Decisions made early in the design process have a huge impact on how the house will perform over its lifetime – not only how much energy will be required to operate it, but also how comfortable it will be to live in. Keep in mind:
- Sustainable buildings encompasses design, building materials, and construction techniques. Success depends on the active participation of everyone who has a hand in the process.
- Solar orientation of the house has a powerful effect on comfort and energy use.
- Site conditions, such as natural vegetation, patterns of water runoff and seasonal water tables, and the direction of prevailing winds at different times of the year, have an important bearing on how the house should be sited and built.
- Room layouts that take into account how and when different rooms are used will be easier to heat and cool, and they’ll be more comfortable.
According to estimates from the U.S. Green Building Council and the Department of Energy, by the time 3% of the design budget for a new house has been spent, 70% of the energy use over its lifetime has been set in stone. So, what does that mean? It means that a tiny fraction of all design decisions- those made at the start of a project – largely determine how much energy will be required to operate the house.
Read more about planning your green remodel in Green from the Ground Up. The book begins with down-to-earth explanations of green building basics and move on to site planning, materials selection, energy efficiency, and indoor air quality — detailing along the way every step in design and construction, from framing to finishes.
Green Building Best Practices
Schedule a “design charette” before construction begins and include architect, builder, owner and all subcontractors.
Orient the house so that the south wall faces to within 30 degree of true (not magnetic) south.
In rooms on the south side of the house, windows should equal between 8% and 12% of the adjacent floor area. Proportions can be adjusted according to the relative mass of walls and floors that are directly and indirectly illuminated.
Shade windows on the south wall of the house from the summer sun, with either roof overhangs or awnings designed for the specific latitude where the house is being built.
Find out the direction of the prevailing winds (they may change seasonally), and specify casement windows on walls facing those directions. They do a better job of scooping up air for natural ventilation than do awning or double-hung windows.
Located rooms so they take advantage of natural light and heat at the time of day when they are more commonly used.
Control storm water runoff on site with perimeter drains, gutters, and subsurface drainage systems that accommodate anticipated groundwater levels and average rainfall (and snowfall).