2. Application examples

The eco-design approach has been applied to a variety of projects, both in new construction and renovation, in the residential sector as well as in the service sector (offices, school buildings, etc.). These applications have demonstrated the importance of the use phase: in today's standard house, for example, the construction phase accounts for only around 20% of energy consumption, compared with 80% for use (heating, domestic hot water, lighting and other uses of electricity). But for a house that complies with current best practice in terms of energy efficiency (German "Passive House" label), the share for construction can rise to as much as 50%. Compared to a standard gas-heated house, a passive house heated by a heat pump emits 3.5 times less CO ₂ but generates 30% more radioactive waste