We recently had to replace our water heater for our home. While the plumber was here, I asked him about the effectiveness of a water heater blanket. He said that water heaters are designed with internal insulation, so unless you have a very old water heater, it is a waste of money. They cost anywhere from $20-$50.
He said to touch the drum. If it feels very hot to the touch, you may have an old unit and may need to cover it with a water heater blanket.
Water heater blankets are available for both gas and electric water heaters. However, he cautioned ever putting one on a gas water heater.
