Many of the office designs that have ‘green’ accreditation in New Zealand were substantially designed before the rating system was introduced. The fundamental characteristics of the building envelope are likely to have been decided before any ‘green’ analysis could be applied. Many of these designs have subsequently been able to achieve a ‘green’ rating with little compromise to their appearance. Having said that, they have worked within the constraints of the rating system and adhered to its requirements. However, while the total energy consumption of these buildings is small compared with the whole building stock, their impact has been disproportionately large due to media coverage.
If the combined effects of climate change and fuel depletion result in reduced and insecure electricity supplies, then highly glazed, sealed and air-conditioned buildings could frequently become uninhabitable and unproductive. Real estate’s Grade A office space will become undesirable and the naturally ventilated and daylit buildings with appropriate shading will be shown to be sustainable. It is the characteristics of these building types that should be promoted further in ‘green’ rating systems.
Changing a few of the criteria for ‘green’ rating could marginally shift the rating tool towards encouraging an improved performance of the building envelope. Ultimately an insecure supply of electricity will fundamentally alter the weighting for ‘energy’ within a rating tool and the idea that a building, which is completely dependent on electricity in order to remain habitable, could be considered sustainable is in need of review.