In this section, the following terms have the meanings indicated. “Enclosed porch” means a porch that is enclosed by walls, screens, or other material on 2 or more sides. “Enclosed porch” includes a screened-in porch. “Unenclosed porch” means a porch that is open on 2 or more sides, even if the porch has a railing along the sides. Unenclosed porches may encroach 8 feet into any required front or corner-side yard. Unenclosed porches in the interior-side yard must be located at least 4 feet from the interior-side lot line. Enclosed porches must meet all minimum yard requirements. Front porches must remain open. Original porches must be retained and may not be filled in with opaque materials. For infill construction of 1 or 2 rowhouse units within a coordinated group of existing rowhouses, the following standards must be met:porch posts and railings must be compatible with the other houses in the row; steps must be oriented in the same manner as other houses in the row; and replacement steps must match the material of the steps original to the neighborhood. When replacing porch elements, the original elements of the row must be matched as closely as possible. T-1-11 paneling, plywood, vinyl and aluminum siding, and cinderblock are prohibited. Columns and railings are prohibited when not part of the original elements of the row. Foundations of ashlar stone must be repaired and repointed with matching mortar and mortar joints. Ord. 16-581