The Residential 2 Subdistrict is established to preserve existing residential structures, to provide for new infill construction appropriate to the existing fabric and density, and to allow additions and updates, including Accessory Dwelling Units (ADUs). In a Residential 2 Subdistrict, the maximum number of Dwelling Units allowed on a single lot is 3, exclusive of any ADU; the maximum number of Dwelling Units including Accessory Dwelling Units is 4.