Strategies for energy efficient restorations

The conservation of our heritage buildings is a European wide policy objective. Historical buildings are not only works of art, but embody an important source of local identity and form a connection to our past. Protection agencies aim to preserve historical qualities for future generations. Their work is guided by restoration theory, a philosophy developed and codified in the course of the 19th and 20th century. European covenants, such as the Venice Charter, express shared views on the conservation and restoration of built heritage. Today, many users expect a building with modern comfort as well as a historical appearance. Moreover, new functionality is needed for building types that have outlived their original function. For example, how to reuse buildings such as old prisons, military barracks, factories, or railway stations? These new functions and new demands pose a challenge to restoration design and practices. Another, perhaps conflicting EU policy objective is the reduction of energy use in the built environment, in order to reach climate policy goals. Roughly 40% of the consumption of energy takes place in buildings, either in the production or consumption phase. However, energy efficiency is especially difficult to achieve in the case of historical buildings, because of strict regulations aimed at protecting historical values. Recently, there has been growing interest in energy efficient restoration practices in the Netherlands, as is shown by the 'energy-neutral' restoration of Villa Diederichs in Utrecht, the 'Boostencomplex' in Maastricht and De Tempel in The Hague. Although restoration of listed buildings is obviously focused on the preservation of historical values, with the pressing demands from EU climate policy the energy efficiency of historical building