Many common household products, including paints, wood stains, glues, carpets, and...

An invisible threat in many homes, this colorless, odorless, radioactive gas, radon is produced naturally in the soil from the decay of uranium. If it enters buildings (via holes in the foundation, cracks in walls, and the like; it can also enter via well water), it can become trapped and accumulate, creating a serious health hazard. Radon is the second biggest cause of lung cancer, after smoking. The Environmental Protection Agency (EPA) estimates that one in 15 U.S. homes has a radon problem to some degree, and recommends that all homeowners have their homes tested (either by a professional or with a do-it-yourself kit. (Test kits are available at home-improvement stores and from the National Safety Council.) If elevated radon levels are found, there are steps you can take to lower them: Having a fan and vent system installed, to vent the radon from beneath the house to the outside, is one approach.

Seeing pages and pages of glossy magazine photos of sustainable homes replete with glass panels...