Stains have become a major home performance issue. Here are more techniques to help find the causes of stains--lab sampling, examination under a microscope, and a close look at particle colors.

After years of talk about energy efficiency and green building, there is a still a communication gap between green building advocates and mainstream developers. Bridging this gap takes nothing but basic communication--but that can be harder than it sounds.

Shopping for energy design software can be intimidating. Power user Bion Howard cuts through the jargon and explains how to make a choice.

Labeling windows for energy efficiency takes more than a stack of stickers. It takes years of behind-the-scenes calculations--and resolving conflicts--to develop a label. The world's three different window labeling systems have taken different approaches, each with its own lessons.