Estimating the probability distributions of radioactive concrete in the building stock using Bayesian networks

The undesirable legacy of radioactive concrete (blue concrete) in post-war dwellings contributes to increased indoor radon levels and health threats to occupants. Despite continuous decontamination efforts, blue concrete still remains in the Swedish building stock due to low traceability as the consequence of lacking systematic documentation in technical descriptions and drawings and resource-demanding large-scaled radiation screening.The paper aims to explore the predictive inference potential of learning Bayesian networks for evaluating the presence probability of blue concrete. By integrating blue concrete records from indoor radon measurements, pre-demolition audit inventories, and building registers, it is possible to estimate buildings with high probabilities of containing blue concrete and encode the dependent relationships between variables. The findings show that blue concrete is estimated to be present in more than 30% of existing buildings, more than the current expertassumptions of 18–20%. The probability of detecting blue concrete depends on the distance to historical blue concrete manufacturing plants, building class, and construction year, but it is independent of floor area and basements. Multifamily houses and buildings built between 1960 and 1968 or nearby manufacturing plants are more likely to contain blue concrete. Despite heuristic, the data-driven approach offers an overview of the extent and the probability distribution of blue concrete-prone buildings in the regional building stock. The paper contributes to method development for pattern identification for hazardous building materials, i.e., blue concrete, and the trained models can be used for risk-based inspection planning before renovation and selective demolition

ByggaF - A Method to Include Moisture Safety in the Construction Process

ByggaF is a methodology for including moisture safety in the construction process that was developed and presented in 2007. ByggaF comprises methods to secure, document and communicate moisture safety throughout the construction process, from planning to management. The methods involve a standardized way of working designed to meet the demands of society and the client’s requirements for moisture safety. On request from the Swedish construction sector, ByggaF has been transformed into an industry standard. Since then, ByggaF has been used in a number of Swedish construction projects. One reason for the broad implementation of ByggaF is that the Swedish environmental assessment tool Miljöbyggnad demand for using ByggaF in order to reach “silver level” or “gold level”. Another reason is that more than 100 moisture experts have been trained to use ByggaF to assure a moisture safe building process. There has also been interest in using ByggaF expressed from other countries. The industry standard has been translated to English but it needs to be adjusted to country specific conditions, such as regulation and building practices in order to be applied in other countries. In Finland, the Swedish version of ByggaF has been adapted to Finnish regulations and used for including moisture safety in construction of a school at Bergö. There have also been attempts to adjust ByggaF to suit specific applications such as construction of prefabricated single family houses and renovation of multifamily houses

Data-driven prediction of PVC flooring in the Swedish building stock

PVC flooring accounts for a significant share of PVC use in the construction sector and has great potential for recycling. Nevertheless, the actual recycling rate of PVC flooring spillage in 2018 was less than 20%, according to the national system for the separate collection and recycling of material residues from the installation of PVC floorings, developed by flooring manufacturer Tarkett AB and now used by all manufacturers in the flooring industry. To improve the sorting and recycling process of old PVC flooring it is necessary to identify where the material is located and evaluate its recycling potential. Such information is crucial for demolition waste recycling companies and flooring manufacturers to improve recycling practices for PVC flooring and then use the recycled PVC materials in the new flooring production. The challenge is to find out in which buildings there is PVC flooring and when it was installed which will indicate when it is planned to be dismantled and replaced. Since the PVC flooring manufactures do not keep track on where their products are laid such information is lacking. The best source of information that was made available for the researchers appeared to be the public building owners´ maintenance plans. Therefore, it was decided to focus on the presence of PVC flooring in public preschools as an example. By combining data from maintenance plans with national building registers, the PVC flooring in the Swedish preschools have been forecasted. The project results show an example how limited data sources can be used to predict presence of materials in larger stocks and is therefore expected to contribute to a climate-neutral supply chain with recycled PVC flooring. Based on the results of this study, dialogue, recommendations and guidelines can be developed for the flooring industry, the waste and recycling industry and the Swedish real estate and construction sector.The project has been financed with support from Vinnova, the Swedish Innovation Agency.</p

SIREN: A Comprehensive Framework for a Sustainable Renovation Process with a Holistic Approach

A comprehensive framework for a sustainable renovation process with a holistic approach to renovation has been developed, taking into consideration the areas: technology, environment, economy, social values, and architecture and cultural historical environment. The framework describes activities that should be carried out at different stages of the process, as well as charting who will be responsible for and performing these activities. The framework refers to available methods, tools and procedures that can be used for inventories of existing buildings, analyzes of renovation options and supporting decisions of which measures to take in the different stages of the renovation process to include all aspects that are essential for achieving sustainable refurbishment. After each stage (planning, design, reconstruction and commission) in the renovation process a self-evaluation can be made to estimate to what extent each sustainability aspect has been considered and included

