Renovation Alternatives Research Articles

Toward sustainable urban energy solutions: Introducing F NeCESSCity framework for energy-saving smart city configuration

This research aims to develop a Framework Necessary for the Configuration of Energy-Saving Smart Cities (F NeCESSCity) that incorporates the essential considerations for establishing an energy-saving smart city (ESSC). F NeCESSCity encompasses: (i) a Scan-to-BIM method for the digital virtualization of existing cities, and (ii) a methodology for deriving an optimal renovation strategy at the ESSC level, considering energy performance and economic factors. The application of F NeCESSCity to real-world scenarios has demonstrated that (i) fast and reliable modeling is achievable, (ii) a broad spectrum of alternatives can be developed and assessed, and (iii) an optimal renovation strategy at the ESSC level can be identified. The use of F NeCESSCity is expected to facilitate the successful development of ESSC plans, where virtual modeling and the evaluation of renovation alternatives are realized.

Application and validation of a method to assess the energy reduction and environmental impact of renovation alternatives

The renovation of residential stock is one of the most promising areas, in terms of energy reduction, because these buildings are highly inefficient and represent the largest part of the building stock. However, the environmental impact assessment over the life cycle of building renovation is rare. It is more common to develop an assessment for new buildings. This study presents a method that combines the evaluation of the benefits of renovating residential buildings, considering cost, energy and environmental benefits using Life Cycle Assessment (LCA). The method is based on 3 stages of development. First, the database of energy certificates, costs and LCA was analysed. The second step is to develop a workflow in Rhino/Grasshopper/E-Plus to automatically model a residential building and feed the simulation model with the data obtained from the databases. Finally, a simulation campaign was carried out to obtain an optimal renovation package, minimising energy consumption and environmental impact. The research was carried out in a case study in Uddevalla, Sweden. The residential building has different measurements including energy consumption data before and after renovation. This was used to validate the proposed methodology. The validation shows that accurate results are achievable with potential for mass application.

Intelligent Multi-Criteria Decision Support for Renovation Solutions for a Building Based on Emotion Recognition by Applying the COPRAS Method and BIM Integration

With accelerating climate change and the urgent need to cut carbon emissions, global focus has turned to the existing building stock and its renovation. Sustainable renovation helps to achieve better energy performance and gain wider sustainability benefits, such as increased value of a building, improved indoor and outdoor comfort, reduced carbon emissions, and the higher satisfaction and better emotional state of inhabitants. Numerous systems and tools have been developed worldwide to assist with decision making in the choice of preferred modernisation scenarios and alternatives. However, social aspects are often neglected in the existing systems, and emotions of inhabitants are rarely analysed. To close this gap, the present study proposes an innovative decision-making framework for sustainable renovation solutions, based on emotion recognition. The framework makes it possible to assess various renovation alternatives against sustainability criteria and real-time measurements of the emotional states of inhabitants. Based on the proposed framework, an intelligent multi-criteria decision support system was developed by integrating COPRAS and the facial action coding system, the method of automatic facial expression recognition, and the continuous calibration and participant methods. The system was tested in the case study of renovation solutions for a building located in Ukraine. The research results revealed that the proposed renovation solutions had a positive impact on the emotional state of inhabitants, especially when visual materials such as drawings were presented. Some case studies were analysed together with the application of decision system tools and building information modelling (BIM) subsystem integration as a multidiscipline application of various applied sciences for representation and data analysis. The authors of this research have been analysing human emotional, affective and physiological states for many years and collected over a billion of these data in Vilnius city during the H2020 ROCK, SAVAS and BIM4REN projects. Data acquired during measurements in Vilnius were used to determine correlations and trends for the case study. The proposed methodology and findings of the study can be useful for researchers who use the evaluation and analysis of human emotions when there is a need to choose appropriate renovation measures or find alternative solutions.

