Water heaters should be elevated to 1’ above base flood elevation (BFE) in keeping with habitable spaces of newly-constructed homes. Many raised areas like stands, cantilevered specialty platforms, and custom decks can serve this purpose.
Because the horizontal forces of an earthquake have a tendency to push over water heaters, they should be securely fixed to a structure. Strapping will also serve as restraint against wind when water heaters are housed on stoops or balconies outside the house. Bracing is required for new water heater installations and is recommended as a top priority for existing installations. Kits for bracing water heaters are available at many hardware stores. As an alternative to kits, anchorage can be achieved by using steel strapping fastened to perpendicular walls. Be sure to maintain required service and operation clearances. In addition, making the service connection to the water heater with a flexible connection that is not taut (i.e., with some slack) is recommended.
Some jurisdictions place additional limits on water heater bracing details. Where water heaters are installed on a platform, the water heater base should be attached to the platform and the platform should be anchored to the floor. Placing water heaters in metal pans to retain any spilled water is a possible precaution in addition to bracing.