I am in Oklahoma and had a gas hot water heater in my old garage and stored two different boats in the garage actually on the same side as the hot water heater. As long as your hot water heater is elevated which most newer installs are, and your boat isnt leaking or you can smell gas fumes you are probably ok – BUT definitely do take every precaution. I just thought Id relay my experience to you.Jason Ferbrache – Edmond, OK 1995 Basscat Eyra