Sensitivity analysis of building energy models due to the shading effect of surrounding buildings to support building renovation

Building energy simulation is an analytical process to help building owners and designers evaluate the energy performance of the building. Uncertainty in the building energy modelling influences the building renovation from two perspectives: 1) calculating as-built energy consumption, 2) analysing the energy performance of renovation alternatives. Energy models can enhance by incorporating contextual and surrounding data. To this aim, we conducted a systematic study to investigate the effect of surrounding buildings in different distances, heights, and orientations in studying the as-built energy consumption of an example building. The research also investigates the impact of a specific surrounding building on the energy performance of three different renovation alternatives, namely the modification of windows, external walls, and roofs. The results demonstrate that a higher height to distance ratio of the surrounding buildings influences the energy consumption more dramatically. In addition, a surrounding building located in the south direction causes more effect on the energy result than other directions when the building is in the northern hemisphere. For renovation scenarios, if there is a specific building in the south of the building under renovation, the window modification leads to less energy consumption than other renovation scenarios. The paper discusses that for renovation projects, an initial examination of surrounding buildings before selecting the renovation alternative is crucial; since different placements of surrounding buildings can affect the performance of renovation scenarios differently, which can cause a variation in the cost of renovation.

A multi-criteria decision-making framework for residential building renovation using pairwise comparison and TOPSIS methods

The rate at which buildings are renovated across Europe is expected to increase in the upcoming years. However, selecting renovation solutions for residential buildings is still a challenging task due to the participation of multiple stakeholders, lack of clear decision-making procedures, and diverse effects resulting from the renovation alternatives. Most of the existing approaches do not consider multiple stakeholders and focus mainly on weighting criteria and performing simulations to quantify alternatives' performance. Therefore, this paper presents a more complete Multi-criteria decision-making (MCDM) framework to support the decision-making process in renovation. To illustrate and validate the framework, it is implemented in two case studies based on a five-story building located in Spain. Each case includes five stakeholders. Two weighting settings are analysed to study the robustness and sensitivity of the proposed approach. The main contributions correspond to: 1) an MCDM enabling the participation of multiple stakeholders using the Pairwise comparison method; supporting the setting of objectives and criteria, promoting a comprehensive evaluation of the alternatives; and facilitating the integration of criteria weights and alternatives' performance through the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method; and 2) the validation of the proposed framework, especially the implementation of TOPSIS to evaluate renovation alternatives. Promoting the setting of objectives and criteria can enable discussions and encourage a broader and more complete analysis of renovation alternatives. In the two case studies, stakeholders included social aspects and assigned in total weights around 20% to this category. The Pairwise comparison and TOPSIS methods integrated the perspectives of stakeholders with different interests and the alternatives’ performance to obtain a shared view of the renovation and a final ranking of the alternatives to differentiate them accordingly and make a better-informed decision.

Renovation mode for growing underground pedestrian system within station area: a case study of Shanghai Jing’an Temple Station

The underground pedestrian system within Jing’an Temple Station area in Shanghai provides convenience for local pedestrians and promotes the compact development of surrounding urban area by building connections between the metro station and surrounding underground public spaces. On the other hand, deserted spaces and congested spaces still exist in this system. In this paper, based on the space syntax methodology, we first study the spatial configuration of this pedestrian system by conducting segment analysis. It is found that the system is roughly in a radial shape, with concentrated traffic pressure on the core and low accessibility on each end. Renovation alternatives are then developed towards those defects. By analyzing and comparing topological features, such as spatial configuration, accessibility and transit activity, among renovation alternatives, a renovating mode of the growing underground pedestrian system within station area is put forward that small walkable ringways are constructed successively and weaved into an underground walking network.

NZEB and market-based renovation case study of an existing office building

The goal of decarbonizing the building stock in the EU requires a multi-fold increase of the current renovation rates. In Estonia, the non-residential building sector has had little or no public support to improve the energy efficiency. Therefore, it is essential to study the energy efficient and cost-optimal measures for non-residential building renovation to give guidance to real estate companies and other stakeholders about the renovation alternatives. Furthermore, crucial is to provide input to the government to develop the renovation grant and incentives for renovation. In this study, energy renovation measures and savings to improve the energy performance to NZEB level were identified in a large (16 990 m2heated area) office building. For that purpose, energy use was measured, simulation model developed and calibrated, feasible and more comprehensive energy improvements and costs analysed. The improvement of lighting, AHU, heating, installation of a 69 kW PV system, and window replacement was needed to achieve the goal with a primary energy use of 163 kWh/m2. However, some of the applied measures had long payback times of 40-70 years and are not realistic to be implemented without renovation incentives.

