Policy Instruments: The Case of Germany - Nearly Zero Energy Building Refurbishment - page 29

Fig. 5 The long-term impact of different renovation tracks

potential in the building stock and thus achieve the targets. The road map should
also help to give an orientation for the future development of the building stock
and to identify a suitable path towards a climate-neutral building stock by 2050.
Figure 5 qualitatively shows the importance of choosing the right refurbishment
track.
Accordingly, a refurbishment track with a very high speed but just an average
ambition level can lead to fast reductions; however, due to the long renovation
cycles of buildings, it can also lead to a lock-in effect which in the long term leads
to a non-achievement of the reduction targets.

3.2 Regulatory Policies

In Germany, the requirements concerning the energy performance of buildings
reach back a long time (first Thermal Insulation Ordinance since 1977) and the
requirements have been continuously tightened. The specifications of the 'Energy
Performance of Buildings Directive' (EPBD) are transposed through the 'Energy
Saving Ordinance' (EnEV) in Germany. According to the EnEV, new residential
and commercial buildings have to limit their primary energy demand to a specified
maximum value. Minimum requirements also exist on component level and for the
specific transmission heat loss, which is calculated by using reference buildings.
For existing buildings, there are also minimum requirements for building com-
ponents in the case of a building modification and for the primary energy demand
in the case of a major renovation that is 40 % less ambitious than those for new
buildings. The calculation of the overall primary energy demand has to be