Recycling paper and plastic is standard in most American cities, but now more people are turning to recycled building materials for construction projects. These bricks from a 100-year-old South Bend, Indiana, building were used to build a new home. Builders are looking at ways to reduce their excessive carbon footprint. The Home Builders Association of Northern California recently pledged to slash carbon dioxide emissions in half by 2020, using green technologies. The USGBC says the building sector accounts for nearly half annual domestic and global greenhouse gas emissions. (© AP Images)