Agricultural Structures Building Act of 2013 - Amends the National Flood Insurance Act of 1968 to allow local variances for certain agricultural structures (such as any agricultural product processing facility, agricultural product storage facility, shed, farmhouse, barn, or other structure which has as its primary purpose supporting the agricultural industry).
Prohibits certain land use and control measures from being deemed inadequate or inconsistent with land management criteria for participation in the flood insurance program because such measures authorize granting a variance for an agricultural structure located in an area having special flood hazards.
Prohibits the Administrator of the Federal Emergency Management Agency (FEMA) from either suspending a community from participation in the national flood insurance program, or placing it on probation, because its land use and control measures provide for such a variance.
Defines such variance as one granted by an appropriate official of the community from compliance with such land use and control measures and permits repair and restoration of such structure to its pre-damaged condition without elevation of the structure.
Requires the official to have made specified determinations as a prerequisite to granting such a variance, including that: (1) in the case of new construction, the agricultural structure is subject to base flood elevations of at least three feet; and (2) in the case of existing structures, it is not practicable to elevate the repaired or expanded structure to the base flood elevation.
Requires the chargeable flood insurance premium rates for an agricultural structure granted such a variance to be the rates that otherwise would apply to such structure if it had been repaired, expanded, or constructed before the establishment of the special flood hazard area.