Kan. Stat. § 19-2908
Regulations adopted under authority of this act shall not apply to existing structures nor to the existing use of any buildings or land, but shall apply to any alteration of a building to provide for its use for a purpose or in a manner different from the use to which it was put before the alteration. This act shall not prevent the restoration of a building damaged not more than fifty percent of its assessed valuation by fire, explosion, act of God, or the public enemy, or prevent the continuance of the use of such building or part thereof as such use existed at the time of such damage, or prevent a change of such existing use except under limitations provided herein in relation to existing buildings and premises. Except for flood plain regulations in areas designated as a flood plain, regulations adopted pursuant to this act shall not apply to the use of land for agricultural purposes, nor for the erection or maintenance of buildings thereon for such purposes so long as such land and buildings erected thereon are used for agricultural purposes and not otherwise. No plat nor dedication of any such land for public purposes may be made without submission to the zoning board and the approval of the county commissioners.
K.S.A. 19-2908