Green home building is a real field with real benefits to home buyers. It encompasses everything from selecting the right site for the home on the lot, to making best use of the tress and any landscaping that are already in place; reducing construction waste, recycling, and using recycled materials when appropriate; and energy-efficient design of the home. Materials like low-E insulated windows; wall, attic, and basement insulation; Tyvek wrap and elastomer sealants on exterior walls; energy efficient HVAC, water heater, and appliances; water-saving showers, toilets, and landscape irrigation; and a lighting system optimized to make best use of natural light all contribute toward a home that maintains a healthy and comfortable environment while reducing environmental impact and the costs associated with running the home.