Sustainable architecture : Green buildings What are they ? ENERGYENVIRONMENT Use renewable energy Prevent loss of energy Use less energy Minimize impact on environment Good use of the existing environment RESOURCES Avoid depletion* of resources Use recycled and sustainable materials *épuisement

Sustainable architecture : Green buildings (2) The main objectives of sustainable design are to avoid resource depletion of energy, water, and raw materials; prevent environmental degradation caused by facilities and infrastructure throughout their life cycle; and create built environments that are liveable, comfortable, safe and productive. As a result of the increased interest in green building concepts and practices, a number of organizations have developed standards, codes and rating systems that let government regulators, building professionals and consumers embrace green building with confidence. Green building rating systems such as BREEAM (United Kingdom), LEED (United States and Canada), and CASBEE (Japan) help consumers determine a structure’s level of environmental performance.

The seven steps for sustainable buildings

- proper site selection - location, orientation, and landscaping. - reduce, control, and/or treat storm water runoff. - reduce energy consumption (insulation / ventilation systems …) - increase efficiency, and utilize renewable energy resources - use water efficiently, and reuse or recycle water / collect rainwater - waste management (eg: compost / use of greywater for irrigation…) - use environmently preferable products - maximize daylighting - have appropriate ventilation and moisture control - maintenance: specify materials and systems that simplify and reduce maintenance requirements; require less water, energy, and toxic chemicals and cleaners to maintain Some rules for green buildings designers:

An example of sustainability in construction: Passive buildings The world’s first Passive House, Darmstadt- Kranichstein, Germany When was the first Passive House built? Who invented the Passive House?

Traditional building in Southern China. In this climate, cooling rather than heating, is required. Traditional passive houses Traditional turf houses in Iceland. Ingolstadt-Halmstadt: Low-energy houses (30 kWh/(m²a) heating demand) in two countries, by Architekt Hans Eek (1985)

Kronsberg Passivhaus Complex, Hannover, Germany The world's largest Passive House complex with 354 living units!

Different from low energy houses !

The term passive house (Passivhaus in German) refers to the rigorous, voluntary, Passivhaus standard for energy efficiency in a building, reducing its ecological footprint. It results in ultra-low energy buildings that require little energy for space heating or cooling. Although it is mostly applied to new buildings, it has also been used for refurbishments.energy efficiency buildingecological footprintultra-low energy buildings Estimates of the number of Passivhaus buildings around the world in late 2008 ranged from 15,000 to 20,000 structures. As of August 2010, there were approximately 25,000 such certified structures of all types in Europe, while in the United States there were only 13, with a few dozens more under construction The vast majority of passive structures have been built in German-speaking countries and Scandinavia.

Thermographic image illustrating difference in heat loss through building envelope in a conventional and passive house building. Source: UCD Energy Research Group.