Any nonconforming building or structure which is accidentally damaged or destroyed, or is in a dilapidated condition, may be restored or rebuilt to be used as before, provided that the restoration or rebuilding does not make the building or structure more nonconforming than previously as to its height or setback from property lines, and provided, further, that the restoration or rebuilding is completed within one year of the date the damage or destruction occurred or the date of insurance settlement, unless the Planning Commission recommends and the Board of Supervisors grants an additional year to complete the work because a hardship is created for the owner by the one-year limit.