A case study of a Norwegian detached house is used to evaluate the sustainability of two nearly zero energy renovation strategies. Energy demand, life cycle cost and home qualities are assessed as sustainability indicators. The Façade renovation strategy is an energy upgrade of the façade supplemented with high renewable energy production on site. The Ambitious renovation strategy is a total building envelope upgrade using passive house components and a lower on site renewable energy production. Both renovation strategies result in a 50–85% reduction of the heating requirement depending on the renewable energy production. The sustainability assessment was done as an iterative process including qualitative and quantitative parameters. The Ambitious renovation strategy is more costly than the Façade alternative over a 30 year period. However, homeowners do not base their decisions to renovate strictly on cost evaluations and homeowner categories influence the assessment. The Façade strategy is suitable for homeowners that do the retrofit themselves and homeowners prioritizing to keep the existing architectural qualities of their house. The Ambitious strategy is more suitable for the homeowners seeking to change the aesthetics of their home as well as for the homeowners emphasizing the overall technical performance after renovation.
The building skin is often called the third skin of a human being after the body skin and clothes since it provides protection from the elements, creates privacy and provides contact between the indoor and outdoor space. Moreover, it is the most important element regarding the total energy balance of buildings. Solar energy systems, and in particular solar cells, have an important role to play in reducing energy needs of buildings. Several building surfaces are ideally suited for the use of solar panels, but high costs as well as technical and aesthetical considerations have long kept building owners and architects from using even a small part of this potential. The paper is the result of a study that investigates the architectural potential of existing photovoltaic materials and product development trends. The main goal is to give an overview of current possibilities and discuss their relevance for future development regarding architectural integration.
Zero emission buildings (ZEB) are buildings with a minimized energy consumption and renewable energy supply with zero greenhouse gas emissions. There is no common accepted definition of zero emission buildings. This is due to issues in defining the boundary of a balance in terms of building site and time frame of this balance. Further, there is no standard on accounting for emissions (on material, components, system, and building level) nor is there a standard for emissions from other building related environments. In this paper the goals for ZEB are specified and implications for components are discussed.