Processes for Sustaining Energy in Noncertified Historic Buildings: A Case Study of Smith Plantation

This paper addresses energy efficiency, indoor air quality, and water consumption in historic buildings. Building sustainability has become a worldwide issue from new construction to existing buildings. Historic buildings make up a large part of existing buildings throughout the world, making it essential that research is done to provide these buildings with sustainable options. The areas of special concerns in renovating historic buildings are improving indoor environmental quality, indoor air quality, water efficiency, and energy efficiency while maintaining the historical value of these buildings. This paper presents a case study of the Smith Plantation in Metro Atlanta, Georgia. The study includes 1) field verification and existing condition assessment of the thermal comfort, energy consumption, and indoor air quality. 2) Building information modeling was used to simulate the energy performance of the buildings as well as determining the CO₂ footprint. These models were calibrated and verified against field readings. 3) the simulation models were used to generate design and renovation alternatives to improve the energy efficiency of these buildings as well as reducing the CO₂ footprint without impacting the originality of these buildings. This study will provide general design guidelines and renovation options for historic buildings to reduce energy consumption and creating a smaller carbon footprint while maintaining the authenticity of the buildings.

PARADIS - A process integrating tool for rapid generation and evaluation of holistic renovation scenarios

Recent research in building renovation seeks methods for the development of more holistic renovation scenarios that live up to a broader set of sustainability objectives and criteria, and that involve more stakeholders in the earlier stages of the design process. This paper presents a methodology for development of a Building Information Modeling (BIM) based decision support system PARADIS, which generates and evaluates optimal and holistic renovation scenarios tailored toward the renovation of dwellings in a Danish context. PARADIS supports the renovation sector with the following features: (a) optimizing the selection process of renovation alternatives, and the generation of renovation scenarios, through specific renovation typologies and constraints; (b) evaluating standard sustainability Key Performance Indicators (e.g. energy consumption, investment cost, indoor thermal comfort, etc.) over the generated renovation scenarios; and (c) visualizing the generated renovation scenarios for ease of comprehension by the designers, and for enabling discussion between expert stakeholders (i.e. engineers, contractors, facilities managers) and non-expert stakeholders (e.g. building occupants, owners, etc.). PARADIS thus supports informed decision making for optimal renovation scenario design. The first complete integrated toolchain, including a ready-to-release prototype of the PARADIS Revit plug-in, is demonstrated in this paper and empirically evaluated on a large apartment block in Denmark.

Decision-Making Process to Select Energy Efficient Renovation Alternatives for Residential Buildings: Two Case Studies

Decision-Making Process to Select Energy Efficient Renovation Alternatives for Residential Buildings: Two Case Studies

Development of a Weight Factor Method for Sustainability Decisions in Building Renovation. Case Study Using Renobuild

Energy efficiency investments have become strategically important for the European Union. In particular, energy efficient renovation and investment in the existing building stock have become major challenges. Renovation of a building should involve a holistic and integrated design process, which considers all aspects of sustainability. The aim of this work is to suggest a mathematical model that weighs economic, social and ecological aspects into a measure that supports housing owners/decision makers to find the optimal renovation alternative from their perspective, taking factors such as budget, energy consumption, etc. into consideration. Multi-criteria decision-making (MCDM) concerns structuring and solving multiple-criteria decision problems. MCDM has become popular in energy planning as it enables the decision maker to pay attention to all the criteria available and make the appropriate decision as per the priority of the criteria. In this study, the concept is introduced based on economic, social and ecological aspects assessed during a renovation project. A pedagogical example illustrates the suggested numerical system for comparing different renovation alternatives. The suggested method will facilitate decision-making processes in renovation projects and will allow decision makers to choose the best renovation alternatives that are in line with their business ideas and principles.

Energy efficiency in small districts: Dynamic simulation and technoeconomic analysis

In European Union Countries, local authorities have developed their own Sustainable Energy Action Plan aiming at planning the urban strategies to achieve the European Union and national 2020 energy targets. This document is used for detecting and deploying the energy measures which each municipality should adopt in order to reduce the environmental impact of the municipality activities. Further efforts are expected to define the strategies for achieving 2050 goals. In this framework, this work deals with the dynamic estimation energy saving actions for small districts located in different Italian weather zones (Naples and Turin, located in South and North Italy, respectively). The data of the Sustainable Energy Action Plan were used to develop suitable dynamic models, implemented in TRNSYS environment, including different buildings of selected districts. In particular, all the buildings were modelled by means of the Type 56 of TRNSYS, coupled to the Google SketchUp TRNSYS3d plug-in. By means of Type 56, it is possible to take into account and simulate the buildings geometry, envelope, windows, lighting, machineries heat gains schedule as well as the buildings users’ occupation and activity. Given the loads, several energy efficient renovation alternatives based on the adoption of air-to-air conventional and carbon dioxide heat pumps, evacuated thermal collectors and photovoltaic panels, as well as the envelope renovation of all the public and private buildings of the district, are proposed and compared. Results, obtained by detailed dynamic energy and environmental analyses, can be used as guidelines for the local authorities to implement suitable energy efficiency actions of existing buildings in order to reduce both the thermal energy and carbon dioxide emissions due to the building space heating/cooling, domestic hot water and electricity. The proposed renewable layout for Naples case study achieves a primary energy savings of 58% with a payback period of 4 years. The renewable layout for Turin case study achieves a primary energy savings of 76% with a payback period of 10.6 years.

