Small might be beautiful, but bigger performs better: Scale economies in “green” refurbishments of apartment housing

- First study to analyze the effects of housing companies size on “green” refurbishment
- Economies of scale, scope and learning all affect energy efficiency refurbishments.
- Specialization on distinct refurbishments influences outcome of thermal upgrades.
- Analysis based on a large and unique sample of apartment buildings in Germany

The energy efficiency of the residential housing stock plays a key role in strategies to mitigate climate change and global warming. In this context, it is frequently argued that private investment and the quality of thermal upgrades are too low in the light of the challenges faced and the potential energy cost savings. While many authors address the potential barriers for investors to increase energy efficiency, studies on the capabilities of different investors to reduce energy requirements of their property are scarce. This study investigates potential advantages of housing company's size, i.e. economies of scale, economies of scope and institutional learning in thermal upgrades of residential housing. Based on unique data on energy consumption in 102,307 apartment buildings in Germany, we present new evidence for the advantages and disadvantages of a housing company's size in “green” retrofitting projects. Our estimations show, that large housing companies outperform private landlords by far in high effort refurbishment projects. In contrast, private landlords appear to have advantages in low effort, incremental refurbishment activities. We demonstrate that a substantial share of the advantages of larger firms can be associated with specialization (i.e. repeated projects). The results offer new options for policy makers to refine the support schemes toward a low carbon housing stock.