Functional testing of waterproofing systems for use behind ceramic tiling based on flexible sheets 2019

Functional testing

The result is worse than before.

Six (32%) of the nineteen tested waterproofing systems passed the function test without leakage. Thirteen (68%) tests resulted in leakage.

This result is worse than that obtained in the previous project in 2016, (1) when eight (40%) of twenty tested waterproofing systems passed the functional test without leakage. There has therefore been some deterioration in the as constructed systems.

The result, however, is better than in the project performed in 2014 (2) when only three (15%) of twenty tested waterproofing systems passed without leakage.

In this project, several leakages are localised around the penetrations of large and small drainpipes. This is an increase compared to previous studies. We have seen on several occasions that pipe collars have had poor quality. This has been noticed by that the polymer material used for sealing around the tube has lost its water tightness ability during the test. It is most probable that the material has a residual deformation (from setting) that causes the material to lose its ability to seal around the tube. We have also noted that the pipe collars have delaminated i.e. the layers in the collars have been divided into their individual constituents during the test.

Leakages have also been caused by connections to gullies, inside corners, outside corners and in joints of foils.

Fortunately, none of the investigative systems showed leakage that was so extensive that one could describe it as total damage.

Water vapour resistance and mass per unit area

Thirteen tested waterproofing on flexible sheet systems show a result between 2,5 and 4,5 million s/m, which is a high or very-high water vapour resistance. Six flexible sheet systems have a result below 2,5 million s/m.

In the determination of water vapour resistance and mass per unit area, we can clearly see that some manufacturers have made changes in or replaced their flexible sheet with a new one, compared with the previous investigation (1).

We further note that 10 out of 14 flexible sheets have a lower water vapor resistance than in the previous investigation (1). It is also notable that the PVC sealing layer has a low water vapor resistance.

Indication of long-term properties

In order to obtain an indication of the amount added antioxidants that improves the long-term properties of the materials, the DSC analysis of flexible sheets have been performed. In the same way as in the previous project, 2016, (1) it seems that the flexible sheets to be more stabilized for long-term use compared to the previous study in 2014, (2). However, for all analysed materials, to make a reliable service life prediction of the material, an accelerated ageing at moderate temperature is recommended.

Plasterboard is a common building material used in several parts of a building. In the case of retrofitting and demolition a part of the waste consists of components combined with the plasterboards, for example, frame work timber.

In the case of new construction and retrofitting, construction waste is produced from clean plasterboard boards, either as cut off pieces or as unused whole boards. This waste can be used as raw material to produce new plasterboards. Manufacturers want to use gypsum from wasted boards to decrease the use of primary gypsum from mining and the quality requirements are relatively easy to achieve.

In this project it has been found that the major construction companies already handle gypsum from new construction separately. This waste fraction could already be used in the production of new boards. Gypsum from retrofitting is usually assembled with other building materials and require more extensive efforts to achieve necessary purity to be used in the productions of new boards. Today, plasterboard waste is deposited or used to improve soil and/or sludge. In order to increase the recycling of plasterboards new inventory routines of rebuilding and demolition projects need to be elaborated. New tools and methods for dismantling plasterboard need to be development to achieve safe working environment and environmentally and economically sustainable recycling.

Preparation plants producing raw material from plasterboard waste are already in operation. Today the waste mainly is wastage from the production stage. In order to increase the recycling of plasterboards from the construction- and demolition branch new logistic systems need to be developed, for example by creating collection points for gypsum board waste and / or developing new transport vehicles and systems. Prerequisites of changing the system of piece work in the construction industry need to be investigated with the intension to create a more sustainable building industry.

