(A) Intent. The design standards in this section outline required building details for alterations, additions and new construction, which serve to reinforce the traditional development character of the Historic Zoning Districts.
(B) Roof type requirements.
(1) Pitched, hipped, gabled, or a combination are also permitted within the Historic Zoning Districts subject to conformance with the Historic Design Guidelines and subject to approval of the ARB.
(2) Flat roofs.
(a) Flat roofs are permitted within Historic Dublin, except for properties that are zoned Historic Core, unless otherwise determined by the ARB to be architecturally appropriate.
(b) Eaves are encouraged on street-facing facades.
(c) Flat roofs are permitted to use a roof material appropriate to maintain proper drainage.
(3) Parapets.
(a) Parapets shall be provided on flat roofs that are high enough to screen the roof and any roof appurtenances from view from the street(s) and any adjacent building of similar height or lower, provided that parapets shall be no less than two feet and no more than six feet high. Where a six-foot parapet is insufficient to screen rooftop mechanical equipment a screening structure shall be required.
(b) Parapets shall wrap around all sides of the building.
(4) Pitched roofs.
(a) Hipped and gabled roofs are permitted, in addition to roofs with combinations of hips and gables with or without dormers.
(b) Permitted pitch roof materials include dimensional asphalt composite shingles with a 25-year or greater warranty, wood shingles and shakes, metal tiles or standing seam, slate, and ceramic tile. Other high quality simulated examples of these materials may be approved by the ARB with examples of successful, high quality installations in comparable climates.
(c) Pitch measure.
1. The principal roof shall have a pitch appropriate to the architectural style of the building. Roofs shall not be sloped less than a 6:12 (rise: run) or more than 12:12, unless otherwise determined to be architecturally appropriate by the ARB.
2. Slopes greater than 12:12 may be used on pitched roofs without a closed ridge to accommodate mechanical equipment within the roof structure and screened from view. These roofs must be designed with the appearance of closed ridges when viewed from all directions at street level and, to the maximum extent practicable, from buildings of similar heights in close proximity. The use of this roof configuration and pitch shall be based on the appropriateness of the roof design to the architectural style.
3. Unless determined to be appropriate to the architectural style of the building, a pitch greater than 3:12 is required on roofs of dormers, porches, balconies, or other minor roofs.
(5) Gambrel and mansard roofs.
(a) Gambrel and mansard roofs are permitted only for single-family detached buildings, unless otherwise determined by the ARB to be architecturally appropriate for other uses.
(b) Gambrel and mansard roofs shall be dimensional shingles, cedar shake, slate, or metal. Other high quality simulated examples of these materials may be approved by the ARB with examples of successful, high quality installations in comparable climates.
(6) Other roof types.
(a) Other roof types not listed as a specific type but are deemed architecturally appropriate to the proposed building may be approved by the required reviewing body.
(b) Roof terraces and roof plantings are permitted within the Historic Zoning Districts.
(c) Decorative towers that are incorporated into a building design may be permitted in the Historic Zoning Districts subject to approval of the ARB. Decorative towers are additional to and may exceed the maximum building height in the district in which it is located. The maximum width of the tower shall be one-third the width of the front façade of the building or 30 feet, whichever is less. No rooftop appurtenances are permitted on tower roofs.
(7) Roof elements.
(a) Parallel ridge lines.
1. When appropriate to the architectural character of the building, and where the principal ridge line of any building type runs parallel to any street, gabled ends, perpendicular ridge lines or dormers shall be incorporated to interrupt the mass of the roof.
2. Perpendicular ridge lines are not required to intersect the primary ridge line (i.e. the secondary roof mass may be physically lower than the primary ridge line), provided the appearance is determined to be architecturally appropriate by the required reviewing body.
(b) Dormer design.
1. Dormers shall be scaled and detailed appropriate to the architectural character of the building type. Dormer windows should be sized in relation to the windows used in the upper story, and dormers should be no wider than necessary to accommodate the window and coordinated trim. Visibility into permanently unfinished space is prohibited where dormer windows are installed.
(c) Gable ends.
1. An architecturally appropriate element such as a vent, window, or other decorative element is required on street facing gable ends.
(d) Roof penetrations.
1. Roof penetrations (fans, exhaust, vents, etc.) shall be concealed and shall not be visible from the public street frontage, unless otherwise approved by the Architectural Review Board.
(C) Entrance design.
