Sustainability in architecture is all about:

 

healthy buildings which are free from toxic emissions

airtight buildings which keep unwanted draughts out

superinsulation which keeps the building warm

breathable construction using natural materials which allows moisture to pass through the building fabric

solar shading using louvres and plants to reduce summer overheating

minimising water use by fitting low water demand appliances and taps

sourcing materials locally wherever possible

natural and renewable energy like wood for heating, and wind and sun for electricity generation

rainwater capture for use in the building (washing machines and wcs) and to irrigate gardens

reed beds to treat sewage on site

re-using buildings wherever possible to avoid waste

designing buildings so that they are easy to deconstruct using minimal energy and creating as little waste as possible