During the last decade, the use of timber (especially massive timber) has increased worldwide, mainly driven by anticipated environmental benefits. However, there is debate on how to handle the susceptibility against microbial growth for wooden constructions, especially during the construction phase. Sometimes full weather protection is used to avoid exposing the wooden material to outdoor conditions, but oftentimes the structures are fully exposed to precipitation. In an earlier study, one construction site using a full weather protection was studied, and the results showed promising results on the improved hygrothermal conditions and reduced risk of mould growth. Moreover, the site contractor also indicated improved work environment and productivity, however, this was not included in that study. This present study aims to investigate the effects of using full weather protection during construction in seven different construction projects to follow-up and broaden the earlier single project study. The studied aspects include the hygrothermal conditions, potential of mould growth, and influence on the work environment. Temperature and relative humidity were measured and analysed. Samples of cross-laminated timber (CLT) were analysed using a microscope, and the results are compared to theoretical mould growth potential. This is measured both inside the weather protection and outside at the seven construction projects. Furthermore, a work environment questionnaire is distributed to workers at the sites to collect the perceived work environment using a full weather protection. The results of the study partly confirm the conclusions from the earlier study, i.e., reducing the risk of mould growth and causing a slightly warmer and dryer conditions than outside. In addition, the results indicate an improved work environment. The majority of the interviewees wishes a weather protection in their next project regarding the work environment.

Since the buildings and construction sector is one of the main areas responsible for energy consumption and emissions, focusing on their refurbishment and promoting actions in this direction will be helpful to achieve an EU Agenda objective of making Europe climate-neutral by 2050. One step towards the renovation action is the exploitation of digital tools into a BIM framework. The scope of the research contained in this paper is to improve the management of information throughout the different stages of the renovation process, allowing an interoperable exchange of data among the involved stakeholders; the development of an innovative BIM-based toolkit is the answer to the research question. The research and results obtained related with the development of an interoperable BIM-based toolkit for efficient renovation in buildings in the framework of the European research project BIM4EEB. Specifically, the developed BIM management system allows the exchange of the data among the different tools, using open interoperable formats (as IFC) and linked data, in a Common Data Environment, to be used by the different stakeholders. Additionally, the developed tools allow the stakeholders to manage different stages of the renovation process, facilitating efficiencies in terms of time reduction and improving the resulting quality. The validity of each tool with respect to existing practices is demonstrated here, and the strengths and weaknesses of the proposed tools are described in the workflow detailing issues such as interoperability, collaboration, integration of different solutions, and time consuming existing survey processes. © 2021 by the authors.

The reference level for effective dose due to gamma radiation from building materials and construction products used for dwellings is set to 1 mSv per year (EC, 1996, 1999), (CE, 2014). Given the specific conditions presented by the EC in report 112 (1999) considering building and construction materials, an I-index of 1 may generate an effective dose of 1 mSv per year. This paper presents a comparison of the activity concentrations of 4 0K, 226Ra and 232Th of aggregates and when these aggregates constitute a part of concrete. The activity concentration assessment tool for building and construction materials, the I-index, introduced by the EC in 1996, is used in the comparison. A comparison of the I-indices values are also made with a recently presented dose model by Hoffman (2014), where density variations of the construction material and thickness of the construction walls within the building are considered. There was a ~16-19% lower activity index in concretes than in the corresponding aggregates. The model by Hoffman further implies that the differences between the I-indices of aggregates and the concretes' final effective doses are even larger. The difference is due, mainly to a dilution effect of the added cement with low levels of natural radioisotopes, but also to a different and slightly higher subtracted background value (terrestrial value) used in the modeled calculation of the revised I-index by Hoffman (2014). Only very minimal contributions to the annual dose could be related to the water and additives used, due to their very low content of radionuclides reported.

Eco-neighborhoods with gardens on concrete decks are for several reasons increasingly being prescribed today in major Swedish cities. However, there is a lack of knowledge, experience, standards and guidelines as well as collaboration between parties and stakeholders when installing such systems. It is incredibly important to avoid any leakage during the lifetime of a green roof garden but this cannot be completely guaranteed with today’s installation practice and project management. At Sustainable City 2014 in Siena, we presented a paper about a new project aiming at bringing together researchers, government and industry to collaborative development of new and attractive solutions for green roof gardens with consideration to the environment and high requirements for durability, materials, construction and energy efficiency. This paper is a continuation of the paper presented in Siena and reports on the most recent results from the collaborative project which will finalize in November 2016. After that, the project will be further evaluated in a proposed continuation project for another couple of years.

