THE ENERGY FUTURE OF EXISTING BUILDINGS IN BRUSSELS: BETWEEN PRESERVATION AND PERFORMANCE

is the unbroken continuity in the craft between manufacture, the construction of the component and its repair. Within the context of the diagnostic approach to Brussels houses that should precede any work on a building, it is interesting to examine the energy renovation campaigns carried out in the 1970s and 1980s (fig. 6 and 7). Today, exterior joinery installed thirty or forty years ago is being replaced, whereas if the maintenance cycles had been continued the original elements could have been preserved. The issue of construction waste is also important as it makes up a large part of the total volume of waste generated in the Brussels Region. Building tradesmen help to limit the volume they produce by mastering repair and maintenance techniques that enable the existing components in the building to be maintained.

ENERGY RENOVATION AND HERITAGE: SOME EXAMPLES OF WORK

The example of the building located on Rue du Rouleau (in the Béguinage quarter, central Brussels) is interesting as it was the subject of a low energy renovation in the early 2000s (fig. 8 and 9). It was therefore, in defence of the person behind the project, one of the first energy renovations of this type in the city. The interior of the building was completely gutted leaving only the exterior walls remaining. This is therefore an example of façadism, justified by the energy renovation. In effect, the fact that only the exterior walls were retained ensured the continuity of the interior insulation without creating thermal bridges in front of the floors. An operation of this type does not leave much in the way of the original building materials remaining and generates huge amounts of construction waste.

The “menu” for a low energy renovation almost always includes two interventions that have a potentially significant technical and aesthetic impact. The first concerns the building envelope, which has to be heavily thermally insulated as well as airtight. The second involves installing double-flow ventilation with recovery of heat in interior spaces that were not designed for it. Figure 10 illustrates a low energy project in which the interior insulation of the façades faces a very practical problem: the join between the insulation and the ceiling. In this case, solutions must therefore be found in order to reproduce the mouldings. The same problem arises when integrating the double-flow ventilation.

Fig. 8 and 9

Low energy renovation, Rue du Rouleau, Brussels. Overview (left) and close-up of interior wall insulation (right) (photos by author).

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