The BK-city heat hole

Thermograms by Michael Prodromou

Not only the exterior of BK-city is monumental, so too is its heat loss, says Michaelis Prodromou (MSc), whose graduation project focused on BK-city’s sustainable refurbishment.

Last week Michaelis Prodromou was one of the three laureates for the UfD-Cofely Energy Efficiency Awards. He originally came to Delft to pursue his Master’s degree in Building Engineering (Civil Engineering and Geosciences) because of the programme’s environmental aspects. “The Netherlands is a front runner in climate change studies, together with Germany, Denmark and Sweden,” Prodromou says on the telephone from Athens. He now works for the World Wildlife Fund developing an energy efficiency label for apartments.

BK-city is a colossal building on the northern edge of the campus that has served during its long history as a uranium depot and refugee shelter, as well as the TU’s (former) Main Administration office. It was built in the 1920s and is now – as Prodromou puts it – characterised by “its obsolete fabric and outdated building service systems.” Prodromou vividly recalls his first visit to the Architecture faculty, which now houses BK-city. “On the second floor Bachelor’s students were dripping sweat over their drawings while one floor below
people were wearing coats behind their desks.” He was immediately motivated to come up with plans that would both respect the building’s monumental exterior yet at the same time improve the internal climate and energy efficiency. “It can turn into a monument for good environmental practice,” Prodromou says. It should be noted here that poor as its energy efficiency may be, BK-city is not an exception among Dutch educational buildings.

The largest heat leaks are via the large, high windows. But because of their aesthetics they cannot easily be replaced by well-insulated double-glazing. Nor can their steel frames support double-glazed windows. Prodromou therefore proposes to place extra windows behind (on the interior side of) the original ones. In the few places where this not feasible, he proposes to uses thick curtains to provide extra insulation. Apparently similar windows with good thermal properties can be manufactured, but the costs seem to be prohibitive.
The other large thermal leak is the roof of the building, which carries no insulation whatever.

“Simple measures can bring enormous improvements,” says Prodromou. In his thesis he presents three refurbishments strategies named ‘basic but cheap’, ‘ambitious but feasible’ and ‘innovative but risky’. Even the basic renovation plan entails a drastic insulation of walls, floors and attic, reducing draft and improving ventilation.

More advanced ideas feature a heat storage tank in BK-city’s large but inaccessible tower (originally designed as a tank for storing fire-extinguishing water), shading the windows and geothermal heating. Calculations show that energy use can be reduced by between 25 to 70 percent.
Prodromou’s thesis supervisor, Professor Andy van den Dobbelsteen, is working with Professor Wytze Patijn on a follow-up report. Both professors are presently unavailable due to skiing holidays.

Link to thesis in repository:
http://bit.ly/hIuMbY