Renovation Strategies for Multi-Residential Buildings from the Record Years in Sweden—Profit-Driven or Socioeconomically Responsible?

An important part of the multi-family housing stock in Sweden was built during the record years 1961–1975 and is in need of extensive renovation to be modernized. The stock is also at the center of political discussion of how to sustain ‘good housing for all’, especially in the rental sector. These renovation needs coincide with present energy targets and provides an opportunity to combine renovation with energy efficiency measures. Common for many of these buildings are that neglected maintenance has led to technical shortcomings, such as high energy use and low thermal comfort due to bad insulation, unsatisfactory air tightness and leaky windows, inefficient heating systems and insufficient ventilation, and moisture damage due to leaking building envelope and leaking pipes. However, the people living in these buildings are not willing to or cannot afford to pay the higher rents that extensive renovations would entail. Earlier research has highlighted the broader societal problem of energy renovations, but also that of housing companies’ priority of measures with short payback times, and those that give the possibility to raise rents. However, recent observations indicated a tendency towards more holistic approaches to housing renovation, and this study was initiated to investigate how public and private housing companies deal with renovation levels, rent increases and related social problems. The main conclusions are that sustainability and social responsibility are moving up on agendas in the public sector, but also, apparently, in the renovations strategies among the private companies. What is also seen is a trend moving from extensive total renovations to more tenant-adapted and step-by-step renovations. Renovation options which do not entail such large rent increases are increasingly being seen. Implications are that housing owners favor gentle renovation with reasonable rent increases of 10%–20%, which at the same time, may be a drawback for reaching energy efficiency targets

Renovating on Unequal Premises: A Normative Framework for a Just Renovation Wave in Swedish Multifamily Housing

While the energy transition of the EU housing stock is now being intensified with the launch of the Renovation Wave, economic inequalities are increasing in many OECD countries, which has effects on housing-related inequalities and the demand of affordable housing. The Renovation Wave is thus an opportunity to improve housing quality for low-income households, but also entails risks for increased rents. In Sweden, the standard of housing is relatively high and energy poverty in multifamily housing is rare, meaning that there are limited social benefits to be achieved from extensive energy retrofitting; moreover, Sweden lacks a social housing sector, which limits protection of the worst-off residents. This paper thus explores whether the limited social benefits of the Renovation Wave weigh up against the risks that it entails for the worst-off in the Swedish context. This is done within a normative framework for just energy transitioning that is developed within the context of the Renovation Wave and increasing economic inequalities, consisting of four ordered principles: (1) The equal treatment principle; (2) The priority principle; (3) The efficiency principle; and (4) The principle of procedural fairness. Analysis showed that to be considered just according to our framework, the Swedish energy transition of housing should, in contradistinction to what is suggested in the Renovation Wave, limit the imposition of extensive energy retrofitting in low-income areas. Finally, having identified a mismatch between the most effective approaches in terms of energy savings and the most acceptable approaches in terms of social justice, we offer policy recommendations on how to bridge this mismatch in a Swedish context

Moisture Conditions in High Performance Concrete. Mathematical Modelling and Measurements

The work presented in this thesis has been focused on developing a model to calculate the moisture conditions in concrete of low water/binder ratio (W/B) which is normally used in high performance concrete. To do this, the moisture conditions in high performance concrete have been studied, from a very early age. The separate processes involved have been clarified and combined into a complete model. The main processes are the chemical and physical binding of moisture in the concrete and the moisture flow through the concrete. Since self-desiccation is of great importance for concrete of low W/B, this has been studied separately and a model for self-desiccation has been developed which represents an important part of the model for moisture conditions in high performance concrete. In order to describe the moisture conditions in concrete a number of material properties were required. These have been determined from literature studies and from laboratory measurements. For example, the influence of curing conditions on the rate of reaction has been studied by measuring the degree of reaction of binders in concrete stored at different levels of RH at low ages. The desorption isotherms for a few different concrete compositions at different age of maturity have been measured and also moisture transport properties of high performance concrete have been measured at very early age. A calculation model for estimating the moisture conditions in concrete structures subjected to certain curing and climatic conditions has been developed. This model takes both self-desiccation and moisture transport into consideration. The model has been used to simulate the moisture conditions in real concrete structures subjected to different climatic conditions and the results from the model agree reasonably well with measured data, except for concrete submerged under water where the measured data are much lower than the calculated. The reason is probably that there are other phenomena involved, that are not included in the calculation model, causing the dry moisture conditions inside the concrete structure

Moisture Conditions in High Performance Concrete. Mathematical Modelling and Measurements

The work presented in this thesis has been focused on developing a model to calculate the moisture conditions in concrete of low water/binder ratio (W/B) which is normally used in high performance concrete. To do this, the moisture conditions in high performance concrete have been studied, from a very early age. The separate processes involved have been clarified and combined into a complete model. The main processes are the chemical and physical binding of moisture in the concrete and the moisture flow through the concrete. Since self-desiccation is of great importance for concrete of low W/B, this has been studied separately and a model for self-desiccation has been developed which represents an important part of the model for moisture conditions in high performance concrete. In order to describe the moisture conditions in concrete a number of material properties were required. These have been determined from literature studies and from laboratory measurements. For example, the influence of curing conditions on the rate of reaction has been studied by measuring the degree of reaction of binders in concrete stored at different levels of RH at low ages. The desorption isotherms for a few different concrete compositions at different age of maturity have been measured and also moisture transport properties of high performance concrete have been measured at very early age. A calculation model for estimating the moisture conditions in concrete structures subjected to certain curing and climatic conditions has been developed. This model takes both self-desiccation and moisture transport into consideration. The model has been used to simulate the moisture conditions in real concrete structures subjected to different climatic conditions and the results from the model agree reasonably well with measured data, except for concrete submerged under water where the measured data are much lower than the calculated. The reason is probably that there are other phenomena involved, that are not included in the calculation model, causing the dry moisture conditions inside the concrete structure

