1.
Ylmen, Peter, et al.
(författare)
The influence of secondary effects on global warming and cost optimization of insulation in the building envelope
2017
Ingår i: Building and Environment. - : Elsevier BV. - 0360-1323 .- 1873-684X. ; 118, s. 174-183
Tidskriftsartikel (refereegranskat) abstract
The relative environmental impact from the building construction phase is increasing compared to the operation phase for new buildings. Therefore, it is important to consider the complete environmental life cycle of energy improvement measures. Many advanced optimization methods have been developed in recent years to assess building life cycle impact. However, these previous studies have not fully addressed the secondary effects, in other words, indirect effects outside the actual design option. This may lead to conclusions of optimization studies based on misleading calculation results. The main purpose this study was to highlight the relevance of including secondary effects in optimization of building design with respect to global warming potential and cost. This was done by conducting a parameter study of the building envelope insulation thickness with regard to global warming potential and life cycle costs, while considering secondary effects induced by the different design options. Findings from this study show that secondary effects influence the system boundary, algorithm architecture, results and the final conclusions of optimal building design. Omitting secondary effects can thus lead to incorrect decision on optimal solutions with regard to global warming potential and life cycle cost. Therefore, it is therefore important to take them into consideration when performing optimization studies of building design options.
2.
Wu, Pei-Yu, et al.
(författare)
A Data-Driven Approach to Assess the Risk of Encountering Hazardous Materials in the Building Stock Based on Environmental Inventories
2021
Ingår i: Sustainability. - : MDPI AG. - 2071-1050. ; 13:14
Tidskriftsartikel (refereegranskat) abstract
The presence of hazardous materials hinders the circular economy in construction and demolition waste management. However, traditional environmental investigations are costly and time-consuming, and thus lead to limited adoption. To deal with these challenges, the study investigated the possibility of employing registered records as input data to achieve in situ hazardous building materials management at a large scale. Through characterizing the eligible building groups in question, the risk of unexpected cost and delay due to acute abatement could be mitigated. Merging the national building registers and the environmental inventory from renovated and demolished buildings in the City of Gothenburg, a training dataset was created for data validation and statistical operations. Four types of inventories were evaluated to identify the building groups with adequate data size and data quality. The observations' representativeness was described by plotting the distribution of building features between the Gothenburg dataset and the training dataset. Evaluating the missing data and the positive detection rates affirmed that reports and protocols could locate hazardous materials in the building stock. The asbestos and polychlorinated biphenyl (PCB)-containing materials with high positive detection rates were highlighted and discussed. Moreover, the potential inventory types and building groups for future machine learning prediction were delineated through the cross-validation matrix. The novel study contributes to the method development for assessing the risk of residual hazardous materials in buildings.
3.
4.
Wu, Pei-Yu, et al.
(författare)
Tracing hazardous materials in registered records : A case study of demolished and renovated buildings in Gothenburg
2021
Ingår i: Journal of Physics. - : IOP Publishing.
Konferensbidrag (refereegranskat) abstract
Hazardous materials encountered during building renovation or demolition processes not only result in uncertainty in cost estimation and the lead time but also hampers material recyclability and reuse. Therefore, the paper discusses the possibility of predicting the extent of the hazardous materials, including asbestos, PCB, mercury, and CFC, through data mining techniques based on registered records. Pre-demolition audits contain observation data that can be used as a sample for statistical prediction through careful processing. By developing an innovative approach of merging data from environmental inventories with building registers, the positive ratio of remaining hazardous materials in the Gothenburg building stock can be estimated. The study highlights the challenges of creating a training dataset by completing information from the existing environmental inventory, providing new insight into digital protocol development for enhancing material circularity.
5.
Abdul Hamid, Akram, et al.
(författare)
Impact of high residential density on the building technology, HVAC systems, and indoor environment in Swedish apartments
2020
Ingår i: E3S Web of Conferences. Volyme 172, 2020.. - : EDP Sciences. ; 172
Konferensbidrag (refereegranskat) abstract
During the last few years, there has been an increased number of overcrowded apartments, due to increased migration but also housing shortage in general, particularly in the suburbs to major cities. The question is how the indoor environment in these apartments is affected by the high number of persons and how the problems related to high residential density can be overcome. This paper aims to specify the problem by investigating and analysing the technical parameters influenced by residential density in Swedish apartments built between 1965-1974. To map the situation, 11 interviews with employees at housing companies were conducted. Based on extreme conditions described in the interviews, simulations of the indoor climate and moisture risks at some vulnerable parts of constructions were made. Simulations were focused on moisture loads and CO2 concentrations as functions of residential density and ventilation rate. Finally, measures to combat problems associated to overcrowding are suggested. The aim is that the results should be used by authorities to formulate incentives and/or recommendations for housing companies to take actions to ensure a good indoor environment for all, irrespective of residential density conditions. © The Authors.
6.
Mangold, Mikael, et al.
(författare)
Fastighetsägares förutsättningar för renovering av sina byggnadsbestånd från miljonprogramstiden
2018
Ingår i: Bygg och Teknik. - 0281-658X .- 2002-8350. ; 2
Tidskriftsartikel (populärvet., debatt m.m.) abstract
Byggsektorn står inför ett stort renoveringsbehov. Byggnader från miljonprogramstiden har nått en ålder då många olika byggnadsdelar når sin förväntade livslängd. Detta renoveringsbehov är inte jämnt fördelat bland Sveriges fastighetsägare. Det stora flertalet av de ännu ej renoverade byggnaderna från miljonprogramstiden ägs av fastighetsbolag knutna till SABO, men det finns även många privata fastighetsägare och bostadsrättsföreningar som har ett eftersläpande renoveringsbehov eller som har renoverat men fortfarande har en hög energianvändning och alltså troligtvis inte genomfört nödvändiga energieffektiviseringsåtgärder. Det finns också olika förutsättningar för att göra de investeringar som krävs, vilket beror på företagens soliditet, fastigheternas värde och möjligheten att få lån, utrymme för hyresökning etc. Detta gör att renoveringstakten inte kommer att täcka renoveringsbehovet och att vissa delar av fastighetsbeståndet kommer att vara mer eftersatt.
