Hoe kun je als eigenaar, potentiële koper, ontwikkelaar of investeerder weten of een leegstaand kantoorgebouw geschikt is voor herbestemming naar woningen, en of dit functioneel, technisch en financieel haalbaar is? Een belangrijke vraag, zeker in een periode van veel leegstand en een grote vraag naar woningen. Dit hoofdstuk bespreekt de zogenoemde transformatiemeter, een checklist waarmee kan worden bepaald welke kenmerken van de markt, de locatie, het gebouw en betrokken partijen gunstig of ongunstig zijn voor succesvolle transformatie, mogelijke risico’s en hoe deze risico’s gereduceerd kunnen worden. De transformatiemeter is gefaseerd van snel en globaal naar meer gedetailleerd. Voorts wordt de rol van dit instrument besproken in de besluitvorming over een go/no-go: doorgaan met verdere planontwikkeling, of stoppen met onderzoek naar haalbaarheid. Het hoofdstuk sluit af met een korte bespreking van enkele andere instrumenten om de kansen, obstakels en risico’s van herbestemming in kaart te brengen.

Building owners and other stakeholders can adopt different strategies to cope with vacancy, such as consolidation, rent reduction, selling the building, renovation, transformation and conversion to adapted reuse, or demolish and build a new building. This chapter discusses various tools to cope with vacancy by adaptive reuse. It presents an overview of the many factors and aspects that enable or hinder adaptive reuse by conversion of (office) buildings into housing, and how to assess the characteristics of the market, location, building and involved stakeholders. Furthermore, it presents the Conversion Meter, a tool to assess the conversion potential of vacant office buildings into housing. The tool is built up from a first quick scan using veto criteria (Step 1) till a more detailed scan of the conversion potential based on gradual criteria (Step 2). No single gradual criterion is sufficient to decide if conversion is possible or not; it is the combination of all criteria i.e. the sum that provides a valuable indicator for the conversion potential. Step 3 calculates a conversion potential score as a weighted sum of all criteria. Step 4 is a scan on financial feasibility. The final Step 5 is a check on possible risks and opportunities to eliminate these risks. The chapter continues with lessons learned from case studies by applying the Conversion Meter.

The high vacancy rate in the office building market in the Netherlands is mainly explained by an overproduction of office space. The demand is expected to decrease further due to aging of the population, a changing economy and the decreasing need for space. A possible new end-user is the creative industry. The different working standards of this industry lead to different use of office space than the large-scale offices of the production economy. Adaptive reuse can create a solution for the need of new accommodations in this part of the office market. In this research a strategy has been developed that explains which characteristics a vacant office building must meet to be reused for the creative industry, which facilities it must offer and how tenants should be selected and managed. The possibilities have been researched by a detailed literature research, three in-depth case studies with successful redevelopments for the creative industry in Eindhoven, Rotterdam and Amsterdam and interviews with several experts in practice.

The high vacancy rate in the office building market in the Netherlands is mainly explained by an overproduction of office space. The demand is expected to decrease further due to aging of the population, a changing economy and the decreasing need for space. A possible new end-user is the creative industry. The different working standards of this industry lead to different use of office space than the large-scale offices of the production economy. Adaptive reuse can create a solution for the need for new accommodations in this segment of the office market. In this research, a strategy has been developed that explains which characteristics a vacant office building must meet to be reused for the creative industry, which facilities it must offer and how tenants should be selected and managed. The possibilities have been researched by a detailed literature research, three in-depth case studies with successful redevelopments for the creative industry in Eindhoven, Rotterdam and Amsterdam and interviews with several experts in practice.

This chapter first discusses the state of the art regarding the concepts of adaptability and flexibility and the need for adaptable buildings. Then it presents possible benefits and sacrifices of typical interventions, The next section discusses ways to measure the adaptability capacity of buildings and includes both a long list and a short list of KPIs. The assessment criteria for adaptability are based on previous research by Geraedts and Van der Voordt, 2007; Remøy and Van der Voordt, 2007; Wilkinson et al., 2009; DGBC, 2013; and Geraedts and Remøy, 2014. The chapter ends with some suggestions for further research.

Building owners and other stakeholders can adopt different strategies to cope with vacancy, such as consolidation, rent reduction, selling the building, renovation, transfor-mation and conversion to adapted reuse, or demolish and build a new building. This paper dis-cusses a new developed tool to cope with vacancy by adaptive reuse. It presents an overview of the many factors and aspects that enable or hinder adaptive reuse by conversion of (office) buildings into housing, and how to assess the characteristics of the market, location, building and involved stakeholders. It presents the Conversion Meter, formerly known as the Transfor-mation Meter, a tool to assess the conversion potential of vacant office buildings into housing.

Adaptive construction is already for decades on the agenda of the construction sector. The adaptive capacity of a building includes all qualities that enable the building keeping its functionality during the technical life cycle, under altered conditions and needs [1]. Meanwhile, the interest in flexible building has increased significantly caused by the growing awareness of the need for sustainability. The Dutch construction sector is responsible for 35% of the national waste production. This number emerges from a sector that accounts for 5.1% of the gross domestic product [2]. This paper reports about a study that was executed in collaboration with a Dutch real estate developer [3]. The purpose was to develop a successful business case for a flexible row house concept that could show the market under what conditions flexibility measures for future adaptations can be implemented. One of the main conclusions affirms that a long-lasting collaboration between a developer and the investor could result in a feasible business case if the developer stays involved during the use phase of the dwellings. Through many additional interviews, this research was able to let the real estate market reflect about the business case of flexible row housing.