(1) Principal entrances on all buildings shall be at a pedestrian scale, effectively address the street, and be given prominence on the building façade. This may be satisfied through the use of architectural features including, but not limited to, entranceway roofs; sidelight windows, transom window, or other adjacent windows; additional moldings with expression lines; a bay of unique width; or a raised stoop.
(2) Principal entrances on all single-family detached and single-family attached building types shall incorporate open porches or stoops unless otherwise determined by the ARB to be architecturally appropriate.
(3) Doors for commercial uses along all street frontages shall be consistent with the design of principal entrances and include glass and full operating hardware in the design of the door. Exterior doors for residential uses shall also include glass, but this requirement may be met through the use of transom and/or sidelight windows.
(4) Roll-up security grilles shall not be permitted.
(D) Windows.
(1) Windows may be wood, metal-clad wood, or vinyl-clad wood. The Architectural Review Board may approve other high quality synthetic materials with examples of successful, high quality installations in comparable climates.
(2) Highly reflective glass is prohibited. For the purposes of this section, highly reflective glass has an exterior visible reflectance percentage greater than 20%.
(3) Spandrel glass, or heavily tinted glass that impedes views into the interior of the building is prohibited.
(4) Windows shall have architecturally appropriate lintels and projecting sills.
(5) Windows shall have vertical proportions with architecturally or historically appropriate window divisions.
(E) Shutters.
(1) If installed, shutters shall be sized to provide complete coverage to the windows when closed, appear operable, and include functioning hardware.
(2) Shutters shall be wood or engineered wood. The ARB may approve other materials with examples of successful, high quality installations in comparable climates.
(F) Canopies and awnings.
(1) Awnings and canopies may be used if they function as suitable protection from the elements. To provide suitable protection an awning or canopy may encroach over the sidewalk, provided the lowest portion is at least eight feet above the sidewalk.
(2) Awnings and canopies may be mounted inside frames, above openings and/or below transoms, but installation methods shall be consistent on a building.
(3) Awnings and canopies shall be designed to be consistent with the architecture of the building and other existing awnings and canopies on a building.
(a) Awnings.
1. Awnings shall be open on the underside.
2. Awnings shall be made of durable and fade-resistant canvas, decorative metal with metal used for the internal structure, or an alternative, high-quality, durable material, if determined to be architecturally appropriate by the required review body.
3. Awnings shall not be internally illuminated but may be lighted from above by downcast fixtures mounted to the building wall.
(b) Canopies.
1. Canopies may be clad with glass, metal, wood, or a combination of these materials.
2. Canopies may be cantilevered or supported from the building wall by metal cables or rods.
3. Canopies may include downward casting light fixtures and may be lighted from above by downcast fixtures mounted to the building wail.
(G) Balconies.
(1) General.
(a) Balconies shall be a minimum open area of six- feet deep and five-feet wide.
(b) Balconies may be recessed into a building façade. Balconies that are not recessed into the façade shall be independently secured and unconnected to other balconies above and below. Balconies may not extend into a right-of-way.
(2) Juliet balconies.
(a) Juliet balconies are permitted only on upper floors of buildings where windows extend to the floor or where doors are present.
(b) Juliet balconies may project up to 24 inches and shall not extend more than six inches past the fenestration.
(c) Juliet balconies used with windows must be secured to the outside window jamb.
(H) Stoops.
(1) Stoops may be located on the front and/or corner side façades of the building.
(2) Stoops and steps shall not encroach within the right-of-way.
(I) Chimneys and vents.
(1) Chimneys on exterior walls shall be treated as architectural elements.
(2) Chimneys on exterior walls shall extend full height from the ground and vertically past the eave line and must be finished in brick or stone. Cantilevered and shed-type chimneys are prohibited.
(3) Vents shall be finished to match the color of the exterior wall.
(J) Exterior building material standards.
(1) Façade materials.
(a) Permitted building materials shall be high quality, durable materials including but not limited to stone, manufactured stone, full depth brick, brick veneer, wood siding, glass, and fiber cement siding.
(b) Other high quality synthetic materials may be approved by the required reviewing body with examples of successful, high quality installations in comparable climates.
(2) Roof materials.
(a) Permitted roof materials include dimensional asphalt composite shingles with a 25-year or greater warranty, wood shingles and shakes, metal tiles or standing seam, slate and ceramic tile.
(3) Color.
(a) Colors for all building materials shall be selected from appropriate historic color palettes from any major paint manufacturer, or as determined appropriate by the required reviewing body.
(K) Accessory uses and structures. Accessory buildings and uses are regulated per the requirements set forth in § 153.074.
(Ord. 03-21, passed 2-22-21)