Abstract: The instant invention is directed to an apparatus and methods for restraining a water heater to a supporting structure, such as a wall. The fastening system includes at least one bracket which mounts to the supporting structure and at least one restraining strap, one end of which attaches to a bracket, the other end of which can attach to another bracket, or mount directly to the wall, to hold the water heater tightly against the supporting structure. In some embodiments, the strap is long enough to encircle the water heater. In other embodiments, the strap can be split into two straps and joined at the water heater with tension buckles. In the preferred embodiment, two straps are used, and both are secured to the supporting structure with brackets. One of the straps encircles the water heater, and both connect to each other at the water heater through tension buckles.