An exploratory study of the practice of stakeholder participation in densification projects

We report on the study of six similar buildings built in an area of Gothenburg, Sweden,
in 1971, which are now in urgent need of renovation. However, the owner of the
buildings - a municipal housing company did not achieve a financially viable
renovation of the pilot project. This meant that renovation on a similar basis for the
remaining five buildings would not be possible. For this reason the housing company
chose to undertake a vertical extension, by adding two floors with apartments on top
of the existing buildings. This has improved the economics and made renovation of
the five buildings possible. The objectives of this study are therefore, to show how a
vertical extension can make a renovation of these buildings financially viable. We
argue that a vertical extension can be applied to other similar buildings from this era.
If vertical extensions could make more renovations possible this would lead to a
significant impact on final energy use and carbon emissions. This case study has been
supported by a site visit, interviews with the housing company and the contractor,
document analysis, energy simulation and global warming potential simulation. Four
renovation concepts are compared in order to find the most appropriate: minimalist,
code-compliant, low-energy and low-energy plus vertical extension renovation. The
conclusion of this study is that vertical extensions provide enough incentive to preform
extensive energy renovations, which could reduce final energy use by more than 50%.