Reducing the emissions of greenhouse gases is of utter importance for the mitigation of climate change mitigation. In Sweden, the building and service sector is responsible for 21% of total greenhouse gas. Renovating existing buildings, more specifically those which were constructed before 1980, can significantly contribute to the reduction in energy consumption and emissions of greenhouse gases. Because the majority of these buildings are in need for renovation. But the energy renovation and energy efficiency-related maintenance rate in Sweden is very low due to lack of technical drawings and documentation of information about material specifications and structure systems. Adoption of augmented reality technologies can be beneficial as these technologies present digital information in the context of the physical environment. However, the level of adoption of these technologies in renovation and maintenance projects is still very low. This paper expands the technology acceptance model to evaluate determinants of users’ acceptance of augmented reality technologies in renovation and maintenance projects.

Multidisciplinary approach is used to evaluate concrete with recycled concrete aggregates (RCA) from technical, environmental impacts and product circularity perspectives. Two RCA replacements investigated, RAC50: fine aggregates; RAC100: both coarse, fine aggregates. Reference, recycled concretes have same cement content, similar workability and compressive strength requirement, proven experimentally. RCA is sourced from pre-fab element discards of a Swedish plant, the logistical alternatives requiring environmental impact analysis. Alternatives are RCA crushing at plant and crushing at a different location including transportation. LCA shows transportation is second largest contributor after cement in all impact categories. RAC alternatives show lower total impact than reference concrete due to RCA replacement. A circularity index for concrete based on economic value of recirculated aggregates; supplements LCA for sustainability reporting. Circularity index results: RAC100 > RAC50 > RC. Combining circularity index with LCA helps optimize recycling process with regard to amount of recycled material and logistics respectively. © 2022 The Author(s).

The environmental impacts of the construction industry, and the built environment, as the end product of construction activity, are massive due to the extensive use of energy and resources. Sustainability and circular economy are recognized as the main solution to the existing environmental impacts of this industry and the main approach to the sustainable development of it. The transition of a construction project’s life cycle from a linear one starting with material processing and ending up at demolition stage to a real cyclic life cycle needs defining alternative end-of-life scenarios. Deconstruction as one of the alternative end-of-life scenarios is defined as salvaging material of a dismantled structure for reuse or recycling. Design for deconstruction refers to the importance of considering deconstruction as the end-of-life scenario in the design stage of structures. This thesis aims to define the existing challenges and opportunities in the deconstruction of timber structures by the study of cases in which dis- and re-assembly are done. The study also aims to measure deconstructability by developing an indicator system for design for deconstruction of volumetric timber structures based on design for disassembly principles existing in ISO 20887:2020 and the practical principles of the case studies. This is done by interviewing people at five different companies who were engaged in the dis- and re-assembly of structures. The study of these cases shows the gap between disassembly principles and real-world experience from a learn-from-practice point of view. The developed tool as the indicator system is consisted of 25 indicators under seven principles and is able to measure and provide a deconstructability grade of structures out of 100 for each principle and a total deconstructability grade based on all principles.

The report presents a two-piece literature summary summarizing incentives and regulatory barriers to the renovation of multi-family houses, as well as general regulations, policies and other conditions for installations of solar cell installations. For developers and suppliers with interest in roof renovation with solar cells, the report aims to provide a picture of the conditions for such actions. The overall picture is that there is a rapid positive development of incentives and regulations specifically for solar cells. Additionally, regulations for energy efficiency and environmental certification can motivate property owners to carry out such combined approach.

This report complements the project report for project "Environmental Roofing - Solar Energy Redevelopment" (Energy Agency Project Number: 41857-1) and is available via E2B2's website - http://www.e2b2.se/.

