We are renovating our home and our builder suggested a second electric water heater as a supplement to our gas water heater. He then installed them such that the cold water enters the electric heater first and then the electric-heater water goes to the gas water heater for storage. This strikes me as backwards. It seems to me that the cold water should be heated by the gas water heater and then "stored" in the electric heater, which would only come on to maintain the hot temperature, rather than heating the water itself.

Thoughts on this?