How can an owner, potential buyer, developer, or investor know if a vacant office building is suitable for conversion to housing and to what extent this is functionally, technically, and financially feasible? This is an important question, especially in a time of high vacancy rates and a strong demand for housing. This chapter discusses the so-called transformation meter, also called a conversion potential assessment tool: a checklist that helps determine which characteristics of the market, location, building, and involved parties are favourable or unfavourable for a successful transformation, potential risks, and how these risks can be mitigated. The transformation meter is phased from a “quick and dirty” general assessment to a more detailed analysis. Additionally, the role of this tool in the decision-making process regarding a go/no-go decision—whether to proceed with further planning or to stop investigating feasibility—is discussed. The chapter concludes with a brief discussion of other tools available for assessing the opportunities, obstacles, and risks associated with repurposing buildings.

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 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.

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.

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.

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.

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.

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.

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.

In the Netherlands, both the office market and housing market show a mismatch between supply and demand, quantitatively and qualitatively. In 2007 almost 14% of all offices are vacant, i.e. 5.9 million square meters. At the same time we see a shortage of about 1 million dwellings. A building must be able to be changed over its life cycle to adapt to the inevitable evolving needs of it’s end users. The first real challenge is how to make adaptable buildings without creating unnecessary redundancy. The second challenge is the re-use of old vacant buildings because the available area for erecting new ones is very scarce in the Netherlands. In this matter, old buildings deserve a second chance in their life cycle. We need to be able to measure the transformation potential of office buildings both at location and at building level. To this end, we have developed what we call a ‘transformation potential meter’ (Geraedts, Van der Voordt, 2003, 2004). The meter has been tested since 2004 in practice by a number of market players, and by students of architecture. This has allowed the transformation potential meter to be evaluated and refined in 2006. Two new steps - the financial feasibility scan and the risk assessment checklist – have also been added. In this paper, we describe the principle of the new transformation potential meter.

In zijn bijdrage over de gelaagdheid van leegstand pelt Willem Keeris de leegstand af tot het niveau waarop leegstand echt problematisch is en transformatie een interessante optie kan zijn. Aanloopleegstand, mutatieleegstand en frictieleegstand moeten als een normaal onderdeel van het verhuurproces worden beschouwd, aldus Keeris. De echte problemen zitten in langdurige leegstand die de fase van frictieleegstand overschrijdt, operationele leegstand door een laag prestatieniveau, en kansarme/kansloze structurele leegstand. Een belangrijke vraag is of hierop valt te anticiperen. Is het mogelijk om te voorspellen welke kantoorgebouwen als eerste in de gevarenzone komen, wanneer het aanbod aan kantoorruimte de vraag naar kantoorruimte overtreft? Welke kenmerken van de markt, de locatie en het gebouw zijn hierin doorslaggevend? Hoe kan op getrapte wijze, van quick-and-dirty naar grondig en gedetailleerd, een scan plaatsvinden van de kantorenvoorraad op het vroegtijdig signaleren van dreigende leegstand en het vaststellen van potenties en risico’s van behoud als kantoorgebouw?

Om op een efficiënte en systematische manier te kunnen vaststellen of een leegstaand of leegkomend kantoorgebouw voldoende potentie heeft om te worden omgebouwd tot woningen, is de zogenaamde Transformatiepotentiemeter ontwikkeld (Geraedts en Van der Voordt, 2000, 2003). Kort gezegd is dit een checklist met vetocriteria en graduele criteria, waarmee kan worden bepaald welke kenmerken van de locatie en het gebouw gunstig of ongunstig zijn voor succesvolle transformatie. Snel en globaal (Quick Scan) of meer gedegen en gedetailleerd (Haalbaarheidscan). De meter is door verschillende marktpartijen in de praktijk toegepast. Ook afstuderende bouwkundestudenten hebben er veelvuldig gebruik van gemaakt. Zoals het goede studenten betaamt, hebben zij het instrument kritisch tegen het licht gehouden. Zie hiervoor onder meer de afstudeerscripties van Nicole de Vrij, Klaas Jan Boer, John Magielsen, Kawai Pang en Niels Jongeling. Op basis van de toetsing in de praktijk is de oorspronkelijke Transformatiepotentiemeter geëvalueerd en verbeterd. Toegevoegd zijn twee nieuwe stappen: Scan financiële haalbaarheid en Checklijst risico’s planvorming. Hiermee kan de haalbaarheid van een transformatieproject verder onderzocht worden. In dit hoofdstuk beschrijven we de nieuwe Transformatiepotentiemeter en positioneren we dit instrument in de besluitvorming over een GO/NO GO in de initiatieffase. Voor deze bijdrage zijn interviews gehouden met bij transformatie betrokken partijen in Nederland. Aan hen is onder meer de vraag voorgelegd, welke aspecten zij op locatie- en gebouwniveau het meest belangrijk vinden voor een kansrijke transformatie. Verder is gebruik gemaakt van uitkomsten uit onderzoek naar woonwensen in relatie tot locatie- en gebouwkenmerken.

In the Netherlands, both the office market and housing market show a mismatch between supply and demand, quantitatively and qualitatively. In 2007 almost 14% of all offices are vacant, i.e. 5.9 million square meters. Experts judge at least 1 million m2 as having no chance at all to be let again as an office. At the same time we see a shortage of about 1 million dwellings. This paper discusses opportunities and risks of converting empty offices into houses. A checklist will be presented that can be used to support the decision whether or not starting a transformation process and a number of go/no go decisions later on. This checklist is partly based on a literature survey on user requirements and preferences with respect to office accommodation and housing, and partly on interviews with parties involved in transformation processes in the Netherlands. The interviewees were asked which features of locations and buildings they considered to be most relevant. An earlier draft of the method has been tested in practice by market players and students of architecture. The five steps method - from quick and dirty to a more thorough, detailed study - include an analysis of the local market and critical characteristics of the location and the building(s), an economic feasibility study and a check on a number of risk factors from a functional, architectonical, juridical and technical point of view. Using veto criteria and gradual criteria, the method shows which features of the location and the building favour successful transformation, and which hinder it.

It is important to have an effective means of determining the transformation potential of office buildings that are unoccupied or are likely to become unoccupied in the near future. We need to be able to measure this transformation potential both at location and at building level, and it will be convenient to be able to carry out both a quick, superficial appraisal (which we may call a ‘quick scan’) and a more thorough, detailed study (a ‘feasibility scan’). To this end, we have developed what we call a ‘transformation potential meter’ (Geraedts and Van der Voordt, 2000, 2003). The meter has been tested in practice by a number of market players, and has also been widely used by students of architecture who are nearing the end of their degree course. As befits good students, they have subjected the instrument to critical appraisal. This practical application has allowed the transformation potential meter to be evaluated and refined in 2006. Two new steps - the financial feasibility scan and the risk assessment checklist – have also been added to permit further investigation of the feasibility of a transformation project. In this paper, we describe the principle of the new transformation potential meter and its position in the Go/No Go decision-making process in the initial phase of a transformation project.

In Nederland staat bijna zes miljoen m2 kantoorruimte leeg. Dat is ca 15% van de
totale voorraad! Zelfs de meest optimistische vastgoedexperts geven toe dat voor
een deel hiervan ook bij een aantrekkende markt geen huurder meer te vinden zal
zijn. Slopen betekent vaak kapitaalvernietiging. Herbestemming naar andere
functies kan onder voorwaarden een goede optie zijn. De TU Delft doet onderzoek
naar kansen en risico's en ontwikkelt instrumenten voor verantwoorde
besluitvorming. Een beknopt overzicht.