In the collaborative forum Positive footprint housing® Riksbyggen is building the Viva residential quarter, which is a sustainability project at the very forefront of what is possible with contemporary construction. The idea is that this residential quarter should be fully sustainable in ecological, economic and social terms. Since 2013, a number of pilot studies have been completed under the auspices of the Viva project framework thanks to financing from the Swedish Energy Agency. The various building frame alternatives that have been evaluated are precast concrete, cast in-situ concrete and solid wood, all proposed by leading commercial suppliers. The report includes a specific requirement for equivalent functions during the use phase of the building, B. An interpretation has been provided that investigates the building engineering aspects in detail, as well as an account of the results based on the social community requirements specified in Viva, durability, fire, noise and energy consumption in the Swedish National Board of Building, Planning and Housing building regulations (BBR), plus Riksbyggen’s own requirements, Sweden Green Building Council’s Environmental Building Gold (Miljöbyggnad Guld) and 100-year life cycle. Given that the alternatives have different long-term characteristics (and also that our knowledge of these characteristics itself varies), these functional requirements have been addressed by setting up different scenarios in accordance with the EPD standard EN 15978. Because Riksbyggen has specified a requirement for a 100-year life cycle, we have also opted for an analysis period of 100 years. The results show no significant differences between concrete and timber structures for the same functions during the life cycle, either for climate or for primary energy. The minor differences reported are accordingly less than the degree of uncertainty involved in the study. The available documentation on the composition of the relevant intumescent paint coating on solid wood frames differs from source to source, so it was not possible to fully allow for the significance of this. The LCA has not included functional changes in the building linked to load-bearing characteristics, noise, moisture, health or other problems that may result in increased maintenance and replacement. The concrete houses have been dimensioned for 100 years, for instance, in accordance with tried and tested standards and experience. The solid wood house is not dimensioned in the same way, and this has led to us having to assume various scenarios.

The results also show the following:

• The uncertainties involved in comparing different structures and alternative solutions are very significant. The results are affected by factors such as life cycle, the functional requirements taken into consideration, transportation, design and structural details, etc.

• Variations in the built items and a considerable degree of uncertainty in the assumptions make it difficult to obtain significant results on comparisons. Only actual construction projects with known specific data, declared from a life cycle perspective that takes into account actual building developer requirements and involving different scenarios (best, documented and worst-case) for the user stage can currently be compared.

• In the other hand, comparisons restricted to different concrete structures only, or to different timber structures only, ought to involve a lower degree of uncertainty. These would then provide results that are significant as well as improvement requirements that are relevant.

• There is potential for improving concrete by imposing requirements on the material

• There is potential for improving solid wood frames by developing and guaranteeing well-documented long-term characteristics for all functional requirements.

The LCAs were performed as an iterative process where all parties were given the opportunity to submit their viewpoints and suggestions for changes during the course of the work. This helped ensure that all alternatives have been properly thought through.

Because, during the project, Riksbyggen opted to procure a concrete frame, in the final stage the researchers involved focused on ensuring the procurement process would result in the concrete frame as built meeting the requirements set out above. As things currently stand, the material requirements for the concrete are limited by the production options open to the suppliers, and this is therefore being investigated in the manufacture of precast concrete frames for the Viva cooperative housing association.

Concrete is the most common and widely used construction material in the world, with a consumption of approximately 1.5 tons per capita annually worldwide. This consumes 3000 million ton of cement, around 400 kg per capita. Sweden consumes around 250 kg of cement per capita.  The production of Portland cement consumes around 3500 MJ energy per ton. In addition, Portland cement production releases considerable amounts of CO2 when limestone is heated and calcinated. With 800 kg of CO2 per ton of cement around 5 % of the global release of CO2 comes from cement clinker production. About half of this comes from the limestone. Concrete, however, also binds CO2 when it is carbonated. In a geological time perspective, all concrete will carbonate and thus half of the released CO2 will be bound to carbonated concrete, which would reduce the environmental impact (Xi et al 2016). I reality the absorption is much less, and is related to the time interval of interest.  How fast CO2 will be absorbed depends on the type of concrete or cementitious material, site of the concrete, amount of CO2 in the environment and the environment as such, etc. It is also depending on the amount CO2 in the atmosphere and the temperature. In the end, to be able to calculate the uptake it is important to find out what happens with the concrete after demolition and if it is possible to increase the speed of carbonation.  This report mainly cover the mechanism and mode of carbonation to be able to get a better and more accurate understanding of how to calculate carbonation and CO2 uptake.  This project was funded by the Swedish Consortium for financing Basic research in the Concrete Field. The consortium members are: Cementa, Färdig Betong, Abetong, Swerock, Betongindustri and Strängbetong.

