green retrofitting; (5) demographic characteristics (gender, age, monthly family income, education level, and occupation) and regional variables (east and west) present significant differences in different influence paths. The conclusion of the study provides a targeted path reference for the promotion of the green retrofitting of existing residential buildings.

The Potential of Greenable Area in the Urban Building Stock

In the context of establishing green infrastructure in cities, urban retrofit has presumably larger area potential than ground-based green. To support the large-scale advancement of urban green, the assessment of greenable potential plots in the building stock, both on horizontal and on vertical scale, provides first indispensable indications for decision-making. However, reliable and solid data to the state of the buildings is currently not available. The research study Urbane GmbA explored a new methodological approach, based on publicly available geo-data, and applied it at two study sites in high-density urban quarters in Vienna. The combination of a GIS-based analysis with digital and on-site photos allowed for the creation of a Level of Detail 2 (LOD2) 3D-model and subsequently the estimation of the green retrofit potential of roofs and facades. Comprehensive maps with the data of the 2D building footprints provide valuable information for planners, including building characteristics and greenable area potential. The approach proved to provide more comprehensive information including building characteristics fundamental to the planning and decision-making process. The achieved results are merged with an evaluation matrix generated for attributing available facade and roof greening systems. This allows for more focused decision support for the retrofit of the building stock towards more sustainable and resilient district development.

Low Cost Green Retrofit for Office

Building retrofit programme has received significant attention in recent years. This article aims to make a contribution towards low cost green retrofit for office application. The retrofit options suggested in this study includes ventilation system, efficient lighting system, potted plants for better indoor air quality and thermal insulation to walls and roof. The detailed analysis of proposed ventilation system is included in the present study. The comparison between proposed ventilation system with existing air conditioning system is also analyzed. The study demonstrates an efficient way towards achieving low cost green retrofit. The outcomes of this case study will increase the confidence among stakeholders in promoting energy conservation and sustainability.

Case-based reasoning approach for supporting building green retrofit decisions

Building green retrofit is considered as an effective means of energy saving and achieving sustainable development goals. The success of a building retrofit is highly dependent on the retrofit strategies used. However, it remains challenging to select appropriate retrofit strategies for a specific retrofit building. There are numerous cases of building retrofit around the world, which can be collected, stored, and analysed. The knowledge gained from these cases could provide a useful reference for making decisions on new retrofitting projects. This study presents a case-based reasoning (CBR) approach to support building green retrofit decisions. A total of 71 retrofit cases in China were collected. The attributes of the retrofitting buildings were identified, including the general building information, component information, and energy and cost information. A synthetic optimisation weighting method was adopted based on both expert opinion and the attribute characteristics. A real retrofit case located in Shanghai was used as a case study to demonstrate the application of the CBR approach. The results indicate that the CBR approach can aid in identifying similar cases from the case database, and extracting valuable information from these. The experience and lessons learned from past cases can guide decision makers in making improved decisions on new green retrofit projects.

Incentives for green retrofits: An evolutionary game analysis on Public-Private-Partnership reconstruction of buildings

To solve the problems of existing buildings with high energy consumption, the government has organized for private sectors to implement green retrofits for the Public-Private-Partnership reconstruction of buildings (PPP-BR). However, most private sectors are reluctant to implement green retrofits because of high costs, low benefits and long payback periods. The existing literature analyzed PPP-BR projects, barriers and incentives of green retrofits. However, it does not provide any quantitative method to illustrate the effectiveness of incentives and the strategy changes of investment groups. To fill this gap, this paper reveals the game strategy change of encouraging green retrofits and implementing green retrofits in government groups and investment groups through an evolutionary game analysis. On this basis, the case simulation method is used to change the parameters to analyze the incentive effectiveness and the strategy change of green retrofitting by investment groups. It can be found that the final evolutionary game results will take on two forms: first, the government groups encourage green retrofits, and the investment groups implement green retrofits; second, the government groups do not encourage green retrofits, and the investment groups do not implement green retrofits, respectively. When the government groups highly encourage green retrofits, the investment groups will also increase its willingness to implement green retrofits. The simulation results show that reducing costs and increasing benefits will promote green retrofits; however, this incentive measure will be limited by objective conditions. Comparatively speaking, the policy incentive measures are less affected by an objective environment, but positive policy incentive measures will get negative effects. In contrast, negative policy incentive measures that may cause problems will be most effective. Therefore, the combination of positive and negative policy incentive measures will be the better and more moderate way to promote green retrofits for PPP-BR.

Attaining sustainability in built environment: Review of green retrofit measures for existing buildings

Building retrofit is a critical measure for achieving sustainability in architecture and built environment. It adopts the use of a variety of retrofit technologies to enhance building energy performance at a beneficial cost-effectiveness. This may include certain approaches of building envelope improvement, mechanical systems improvement etc., while keeping the building indoor environment comfortable for human. Besides retrofitting of building envelope and the mechanical system, the improvement of operating and management practices should also be considered for whole general improvements. Therefore, this paper presents a brief overview of previous studies on retrofit measures, its application, performance evaluation and related challenges on a variety of buildings are provided. Furthermore, it defines an average mix of retrofit measures and ranks the related challenges for various building typologies. The objective of this study is to lay a foundation for building researchers, practitioners and decision-makers to effectively evaluate retrofit measures for achieving sustainable building performance globally.

Post-evaluation of energy consumption of the green retrofit building

Retrofitting of existing buildings plays a critical role to achieve sustainable development. This is considered as one of approaches to achieving sustainability in the built environment. In order to evaluate energy consumption of the existing building which had transformed into green building, this article takes the green office building as an example, which located in the summer hot and cold winter zone in China. Collecting the building energy consumption from 2014 to 2016, analyzing energy saving effects by comparing with the standard for energy consumption of building (GB/T 51161-2016) and other cases.Results showed that energy consumption of the case building decreased from 728 MWh to 633 MWh year by year. According to the correction formula in the standard, the corrected value Eoc=72.12 kWh/ (m2·a) is lower than upper limit (85 kWh/ (m2·a)) but higher than target value (70 kWh/ (m2·a)). Therefore, there is large energy conservation potential in air conditioning system and lighting.By comparing with the energy consumption of green commercial buildings in other countries, the result indicates the energy consumption is one-third of the foreign green commercial buildings.the paper provides a reference for the actual operation energy consumption of retrofitting of existing buildings in this area.

Parametric simulation study for green roof retrofit over high performance solar house prototype “EFdeN Signature”

The advantages of green roofs are well documented, ranging from heat island reduction, thermal comfort, air quality, stormwater management and energy savings for buildings. However, it has been shown that green roof retrofits are more effective in old, low efficiency buildings. This paper studies the possibility of retrofitting a high efficiency solar house with a green roof system being partially shaded, optimising its characteristics by means of parametric simulation. The input variables of the green roof system are: growth medium thickness, LAI (leaf area index) and height of plants. The output variables by which the different green roof systems are compared are: annual energy demand for heating and for cooling. The study concluded that the average reductions of energy consumption when retrofitting an efficient building with an extensive green roof are of 1.01% for heating and 4.61% for cooling, but optimising parameters (low LAI in winter, high LAI and height of plants in summer) can get reductions to 1.55% for cooling and 5.95% for cooling.