Energy-Efficient Office Renovation

Energy-Efficient Office Renovation

Energy-Efficient Office Renovation

Energy-Efficient Office Renovation

A new procedure for assessing the energy-efficient refurbishment of buildings on district scale

Energy-efficient renovation of buildings is in a major role in achieving the climate targets. Refurbishment at district scale may contain several benefits compared to mere building renovations, such as reduced costs due to smaller unit costs. Furthermore, it provides municipalities better opportunities to implement energy and sustainability strategies.This paper introduces a district-scale procedure for analyzing energy-efficient refurbishment of buildings. The main targets for the developed procedure were: 1) easy way for feeding information, 2) dynamic calculation capacity, and 3) support for decision makers. In order to support the targets, the procedure combines energy simulation, 3D data modelling and visualization. Additionally, CityGML is utilized to receive building related district data.The procedure was tested in a Finnish case district where altogether six realistic refurbishment scenarios were compared by means of operational costs, energy usages and CO2 emissions. The test analyses demonstrates that different scenarios may have conflicting impacts which give important information to the decision-makers. The procedure is not limited to the demonstrated scenarios but it can be modified for different purposes. Additionally, the procedure was compared to other district-level procedures identified from the literature. The procedure turned out to be a promising basis for assessing district-scale energy renovation alternatives.

The importance of life-cycle based planning in maintenance and energy renovation of multifamily buildings

Improving the energy performance in the real estate sector has become increasingly important and drawn a lot of attention during the past few decades. Despite all the technological developments, the energy efficiency measures are yet expensive and when implemented only to improve the energy performance, are rarely economically justified. To lower the costs of energy performance improvements, an alternative is to combine energy efficiency measures with already required renovation measures. The problem with renovation on the other hand, is that its planning is not strategic; it is mainly opportunistic, short-term and with the focus on the capitalization of newly-discovered opportunities, meaning that renovation measures are coupled when one or more of the rather costly building components have reached failure. The take on an opportunistic approach, however convenient, results in loss of value which is most often neglected in the economic evaluation of renovation projects. The lack of strategic planning and the subsequent loss of value become more important in less-attractive markets, where there are both budget constraints and socio-economic issues. Energy performance and/or living standard are often sacrificed through improper distribution of resources as the choice of renovation measures are often influenced by the return of investment. Therefore, a proper evaluation of renovation alternatives not only can satisfy the technical and financial requirements but also help maintain proper living standard and improve the energy performance in multifamily buildings. In a prior study, authors have proposed a systematic approach to cost-optimal maintenance and renovation planning by combining the deterioration function of building components with respective service-life cycle costing. This paper presents an extension of that methodology to include the energy efficiency option pricing as an optimization criterion. The extended methodology is meant to provide support for housing owners in building management in forms of technical and economic evaluation of possible energy-renovation scenarios under time/budget constraints. To demonstrate the application of the methodology, maintenance/renovation plans are devised for three building components with sharing fixed costs (windows, faöade and roof) in both new and existing multifamily buildings.

Using Virtual Reality for assessing the role of noise in the audio-visual design of an urban public space

Sound planning is not often included in the urban design process despite the well-known audio-visual interactions of human perception. A methodology to compare the overall appreciation of future renovation alternatives of urban public spaces using Virtual Reality Technology is proposed. This method is applied to assess the role of noise in the overall appreciation of a walk on a bridge crossing a highway. The auralization is a dynamic 3D surround based on B-format recordings (ambisonics), filtered by means of full-wave numerical calculations obtaining the sound field behind noise barriers along the bridge’s edge. Four different styles of visual street design including different noise barrier heights in combination with the 4 corresponding predicted sound fields were evaluated for their pleasantness by 71 normal-hearing participants on 4 separate days. Each day participants experienced all the visual environments with only one soundscape (to elude direct sound comparison) and anything related to sound was not mentioned in the first part of the experiment. Even in this non-focussed context, a statistically significant effect of the sound environment on the overall appreciation was found. In general, the pleasantness increases with traffic noise level reduction, but the visual design has a stronger impact. By mentioning the soundscape while introducing the evaluation, slightly lower (but statistically significantly different) pleasantness ratings were obtained. Instead of increasing noise barrier height, improving the visual design of a lower barrier seems more effective to increase pleasantness. Visual designs including vegetation strongly outperform others. The virtual experience was rated as immersive and realistic.

