My company performs home inspections in San Diego. There are programs that evaluate homes and give them rating as to how efficient they are, or what products were used in the construction of the house. "Green" has taken on several meanings. Does it mean having high-efficiency equipment and appliances to use less energy? Does it have solar panels? A gray water system? Or does it mean that the house used only sustainable products such as natural wood molding, low VOC carpet and paint, natural wood flooring, arid climate garden, etc.
There are some important things to keep in mind when looking at houses, because there is such a difference between a house from the 1950's, or one that has been recently built. Newer houses must meet strict building codes which demand higher levels of insulation, higher efficiency heating and cooling equipment, double pane windows, low flow plumbing fixtures, etc. But they also use many engineered products such as particle board (cabinets, molding, flooring), plastics and solvents, chip board sheathing and so on. There are two schools of thought on these engineered products. One thought is that by using scraps of wood to make products such as particle board and molding, there is less waste, and less demand for trees. The other school of thought is that engineered products use lots of glues and chemicals in the manufacturing process.
To some people, buying a nice old home from the 1950's is great because they used more natural materials (solid wood instead of engineered), you don't use up new products, and the houses are typically smaller and don't require as much energy demand (due to minimal appliances, AC) as a big new house. Other people believe that a brand new house is more efficient (true) but they use a lot more resources in their construction (also true). But new houses use less energy over the long haul (also true).
So, YOU need to define what "Green" means to you. If you are looking at a particular house and want to have it evaluated for efficiency, let us know.
The San Diego Real Estate Inspection Co.... more