Green homes can use recycled steel for their beams, and also for a reflective metal rooftop that is lightweight and durable. Green homes can use bales of straw for the walls, a building material that is perfectly natural, abundant and cheap.
|House with straw bale walls and a metal roof
Green homes can rest on a single finished concrete slab, efficently combining floor and foundation into one pour. The slab can be interlaced with tubes that channel solar heated water into the slab, warming it in winter.
In addition to providing solar-heated hot water and photovoltaic electricity, the entire roof can collect water from rain, filtering the runoff and storing it in cisterns.
There is an excellent television show called Building Green (http://www.buildinggreentv.com/) where the host introduces green building contractors and architects whose structures are as green as they come. A recent report on Building Green showed an entire roof covered in turf, with plants growing. What a fantastic way to filter rain, improve indoor energy efficiency, clean the air, and mitigate the urban heat island effect!
A goal of green buildings is to create a zero-impact building. A structure that has no net energy or water consumption, uses no toxic materials, and has no heat signature. According to statistics provided by the U.S. green building council (http://www.usgbc.org/), if the United States had 100% zero-impact buildings, they would save 40% of all national energy use, and 12% of all water use. Put another way, for every 10% gain in green building efficiency, the U.S. reduces energy consumption – from all sources – by 4%.
What is most interesting is perhaps the only remaining constraint on more green homes is the environmentalists themselves, whose activists have choked off suburban sprawl – translation: “affordable homes for you and me” – development on open land. Maybe now that the green home has arrived, environmentalists will step aside, and accept massive developments of low density green homes.