7.
von Platten, Jenny, et al.
(författare)
A matter of metrics? : How analysing per capita energy use changes the face of energy efficient housing in Sweden and reveals injustices in the energy transition
2020
Ingår i: Energy Research & Social Science. - : Elsevier Ltd. - 2214-6296 .- 2214-6326. ; 70
Tidskriftsartikel (refereegranskat) abstract
Improving energy performance of the housing stock continues to be an important undertaking in the energy transition of many EU member states. However, tendencies of low-income households generally living in buildings with low energy performance pose a challenge for this transition, and cases of ‘renoviction’ and ‘green gentrification’ are becoming more and more noticed in the scientific community. More so, questions regarding the distributive justice of costs and burdens in the energy transition of the housing stock have been raised. In this paper, we approach this problem from a perspective of energy performance metrics. Although energy performance (kWh/m2, year) is generally lower in buildings inhabited by low-income households, residential density—and thus building utilisation—tends to be higher. By measuring per capita energy use instead of area-normalised energy use, we investigate if a high residential density can offset a low energy performance and change the perception of which buildings are considered energy inefficient and which are not. Results showed that by measuring per capita energy use instead of area-normalised energy use, energy inefficient buildings were found in high-income city centres instead of in low-income suburbs of Swedish cities. Moreover, there has been an unjust distribution of the imposition of the energy transition over the past decade where the residents with the initially lowest per capita energy use have carried a disproportionately high share of the energy savings. This suggests that a change of energy performance metrics could offer an approach for a more socially just and sustainable energy transition of the housing stock. © 2020 The Author(s)
8.
Ylmen, Peter, et al.
(författare)
Life Cycle Assessment of an Office Building Based on Site-Specific Data
2019
Ingår i: Energies. - : MDPI AG. - 1996-1073. ; 12:13
Tidskriftsartikel (refereegranskat) abstract
Life cycle assessment (LCA) is an established method to assess the various environmental impacts associated with all the stages of a building. The goal of this project was to calculate the environmental releases for a whole office building and investigate the contribution in terms of environmental impact for different parts of the building, as well as the impact from different stages of the life cycle. The construction process was followed up during production and the contractors provided real-time data on the input required in terms of building products, transport, machinery, energy use, etc. The results are presented for five environmental impact categories and, as expected, materials that constitute the main mass of the building and the energy used during operation contribute the largest share of environmental impact. It is usually difficult to evaluate the environmental impact of the materials in technical installations due to the lack of data. However, in this study, the data were provided by the contractors directly involved in the construction and can, therefore, be considered highly reliable. The results show that materials for installations have a significant environmental impact for four of the environmental impact categories studied, which is a noteworthy finding.
9.
Ylmén, Peter, et al.
(författare)
Managing choice uncertainties in life-cycle assessment as a decision-support tool for building design : A case study on building framework
2020
Ingår i: Sustainability (Switzerland). - : MDPI AG. - 2071-1050 .- 1548-7733. ; 12:12
Tidskriftsartikel (refereegranskat) abstract
To establish a circular economy in society, it is crucial to incorporate life-cycle studies, such as life-cycle assessment (LCA), in the design process of products in order to mitigate the well-recognized problem of the design paradox. The aim of the study was to provide means in a structured way to highlight choice uncertainty present in LCA when used as decision support, as well as to mitigate subjective interpretations of the numerical results leading to arbitrary decisions. The study focused on choices available when defining the goal and scope of a life-cycle assessment. The suggested approach is intended to be used in the early design phases of complex products with high levels of uncertainty in the product life-cycle. To demonstrate and evaluate the approach, a life-cycle assessment was conducted of two design options for a specific building. In the case study two types of building frameworks were compared from an environmental perspective by calculating the global warming potential, eutrophication potential, acidification potential, stratospheric ozone depletion potential and photochemical oxidants creation potential. In the study, a procedure named the Decision Choices Procedure (DCP) was developed to improve LCA as an effective tool for decision support concerning design alternatives when less information is available. The advantages and drawbacks of the proposed approach are discussed to spur further improvements in the use of LCA as a decision-support tool.
10.
Ylmen, Peter, et al.
(författare)
The importance of including secondary effects when defining the system boundary with life cycle perspective : Case study for design of an external wall
2017
Ingår i: Journal of Cleaner Production. - : Elsevier BV. - 0959-6526 .- 1879-1786. ; 143, s. 1105-1113
Tidskriftsartikel (refereegranskat) abstract
Life cycle assessment and life cycle cost analysis are suitable tools in trying to minimize environmental impact and cost. To get reliable results it is crucial to set up correct system boundaries for the investigation, but it is often difficult to understand a complex products system because of the cascade effects of consequences that can be induced even by small changes. In this paper the effects and consequences evaluation (ECE) method is introduced to systematically identify and organize the effects and consequences for a design change of parts of a complex system. The method is applied in a case study of external wall insulation for a new building to investigate the importance of correct system boundaries. Using the methodical approach in identifying all significant consequences showed that unexpected unit processes can be important when deciding on the relevant system boundary. We also conclude that such processes can have a significant impact on the final results by calculating the change in global warming potential and life cycle cost for the processes affected by the design option.
