New homes are up to six times more energy-efficient than those built in 1900.
This is set to increase even more within 10 years as the government has proposed that all new-builds should be carbon neutral by 2016.
Being carbon neutral means that the proprty produces as much energy as they consume.
Many new house builders have already started to prove their eco-credentiais by designing eco-friendly homes. Some of the features they include over and above being every energy efficient are inclusion of water butts to collect rainwater, recycling facilities and a drainage system which helps reduce the amount of pollutants being washed into rivers.
Want more information? These books about green buildings may be of interest