G109 Manufactured Homes — 2025 California Building Code

All new and replacement manufactured homes to be placed or substantially improved in a flood hazard area shall be elevated such that the top of the foundation for the manufactured home is at or above the design flood elevation.

All new and replacement manufactured homes, including substantial improvement of existing manufactured homes, shall be placed on a permanent, reinforced foundation that is designed in accordance with Section R306 of the California Residential Code .

All new and replacement manufactured homes to be placed or substantially improved in a flood hazard area shall be installed using methods and practices that minimize flood damage. Manufactured homes shall be securely anchored to an adequately anchored foundation system to resist flotation, collapse and lateral movement. Methods of anchoring are authorized to include, but are not limited to, use of over-the-top or frame ties to ground anchors. This requirement is in addition to applicable state and local anchoring requirements for resisting wind forces.

Mechanical equipment and outside appliances shall be elevated to or above the design flood elevation.

Exception: Where such equipment and appliances are designed and installed to prevent water from entering or accumulating within their components and the systems are constructed to resist hydrostatic and hydrodynamic loads and stresses, including the effects of buoyancy, during the occurrence of flooding up to the elevation required by Section R306 of the California Residen- tial Code, the systems and equipment shall be permitted to be located below the elevation required by Section R306 of the California Residential Code . Electrical wiring systems shall be permitted below the design flood elevation provided that they conform to the provisions of the California Electrical Code.

Fully enclosed areas below elevated manufactured homes shall comply with the requirements of Section R306 of the California Residential Code .