Many studies have shown that wooden buildings in general have a lower climate impact than buildings built of conventional materials such as concrete and steel. In Sweden, however, only about 10% of the multi-dwelling buildings are built with timber frames. The goal of this empirical study is to provide a broad picture of the views of Swedish actors regarding the use of wood products in multi-storey residential buildings and suggest measures for an increased use. A questionnaire concerning the use of wood products in construction was sent out to Swedish developers, main contractors, and architects and 100 answers were received. The study shows that the views of the groups of actors differ in some respects and factors that may either facilitate or be obstacles to an increased use of wood products were identified and discussed.

Contractors are expected to present their sustainability work in connection with procurement. But what is required is not always clear. The client could for example ask what the contractors are doing to contribute to environmentally or socially sustainable development. This pre-study surveys how the clients set requirements for sustainability work in procurement today and how the contractors respond to these requirements in their tenders, but also how the contracting companies work with sustainability in practice. The contractors hope that the concepts and requirements used in sustainability work will be clearer, more rigorous and easier to live up to so that they can truly contribute to a sustainable society. They would like to see it as a long-term work where they build up skills and routines in many projects instead of just a few pilot projects. Based on the results, the need of new tools or better use of existing tools to strengthen the work on sustainable construction projects were identified. The pre-study is carried out mainly through interviews with representatives from 15 companies as well as analysis and discussion of the answers during one workshop.

A public housing company has applied a new renovation strategy, comprising no standards raising and thus rent-raising measures, in 20% of its apartments. Prior to renovation, the tenants were given the opportunity to choose renovation options involving different standards and costs after renovation. The purpose of the study is to follow up and give feedback on the renovation strategy. The aim was to evaluate implementation of the strategy in practice using a case study, in terms of the tenants’ opportunity to influence and the housing company’s profitability. To follow up, two methods were used: a survey of the tenants’ perception of choosing renovation options, and a financial assessment of the profitability based on the renovation cost and rent increase for different choice scenarios. The results from the survey show that the tenants appreciate being able to choose between different renovation options as it gives them the opportunity to decide on their housing costs and standard. With more than half of the tenants choosing the maintenance option involving a very low rent increase, the dividend yield will not be high enough to make the renovation profitable, but if only 20% had chosen the maintenance option, the dividend yield would be more feasible in the long run.

The interaction of municipal solid waste incinerator bottom ash (MSWI bottom ash), when utilized as an aggregate in concrete, with the cement matrix was investigated. The most prominent reaction observed in lab and field concrete was the formation of aluminium hydroxide and the release of hydrogen gas from aluminium grains reacting in the alkaline environment. The expansive aluminium reaction was identified as a main cause of extensive spalling on the concrete surface. Due to the higher content of bottle glass as part of the ash, in all samples, reaction products of an alkali-silica reaction (ASR) could be observed as well. However, damage due to ASR were less severe than those caused by the aluminium reaction. The expansion rates were low and only a few of the lab samples showed cracking. Microstructural analysis of the samples indicated clearly that a large quantity of the alkali-silica gel which was formed was accommodated in the pores and voids without exerting any strain on the material.

Modvion develops modular wind turbine towers made of wood. The application requires strong and stiff connections and to achieve the desired performance, a hybrid connection with perforated steel plates slotted into LVL modules is used. The parts will be glued together on site, using a polyurethane adhesive (PUR), providing high strength and stiffness to the connection. This paper presents a preliminary screening on how temperature and relative humidity of the surrounding air during assembly and curing will influence the strength of the bond glued on-site. Static tests were performed on the hybrid connections which were glued and cured in different climates. Tests were also performed at different hardening times to evaluate strength growth in the studied climates. The test results show that at cold temperatures of 9 °C to 12 °C there is a breakpoint where the rate of strength growth starts to decline. The experiments show also that the relative humidity may influence the final strength of the bond. However, the low number of tested specimens brings uncertainties to this observation. High temperatures up to 27 ºC and dry climates down to 20% RH did not impact the strength of the tested hybrid connections.

