Abstract
<jats:p>To solve the housing shortage, some 90,000 new homes must be added to the housing stock each year. Transforming vacant buildings and repurposing them into housing will help solve this. Until around 2014, transformation was seen as a solution to the vacancy rate in the office market, which rose high during the period 2001-2013, nationwide from around 5% in 2001 to almost 15% in 2013. The high vacancy rate was partly the result of the dotcom crisis and the financial crisis, which together with technological developments and an increase in flex-working led to fewer square meters of offices needed, while a surplus of offices was being developed and built. Around 2014, a tipping point became visible. Transformation was increasingly motivated by the demand side of the housing market and no longer by the supply side of the office market. The focus on sustainable building and making the existing building stock more sustainable increased. In the 2007 book Transformation of Office Buildings, sustainability was barely mentioned. At most, transformation was mentioned as intrinsically sustainable because the building was reused. However, due to increased energy costs and costs of building materials, as well as the climate crisis, sustainability aspects such as energy-efficient, circular and adaptable construction have become much more important, although they are not yet universally applied. The Netherlands has a high demand for housing, but in addition many buildings are empty. In many places in the Randstad there are obsolete office buildings that are no longer in demand. Across the country, churches are becoming vacant due to an aging population and secularization. Industrial real estate is losing its function as industry moves out of the inner cities to more accessible locations or abroad. School buildings are becoming vacant because of aging neighborhoods. Hospitals are becoming vacant due to the introduction of new care concepts and economies of scale. Many stores are becoming vacant due to centralization and online shopping. Buildings originally built for these (and other) functions can be transformed into housing. Fusing old and new helps preserve identity. When architecturally interesting buildings are also involved, transformation contributes to the preservation of cultural heritage. Transformation can contribute to making the building stock more sustainable and reducing resource use and demolition waste. Transformation could contribute 10-15% of housing production annually. The conclusion seems logical: transform vacant buildings into housing. But it's not that simple. Vacant property owners and housing developers do not always know how to find each other. Transformation is different from new construction and requires a different approach. There are also all kinds of financial-economic, legal and policy challenges, such as uncertainty about financial feasibility and fear of lengthy procedures. That is why we have taken the initiative to publish this book precisely now, at a time when we are in the midst of both a housing crisis and a climate crisis. With this book we want to give more insight into the opportunities and challenges of transformation. We feature actors who have gained experience from different perspectives, and we discuss projects that show the breadth of Dutch transformation practice. This book was written by researchers at TU Delft, but we also approached several practitioner experts to contribute. This has produced a wide range of themes. Transformation is highlighted from different perspectives with a focus on feasibility. We then discuss transformation as a sustainable design, development and management strategy. The role of different actors is discussed in the perspectives section: owners, investors, developers, corporations, architects, users and governments. Finally, we present a number of transformation projects.</jats:p>