No, but they don’t hurt.
Building products made from recycled products don’t make a house green by themselves any more than solar or photovoltaic panels do. But keeping the goals of sustainable building in mind can guide purchasing decisions in the right direction.
Take something innocuous, like a stone countertop or a bamboo floor for a kitchen . Stone and bamboo are natural materials that off-gas no hazardous chemicals and are extremely durable—all positives. But what if they are imported from the Far East or mined in a country where labor or environmental laws are suspect? Is the material still green? Well, not as much. It would be better to purchase flooring and stone locally, even if that limits the number of options.
The same template can be applied to purchases of wood products. Illegal logging is rampant in some parts of the world, threatening regional ecologies and in some cases underwriting violent criminals. Buying lumber that has been harvested locally or certified as sustainable by a third-party, such as the Forest Stewardship Council, is a contribution toward green building.
But choosing appropriate materials is a lost effort if the house itself wastes fuel or is poorly designed and haphazardly built. Green products are becoming more plentiful all the time, and given the right context they are an important part of sustainability. It’s the context part we shouldn’t forget about.
Original article can be seen here http://www.greenbuildingadvisor.com/content/if-i-use-only-green-or-recycled-building-products-my-house-green