An international team of experts is working on an EU-funded project that hopes to make historic buildings more energy efficient by reducing the amount of energy that is lost through windows.

While we often seek ways to make our homes and public buildings more energy efficient, it is less often we spare a thought for the energy lost at badly insulted historical sites. The project 3ENCULT ('Efficient energy for EU cultural heritage') wants to change all that.

3ENCULT, which received almost EUR 5 million of funding from the 'Environment' Theme of the EU's Seventh Framework Programme (FP7), brings together researchers from Belgium, the Czech Republic, Denmark, Germany, Spain, France, Italy, the Netherlands, Austria and the United Kingdom.

The first stage of the project has involved upgrading the windows of the Waaghaus (Public Weighing House), a building located in Bolzano, Italy, that is over seven centuries old.

Many windows in ancient buildings have been badly renovated, and as a result are neither aesthetically nor historically accurate. For this project, the building's curator, Waltraud Kofler-Engl, and the expert window designer, Franz Freundorfer, were given free rein to come up with a new energy-efficient window design that integrated well into the building's existing façade. The resulting design is called the SmartWin Historic Window, and the first prototype was installed in the Waaghaus building in February 2012.

Alexandra Troi, vice-head of the Institute for Renewable Energy at the European Academy of Bozen/Bolzano (EURAC) and scientific coordinator of 3ENCULT, overlooked the development of the new window: 'With our window, we believe we have a solution for all historic buildings. The SmartWin Historic Window is not only a very good insulated window that fits perfectly in historic buildings; it's also affordable.'

Alexandra Troi continues: 'We will now measure and analyse different parameters of this prototype and compare it to one of the old windows from the 1950s. Having a prototype installed now, which can be touched and examined, is a good starting point for multidisciplinary discussions.'

The 3ENCULT project runs until 2012; now the team will continue to refine the next prototype, which must meet criteria of feasibility and cost-efficiency.

From an aesthetic point of view, curator Mrs Kofler-Engl comments on what can be done to improve on this first prototype: 'The narrow frame and the two [sash bars] of the double-winged window look very good. But in my opinion the triple glazing doesn't fit the look of the building. And I think the antique styling of the glass used for the outer windowpane is a bit exaggerated. Perhaps a double glazing inside and a simple, single glass layer on the outside might be enough.' Source: European Union