Measuring deconstructability and reusability of timber buildings. Timber construction must - like all construction - develop towards better resource management. One way to reduce raw material consumption and waste production may be to reuse buildings and building components to a greater extent, and to facilitate this, buildings would need to be designed with that aspect in mind. A European project, InFutUReWood, has investigated how design adapted for reuse can be facilitated and has identified a need for a tool for assessing the deconstructability and reusability of timber buildings. A basic first sketch for an assessment tool was produced, and this study takes the work with the tool further. The overall purpose is to support a development where reuse is considered already in the design phase. More specifically, the project develops a tool to assess how well deconstruction and reuse have been considered in the design of a timber building. The tool is based on the international standard ISO 20887: 2020 and on case studies. The project seeks to answer the questions: What makes deconstruction and reuse easy and what makes it difficult - according to case studies? How can these experiences be considered in the design of the assessment tool? What development needs are there for the sketch of at tool? The work has three thematic parts: 1) Analysis of dismantling and reuse processes in case studies. 2) Analysis of an existing draft of a tool. 3) Assessment of how the tool could be further developed. The general methods of the work are result analysis, interviews, photo documentation and studies of drawings and construction documents. The case studies show several practical ways to achieve dismantling and reusability and illustrate how ISO 20887:2020 can be practically applied. To make the tool suitable for use by an independent party, it needs to be simplified and the assessment criteria processed to be more objective. Clues to how the indicators can be developed are obtained. Continued work includes the involvement of industry to develop criteria that will make them have confidence in the tool. A reformulation and new formulation of indicators in the tool and validation of these is also needed.

The building sector accounts for a large raw material consumption and waste production. One way of diminishing these would be to reuse buildings and building components to a higher degree. To facilitate that, buildings would need to be designed with that aspect in mind. Work Package 2 of the InFutUReWood project investigates new ways to design timber-based structures. This study investigates how new design concepts can be developed to make Villa Anneberg, a two-storey light timber house from the Swedish manufacturer Derome, adapted for deconstruction and reuse. The objectives are: • To identify the inherent strengths and weaknesses of the current design of Villa Anneberg regarding deconstruction, rebuilding and reuse. • To show how the design could be improved with respect to future deconstruction and reuse and to estimate the amount of wood that could be reused in the future with the current and the improved designs. • To suggest guidelines for deconstruction and reuse. • To test and develop a method for carrying out case studies, as the study is the first in a series of case studies treating different structural systems. The study is limited to the load bearing structure of the building. Focus is on reuse rather than recycling. Methods used involve interviews, structured meetings, analyses of drawings and documents, photo documentation and design work. A reuse scenario was assumed where the building will be deconstructed after a few decades into its separate parts. It will then be transported and reassembled to an identical building in the same geographical region. It was found that the current design of Villa Anneberg is relatively well prepared for this scenario already. The building is designed for efficient transport and assembly and the process is judged to be reversible to a high degree. Many connectors are screwed, and the building can be deconstructed with common and simple tools. Several weaknesses were also identified. Among these were joining techniques that are not reversible. Modified versions were developed for three joints. The new solutions were achieved with relatively small adjustments in design and within existing technology. One of the new connections was found so economically valuable to the manufacturer Derome, that it is likely to be taken into production soon. We estimated that the proportion of wood that is reusable would be higher for the modified Villa Anneberg than for the current. The proportion wood that is reusable in the load bearing structure with current design is estimated to 82,7 %. The proportion of wood that is reusable with the modified design is estimated to 86,4 %. These figures apply to the studied scenario. Guidelines for deconstruction and reuse were suggested. The case study method was found efficient and ready to be used in further case studies.