Evaluation of the criticality of thermal bridges

Thermal bridges can be an important reason for the renovation of old apartment buildings. This study presents a method for the critical analysis of thermal bridges. The risk of failure, i.e., surface condensation or mould growth, is evaluated by using the temperature factor f Rsi.load based on indoor hygrothermal loads and the temperature factor f Rsi.resistance from thermography measurements. The proposed method is employed for two practical applications—a case study analysis of the entire Estonian apartment building stock and a case study concerning the thermal bridges before and after the renovation of a precast concrete large-panel apartment building. The results show that critical thermal bridges caused by low surface temperature exist in all types of apartment buildings. The measured temperature factors were as low as f Rsi.res < 0.65 for several junctions in concrete buildings and for the external wall/window junctions of brick buildings. The temperature factors from indoor hygrothermal loads are as high as f Rsi.load = 0.99 for the worst dwelling unit and f Rsi.load = 0.80 at a 90% reliability level for mould growth in concrete buildings. The calculated risk for surface condensation is 45–51% and for mould growth is 45–54%; this is highest in concrete buildings for both criteria. The calculated results are confirmed by visually detected mould growth, which ranges between 28 and 46% depending on the type of building. The proposed method can be used in stochastic analysis if the present need for renovation or designed renovation alternatives is under consideration.

Pending for Renovations: Understanding the Conditions of the Multi-family Housing Stock from before 1945

The Swedish housing stock is once again in focus for national energy savings, as it was after the oil crises in the 1970s and 1980s. The contemporary debate has a one-sided focus on energy savings and barriers for implementation of existing energy efficient renovation measures but also on large stock of industrialized housing built after 1960. The need for renovation is equally urgent in older stocks of housing, also in those that already have been renovated but are in need for further interventions. In this paper we focus on multi-residential housing built before 1945 in Gothenburg, Sweden, representing cultural and historical heritage values. The opportunities to ensure high energy efficiency with new measures in a second renovation should aim to find a balance with heritage values, social values, function, aesthetics and management aspects. In order to get an understanding of the conditions of the stock in focus, we apply both a top-down and bottom-up approach. In the top-down approach, data are gathered from different sources such as energy performance certificates, the national property register, and geodata from the City of Gothenburg. By combining information from these databases, three data subsets have been defined for the bottom-up approach: non-renovated buildings, buildings renovated to a small extent and buildings renovated to a large extent. Three case study buildings were selected out of these data subsets. The choice of renovation strategy differs between the cases. Case study building 1 has been left virtually untouched while case study building 2 and 3 have been renovated to different extent. The next step in this research project is to identify suitable renovation alternatives for these building typologies.

Towards a New Integrated Spatial Decision Support System in Urban Context

The current growth of urbanization rate indicates that this trend is not going to stop, and therefore, it stresses the necessity of actions for mitigating the local and global pollution. Moreover, most of the actual stock is characterized by low energy performances since it pre-dates the energy regulation. The paper aims at addressing this issue by proposing the integration of Building Simulation (BS) approach, Multi-Criteria Analysis (MCA)methods and Geographic Information System (GIS)tool for developing a newMulti-Criteria Spatial Decision Support System (MC-SDSS)in urban context. The BS of relevant building archetypesallows to identify different resolutions of energy data: hour-by-hour data can be useful for demand-side management or renewable integration while aggregated data can be used for load forecasting and retrofit simulations. TheMCApermitschoosing between different building renovation alternatives by considering both qualitative and quantitative criteria. Moreover, the GIS support the method by creating geo-referenced databases. The methodpurposes in giving a comprehensive view to address the complexity of urban building energy planning; due to its flexibility, it can be applied to several urban areas. Three main phases characterize the study: i. overview of relevant existing techniques; ii. description of the integrated proposed method; iii. discussion and future application. The method can provide relevant feedbacks for ranking complex design energy options.