A nonconforming structure or use may not be changed, altered, replaced, added to or expanded in any manner unless such change or alteration would bring the use into conformity with the uses permitted in the district in which it is located. Such limitations and restrictions shall not apply to existing residential dwellings, and commercial nonconforming uses which would qualify for a one-time expansion up to 10% of existing building area. Nonconforming residential structures shall not be remodeled or expanded in a manner that increases non-conformity.

In case of partial or complete destruction by fire or other causes requiring expenditures for repair in excess of one-half the assessed value as shown on the county assessor's records immediately prior to destruction, the structures, other than residential dwellings, shall not be rebuilt unless they conform to all requirements of the district in which they are located.

If a nonconforming use is discontinued for any reason for more than three years, it shall not be reestablished.

Any nonconforming structure or use may be maintained with ordinary care.