Furniture and furnishings - A technical fire safety guidance – ”the parallelism method” -

This guidance document is funded and distributed by RISE, Research Institutes of Sweden AB. Addressing the fire risks posed by furniture and furnishings is crucial. Swedish fire statistics from 1999 to 2015 record 2264 fire-related deaths, with about 70% occurring in homes and 9% in other buildings. The highest fatality rates are associated with fires starting in beds and upholstered furniture, a pattern seen in many European countries and globally. Despite the significant risk from furniture and furnishings, Swedish regulations remain minimal. Unlike interior construction products, there are no established systems for classification, approval, marking, or market control. As a result, furniture and furnishings often have poor fire performance, potentially leading to rapid and intense fire development in both domestic and public environments. The purpose of this guidance document is to provide a procedure for selecting furniture and furnishings with fire safety levels that align with the fire properties of the surrounding interior materials. It focuses on individual furniture items, using fire test data to match their performance with the fire test data of interior linings. For example, a surface material with a specific Euroclass fire rating can be paired with furniture exhibiting similar fire properties. The aim is to create spaces where both interior items and construction materials exhibit comparable fire behaviour. This approach is referred to in this guidance as the "parallelism method." While this guidance is straightforward to use, it is most effective when applied by individuals with some fire safety expertise who can interpret the recommendations within the context of building regulations or fire safety engineering. Additionally, detailed chapters on fire technical properties and test methods are included to support professionals evaluating fire behaviour, conducting fire modelling, reviewing test reports, or involved in product development. The proposed actions for improving fire safety are based on international fire research and proven experience, as referenced in the guidance. However, the user bears full responsibility for applying the guidance, and the authors disclaim liability for any damages, costs, or issues arising from its use.

AI-baserad säkerhet på byggarbetsplatser har varit ett ett-årigt projekt som genomförts för att förbättra säkerheten på anläggnings- och byggarbetsplatser genom användning av AI-teknologi. Projektet har varit ett samarbete mellan RISE Research Institutes of Sweden, NCC, Ramirent, Skanska och Viscando. Målet var att identifiera och analysera risker på arbetsplatserna med hjälp av sensorer och AI-modeller för att kunna förutsäga farliga situationer och utveckla lösningar för att förbättra säkerheten. Genom observationer, intervjuer och datainsamling med 3D-sensorer analyserades beteendemönster och riskområden på utvalda byggarbetsplatser. Resultaten användes sedan för att  kommunicera och utveckla konkreta lösningar för att minska riskerna. Rapporten ger en översikt av metodologin, datainsamlings- och analysprocessen samt betonar vikten av att förstå både teknologins möjligheter och begränsningar för att skapa en säkrare arbetsmiljö på byggarbetsplatser. 

Although renovation costs can lead to rent increases in energy retrofitting, it is often assumed that reductions in energy costs will counterbalance the rent increase. In Swedish multifamily housing, energy costs for heating are however generally included as a fixed component in the monthly rent, meaning that the rent increase after energy retrofitting corresponds to the net change in rent level as well as energy costs for heating. This makes Sweden a methodologically advantageous setting for studying tenants' cost burden of energy retrofitting. The aim of this study was thus to investigate how energy performance improvement has affected rent increases in Swedish renovation projects between 2013 and 2019. Utilising a national database of multifamily housing, it was found that energy retrofitting entailed a cost relief for tenants in renovation projects with smaller investments. However, in renovation projects with larger investments, energy retrofitting entailed a cost burden for tenants. Moreover, public housing companies had conducted a high share of the extensive energy retrofits, leading to low-income tenant groups being disproportionately subjected to cost burdens of energy retrofitting. On the contrary, light energy retrofits with a cost relief for energy efficiency had been rather evenly distributed across income groups. These results indicate ongoing conflicts with the ability-to-pay principle in the energy transition of Swedish multifamily housing, and suggest that if low-investment energy retrofits are not sufficient for upcoming objectives and requirements, subsidies could be needed to compensate low-income tenants for the cost burden of extensive energy retrofitting. © 2022 The Author(s)

The renovation of buildings involves multidisciplinary issues and multistakeholder involvement, which makes the process complex to manage. The purpose of this paper is to present a transparent, openly accessible, adaptable framework to ensure a sustainable renovation process, covering the technical, environmental, economic, social, and cultural historical aspects to be considered by the various actors during the renovation process. A framework with an associated process was drawn up, focusing on practical usefulness together with the fundamental idea that sustainability cannot be a sub requirement but must be the overall requirement present in all stages of the process. The framework contains an overview, description of activities, links to external tools and documents, and finally a checklist to be completed after each stage. Depending on which stakeholder uses the framework, there are different examples and suggestions for activities and tools. Contrary to many other assessment schemes, the SIRen process focuses on the renovation process itself, and the self-evaluation gives a numerical value that represents to what extent the actors have considered and implemented different aspects of sustainability in the stages of the renovation process. The SIRen process was partially implemented in four renovation projects during the iterative development of the SIRen framework.

