The lawful nonconforming use of a structure, land or water existing at the time of the adoption or amendment of this chapter may be continued although the use does not conform with the provisions of this chapter. However, only that portion of the land or water in actual use may be so continued and the structure may not be extended, enlarged, reconstructed, substituted, moved or structurally altered, except when required to do so by law or order so as to comply with the provisions of this chapter.

Total lifetime structural repairs or alterations shall not exceed 50% of the current assessed value of the structure unless it is permanently changed to conform to the use provisions of this chapter.

Changes of use may be permitted by the Board of Appeals if such changes will reduce the incompatibility of the nonconforming use with the neighboring uses.

A lawful nonconforming structure existing at the time of the adoption or amendment of this chapter may be continued although its size or location does not conform with the lot width, lot area, yard, height, parking and loading, and access provisions of this chapter.

A lawful nonconforming structure may be maintained, repaired, remodeled, enlarged or structurally altered so long as the nonconformity is not extended, enlarged or in any way made more nonconforming to the requirements of this chapter. Except as expressly authorized in the preceding sentence, a lawful nonconforming structure shall not be extended, enlarged, reconstructed, moved or structurally altered, except when required to do so by law or order.

A lawful nonconforming structure damaged or destroyed by violent wind, vandalism, fire, flood, ice, snow, mold, or infestation may be restored or reconstructed pursuant to the regulations set forth in § 62.23(7)(hc), Wis. Stats.