The DC historic preservation law defines demolition to mean the razing or destruction of a historic building or structure “entirely or in significant part.” That standard is further defined in the Historic Preservation Review Board’s rules of procedure to include any of the following:

• The removal or destruction of any façade

• The removal or destruction of all or a substantial portion of the structural components of the building, such as structural walls, floor assemblies, and roofs

• The removal or destruction of all or a substantial portion of the roof along with all or substantially all of one or more exterior wall

• The removal or destruction of all or substantially all of an entire wing or appendage of the building, such as a rear ell, unless the wing lacks physical or historic integrity, or is not a character-defining feature

• The removal or destruction of a substantial portion that includes character-defining features of the building or structure

• The removal or destruction of all or a substantial portion of a designated interior landmark, unless the elements to be removed lack physical or historic integrity, or are not character-defining features

• Any removal or destruction requiring a partial demolition or raze permit under the D.C. Construction Code, including any demolition of non-bearing walls, interior finishes, or other interior non-bearing elements within a building where an interior space has been designated as a historic landmark