The Dept of Energy passed a rule on the efficiency factor (EF) of all water heaters manufactured after 4/15/15. The bottom line is it's about to get a whole lot more expensive to buy a new water heater in the USA so if yours is pretty old it may be a good idea to replace it while you can still buy the old style water heaters. 40-50 gallon models (the most common size) are going to be costing 15-20% more than the units that are still available. If you have a larger water heater get ready for a huge increase in what it typically costs to replace it. Larger heaters, bigger changes There are many factors for home builders and remodelers to consider when deciding whether to specify these new larger water heaters. First is the cost: Conventional, current minimum-efficiency 60-gallon gas and electric water heaters are approximately $675-$1,500, while the new high-efficiency models are about $1,200-$2,450 http://www.nahb.org/generic.aspx?genericContentID=236255 This PSA has been brought to you by me, and as my old pal LonghornJ used to say, "act accordingly".