The high vacancy rate in the office building market in the Netherlands is mainly explained by an overproduction of office space. The demand is expected to decrease further due to aging of the population, a changing economy and the decreasing need for space. A possible new end-user is the creative industry. The different working standards of this industry lead to different use of office space than the large-scale offices of the production economy. Adaptive reuse can create a solution for the need of new accommodations in this part of the office market. In this research a strategy has been developed that explains which characteristics a vacant office building must meet to be reused for the creative industry, which facilities it must offer and how tenants should be selected and managed. The possibilities have been researched by a detailed literature research, three in-depth case studies with successful redevelopments for the creative industry in Eindhoven, Rotterdam and Amsterdam and interviews with several experts in practice.

The adaptive capacity of buildings is considered to be a crucial component when looking into the sustainability of the real estate stock (Hermans e.a., 2014). Market developments show increased demands for flexibility and sustainability by users and owners of buildings. Since 2014 a research project at the Delft University of Technology has been investigating the adaptive capacity of buildings. One of the interim results included an instrument to assess the adaptive capacity of buildings. The last version of this instrument FLEX 4.0 was presented in detail at the SBE16 Tallinn Conference, Build Green and Renovate Deep (Geraedts, 2016), including all flexibility key performance indicators. Another important research question to be answered in this continuous research project was: “Which flexibility measures have been actually used in practice by the (re)developers of office buildings”? To answer this question use has been made of all possible flexibility measures from the described FLEX instrument. The implementation of these possible flexibility measures was discussed with experts from practice and finally two in-depth case studies were performed in Amsterdam (Tuzgöl, 2016). This paper presents the final results of this research. They have led to a specific advice to project developers which flexibility measures should be applied at all times, which measures have been barely or not used at all in practice and therefore not recommended to apply, and finally which measures have not been applied but however desired by the project developers.

The Dutch office market has a big vacancy problem with a high vacancy rate. Also can be noticed an increasing shortage for student housing in university cities. Transformation of vacant office buildings into student housing could be a potential sustainable solution to partially solve both problems. This research project provides an overview of all relevant aspects needed for the decision process, especially in the initiative phase of these transformation projects. The aspects related to transformation into student housing are clustered in five main themes as a success factor or as a possible bottleneck. Success factors and bottlenecks that affect this type of transformation have been researched through an extensive literature survey, expert interviews and three in-depth case studies. The results of this research have led to a useful tool that assists project developers in the initiative phase to consider the transformation potential of a specific project. The outcome also allows developers to discuss relevant aspects and visually convinces other actors involved in this complex process.

Adaptive buildings are green buildings. But the question is: how to measure green? A direct connection can be made between adaptive building and sustainability. Market developments show increased demands for flexibility and sustainability by users and owners as well as a growing understanding of the importance of a circular economy. Since 2014 a research project at the Delft University has been investigating the adaptive capacity of buildings. As one of the results several versions of an instrument to assess the adaptive capacity of buildings have been developed since. The last version FLEX 4.0, amongst others based on the support and infill theory of Habraken [1], is described in detail in this paper, including all flexibility key performance indicators, the different default weighting factors, their assessment values and some examples to determine the flexibility class of buildings. This paper thus presents a complete assessment instrument that can be used in practice.

Market developments show increased demands for flexibility and sustainability by users and owners of buildings. A direct connection can be made between adaptive building and sustainability. The longer a building can keep its functional life cycle instead of becoming vacant or being demolished, the more sustainable a building will be. One way of looking into this phenomenon is the more a building is flexible and able to adapt to changing user demands, the longer it will keep its functional life cycle. In 2014 a paper was presented at the International Union of Architects World Congress UIA2014 in Durban SA, titled Adaptive Capacity of Buildings. A report was given of an extensive international literature survey and the development of a method to determine the adaptive capacity of buildings. In total 147 flexibility indicators were described with accompanying assessment values. The most important recommendation for the next step was the development of an easy to use assessment method in practice with a limited number of important adaptability performance indicators.
Further research led in 2015 to a renewed assessment method with 83 indicators, clustered in five layers with different life cycles. This method was called FLEX 2.0 and a derived version was called FLEX 2.0 LIGHT with only 17 of the most important indicators. This was presented in 2015 at the CIB Conference - Going North for sustainability in London. At the same time this method was used in two separate research projects for an evaluation with experts in practice. One research project concerned the development of school buildings; the other project was related to the development of office buildings. The main conclusions and recommendations of both research projects to evaluate the FLEX 2.0 method in practice with two different types of real estate will be described in this paper. Questions will be answered about the differences and similarities between the two different categories of real estate when using this flexibility assessment method. This will lead to some important conclusions for the next version of the method: FLEX 3.0. Finally a renewed framework for this next version will be presented.