Moisture safety of wooden buildings – design, construction and operation

During the last decade, building in wood has increased, mainly due to environmental awareness and targets to decrease the carbon footprint originated from the production of building materials. New technologies such as CLT (cross laminated timber) have accelerated the construction of multi-story wooden buildings. The CLT structure has been used both for housing and offices. Due to the extensive size of the buildings and relatively fast assembly of the buildings, weather protection has not always been used. It is commonly known that building materials sensitive to moisture need to be protected against high moisture conditions and water during construction. If this is not done, there is an increased risk of microbial growth which can result in health problems for future users of the building, extensive costs for the remediation and exchange of materials, but also lack of trust in the construction industry. There are disagreements between the building industry and researchers how sensitive wooden buildings are to exposure to high moisture levels and water during storage at sites and construction. Based on results from several research projects studying moisture conditions both in the laboratory and in the field, recommendations for procurement, storage and handling of wood during construction to assure moisture safety are suggested in this paper

Application of a Decision Support Tool in Three Renovation Projects

Building owners are encouraged to reduce energy use in order to both contribute to national energy-saving goals and reduce the costs of heating and operation. It is important to choose the most optimal renovation measures available so as to achieve cost-effective energy use while maintaining excellent indoor environments, without sacrificing architectural quality or negatively affecting the environment. Building owners and managers often have neither the time nor the expertise required to properly evaluate the available renovation options before making a final decision. Renovation measures are often calculated to repay investments in a short time, rather than taking into account life-cycle costs (LCC), despite the fact that a thoughtful, comprehensive renovation is often more cost-effective in the long run. This paper presents a systematic approach for evaluating different renovation alternatives based on a number of sustainability criteria. The methodology has been verified using three multi-family apartment buildings in Sweden. The benefit of using the proposed methodology is made clear through a comparison between the different renovation alternatives from a sustainability perspective, and will hopefully serve as encouragement to choose renovation measures which involve marginally increased investments but lead to significant environmental and social benefits in the long-term

Swedish public and private housing companies’ access to the capital market for financing energy renovation

The financing of energy efficiency measures and renovations is key to reaching energy efficiency targets for the housing sector. The purpose of this article is to add the Swedish case of how capital market funds have become accessible and used by public and private housing companies, in particular for energy efficiency measures. The core of this article are interviews with representatives of Swedish housing companies made during the spring of 2021 with the purpose of mapping how public and larger private housing companies finance renovation and energy efficiency measures, and to what extent funds from the capital market are used for these purposes. In this article, we have found that capital market funds are commonly used by the Swedish public and the largest private housing companies. Bonds are less costly compared to bank loans, and green bonds are 0.02–0.03 percentage points less costly than conventional bonds. Furthermore, control systems that investigate the values of building portfolios as security for bonds are poor. A conclusion is that governmental control systems over the capital market issuing bonds for the housing market could be needed to avert future housing bubbles

Genomlysning branschstandard för fuktsäker byggprocess

Denna genomlysning av Branschstandard ByggaF – metod för fuktsäker byggprocess hargjorts med målet tydliggöra den fuktsäkerhetsprocess som krävs för att säkerställafuktsäkra byggnader och med speciell hänsyn till det tänkta nya formatet i projektetMöjligheternas Byggregler.Arbetet har utförts av en grupp personer som representerar olika aktörer i byggsektorn ochsom är väl förtrogna med Branschstandard ByggaF och flera använder den dagligen.Arbetet som genomförts under en kort och intensiv period har präglats av ett stortengagemang och vilja att bidra till förbättring och anpassning av Branschstandard ByggaFtill nya förutsättningar och behov.Det är viktigt att betona är att det här är en genomlysning som ska visa påutvecklingsbehov av Branschstandard ByggaF utifrån de kommande förändringarna ibyggreglerna. Genomlysningen har visat på delar som inte fungerar så bra i praktiken ochsom behöver revideras och vidareutvecklas. Uppdraget omfattar inte att ta fram en nyreviderad Branschstandard ByggaF men förbättringsförslag har identifierats under rubriken“önskat läge”. Arbetsgruppen har många tankar om vad som borde revideras i nuvarandeBranschstandard ByggaF och i nästa steg, när det faktiska arbetet ska göras medrevideringar kan det behövs göras andra ändringar än vad som föreslås här. Detta är baraett förslag.Det är dock viktigt att poängtera att det som återges här inte är något färdigt förslag ochinte alltid arbetsgruppens gemensamma åsikt (koncensus) utan mer exempel på möjligautvecklingsriktningar. Trots att arbetsgruppen försökt nå konsensus har det funnits liteolika synsätt på vissa detaljfrågor.