This study investigates frame corner joints built of birch plywood plates and glulam elements connected via self-tapping screws. Analytical calculations based on the fastener group’s torsional moment resistance, the proposed fastener group’s elastic and post-elastic load-bearing criteria, and the design formulas in Eurocode 5 were performed to predict the connection capacity in both elastic and post-elastic stages. A combined action check formula was adopted to predict the capacity of birch plywood plates and glulam elements. Frame corner specimens constructed with three different plywood thicknesses were planned to study the influence on global behavior and rotational stiffness. The specimens were intentionally designed so that failure occurred either in plywood or in glulam, in order to examine the robustness and validity of analytical calculation models. Another supplementary test group with 21 mm plywood and fewer fasteners was also designed and tested, in which the plastic yield of fasteners was expected. The test results of this supplementary group served to calibrate the analytical model that predicts the elastic and post-elastic capacity of the connection group. As a result of the comparison, the analytical calculations gave reasonable predictions on the failure of plywood, glulam, and the capacity of the fastener group. Only when the exposed moment exceeded the post-elastic limit of the fastener group did the plastic yielding of fasteners become observable. Moreover, numerical finite element models adopting the foundation zone-modeling scheme were constructed, which were proven to capture all test configurations’ linear loading stiffness satisfactorily. 

Recycled concrete aggregate (RCA) was processed from reinforced concrete edge beams sourced from a demolished bridge. This material replaced different ratios of coarse aggregate in a benchmark concrete. The tensile behavior of the developed concrete mixes was characterized via monotonic and cyclic uni-axial tensile tests performed on notched cylinders. Such tensile tests allow for the quantification of the fracture energy and softening behavior of the concrete. Moreover, acoustic emission (AE) measurements were conducted in conjunction with the cyclic tests to characterize e.g. micro-crack initiation and development, as well as crack localization. The tensile behavior of the various materials was found to be similar with minimal variation in the results. However, the softening behavior suggests that the RCA materials are slightly more brittle compared to both the mother and benchmark materials. The corresponding AE measurements also indicated similarities between the micro-crack initiation and development for these mixes. It can be constituted that if the concrete used to produce RCA is of high quality and from one source, the resulting RAC will have adequate tensile properties with minimal variation, despite the aggregate replacement ratio.

Assessment of the presence of hazardous materials in buildings is essential for improving material recyclability, increasing working safety, and lowering the risk of unforeseen cost and delay in demolition. In light of these aspects, machine learning has been viewed as a promising approach to complement environmental investigations and quantify the risk of finding hazardous materials in buildings. In view of the increasing number of related studies, this article aims to review the research status of hazardous material management and identify the potential applications of machine learning. Our exploratory study consists of a two-fold approach: science mapping and critical literature review. By evaluating the references acquired from a literature search and complementary materials, we have been able to pinpoint and discuss the research gaps and opportunities. While pilot research has been conducted in the identification of hazardous materials, source separation and collection, extensive adoption of the available machine learning methods was not found in this field. Our findings show that (1) quantification of asbestos-cement roofing is possible from the combination of remote sensing and machine learning algorithms, (2) characterization of buildings with asbestos-containing materials is progressive by using statistical methods, and (3) separation and collection of asbestos-containing wastes can be addressed with a hybrid of image processing and machine learning algorithms. Analysis from this study demonstrates the method applicability and provides an orientation to the future implementation of the European Union Construction and Demolition Waste Management Protocol. Furthermore, establishing a comprehensive environmental inventory database is a key to facilitating a transition toward hazard-free circular construction