Chris writes from Oviedo, Florida: "We have added another bedroom and a garage to our house. My father is the contractor and suggested we put in a second water heater for that side of the house. It sounds like the costs would outweigh the benefits. What do you think?"

Answer: Owens Corning makes insulating materials and your question is outside our area of expertise. Your question should be addressed to a plumber or water heater manufacturer. Other options include checking with the Gas Appliance Manufacturers Association (GAMA), or an organization with information about electric water heaters, such as Madison Gas and Electric. Finally, you might check into demand (tankless or instantaneous) water heaters. Tankless water heaters provide hot water only as it is needed. They don't produce the standby energy losses associated with storage water heaters, which can save you money. For information about that option, check the Consumer's Guide section of the U.S. Department of Energy Web site.