Demolition shall be defined as the dismantling, tearing down, removal or razing of the exterior of a building, in whole or in part. This term shall not include changes to the interior of a building, provided such changes do not alter the structural integrity of the building. A partial demolition shall mean: 1) removal of exterior portions of a building, or 2) removal of original exterior architectural features, such as, but not limited to, an attached porch roof, porch columns, cornices, exterior window details or similar features.