Milparena – A Network Project for Knowledge Enhancement Regarding Energy Renovation of Multi-family Buildings in Sweden

There are ambitious goals and increased efforts to reduce the use of energy in existing buildings. However, so far most efforts have been and are still related to new “low energy buildings”. This paper is focused on the conditions related to existing Swedish multi-family buildings with rented apartments primarily owned by municipal housing companies. It describes the work within a network with representatives from a university and a large research institute working together with municipal housing companies to enhance the knowledge about the framework for energy renovation of multi-family buildings. It has a holistic approach and the main results are as follows. On one hand, most housing company managers believe it is too complicated or unreasonably expensive to execute a comprehensive energy renovation. On the other hand, too many stakeholders focus on the technical issues, e.g. so called innovative technologies, while economic and organizational matters in most cases are more important to tackle. It is possible to achieve a large reduction of the energy use with existing (expert) knowledge and state-of-the-art technologies, but there are so far too poor incentives for a comprehensive reduction of the energy use in existing Swedish multi-family buildings

Utmaningar vid planering av h\ue5llbar bostadsf\uf6rnyelse: En studie av ett miljonprogramsomr\ue5de

M\ue5nga bostadsf\uf6retag st\ue5r inf\uf6r renovering och f\uf6rnyelse av miljonprogrammets bostads-omr\ue5den. Det finns tekniska behov av upprustning, och nationella m\ue5l om energibesparing-ar. Samtidigt \ue4r det m\ue5nga bostadsomr\ue5den d\ue4r de boende har en l\ue5g betalningsf\uf6rm\ue5ga f\uf6r de \uf6kade utgifter som en renovering kan medf\uf6ra. Utmaningar vid renovering av miljonprogrammet har utpekats tidigare men f\ue5 studier har ing\ue5ende f\uf6ljt processen d\ue5 en renovering genomf\uf6rs. Den h\ue4r rapporten beskriver en l\ue5ng och inneh\ue5llsrik process d\ue4r ett allm\ue4nnyttigt Bostadsf\uf6retag planerar f\uf6r en renove-ring av ett bostadsomr\ue5de i stadens utkanter. Studien belyser processens olika steg, hur beslut tas och m\ue5l formuleras, samverkan och konflikter mellan v\ue4rden, m\ue5l och medver-kande samt unders\uf6ker m\uf6jligheten f\uf6r aff\ue4rsmodeller f\uf6r en h\ue5llbar renovering. Studien bygger p\ue5 intervjuer, observationer och deltagande vid m\uf6ten och aktiviteter. Fr\ue5n att ha projekterat f\uf6r en st\uf6rre dyrare omvandling av den befintliga bebyggelsen landar Bostadsf\uf6retaget i planer f\uf6r en mindre omfattande insatts begr\ue4nsad till klimatskalet och utemilj\uf6n. Under processens lopp sker m\ue5nga omstarter som b\ue5de \ue4r kostsamma och slitsamma f\uf6r f\uf6retagets personal. Projektet har saknat en tydlig m\ue5lbild och f\uf6rankring i det egna f\uf6retaget och bland de boende. Dialogarbetet kom ig\ue5ng f\uf6rst en bit in i processen och efter flera omstarter. Personalen har bytts ut under projektets g\ue5ng samtidigt som det har saknats dokumentation fr\ue5n de tidigare skedena i processen. Projektets f\uf6ruts\ue4ttningar har ocks\ue5 \ue4ndrats under processens g\ue5ng, bland annat genom nya politiska direktiv om m\uf6jligheten att bo kvar efter en renovering. Stadsdelen \ue4r av staden utpekad som ett prioriterat omr\ue5de f\uf6r utveckling och kommunen har efterlyst en helhetssyn kring utvecklingen och ett samarbete mellan stadens olika bolag och kontor. Fr\ue5n Bostadsf\uf6retagets sida har det funnits f\uf6rhoppningar om en st\uf6rre utveckling av stadsdelen som skulle kunna lyfta omr\ue5det och g\uf6ra det attraktivt f\uf6r nya investeringar. Den planerade renoveringen var t\ue4nkt att ske parallellt med nyproduktion i omr\ue5det. Samarbetet mellan dessa akt\uf6rer har varit sv\ue5r att genomf\uf6ra i praktiken. Slutsatser fr\ue5n studien summeras i ett antal rekommendationer avseende behovet: att styra upp renoveringsprocessen, definiera ramar och st\ue4lla upp m\ue5l och delm\ue5l, dokumentera, att anv\ue4nda befintliga verktyg och kunskap, samt tilldela ansvar och roller. Vidare lyfts det positiva i att involvera de boende fram. Slutligen presenteras ett f\uf6rslag p\ue5 en modell f\uf6r att skapa en aff\ue4r av renoveringen baserad p\ue5 v\ue4rdeskapande aktiviteter. \uc4ven om slutsatser-na enbart bygger p\ue5 ett fall bed\uf6ms de ha ett allm\ue4nt v\ue4rde d\ue5 m\ue5nga bostadsf\uf6retag och bostadsomr\ue5den st\ue5r inf\uf6r liknande utmaningar vid renovering