The Columbia historic preservation commission applies general standards derived from the Secretary of the Interior's Standards for Rehabilitation, adopted and supplemented by local standards, to fit specific situations encountered in Columbia. To ensure that everyone, commission members and property owners alike, have an equal understanding of the standards that are applied, the following guidelines are provided, based on the Secretary of the Interior's Standards and past actions by the Columbia historic preservation commission. The decision to approve or deny an application for a certificate of appropriateness shall include, but not be limited to, the following considerations:

    A.    A reasonable effort shall be made to use a building, structure or site for its originally intended purpose, or for a purpose requiring minimum alteration to the premises.

    B.    The compatibility of proposed new additions or construction to the original architecture of the landmark or styles within the historic district shall be evaluated against the following guidelines:

    1.    The key to successful rehabilitation is in maintaining characteristic details and the historic fabric of a structure.

    2.    When introducing new exterior elements, materials equivalent to those already existing on the structure should be used.

    3.    Buildings should not be made to look either older or newer than they really are by using details from another style or period.

    4.    Original materials or details should not be removed from a building when they can be repaired.

    5.    The distinctive historic and architectural character of a building should be retained through regular maintenance and repair.

    6.    Paint Color. Property owners are encouraged, although not required, to submit plans to the Columbia historic preservation commission for paint preparation and color selection.

    a.    In selecting paint colors, consider what is stylistically appropriate for the period of the architecture and how color selected will blend with other buildings on the street.

    b.    Generally, the number of colors for the exterior should be limited in keeping with the original style and with other buildings within the historic district. Light colors visually reduce the massiveness of a wall and absorb less heat. White, however, unless appropriate to the original architectural style, is not recommended for wall surfaces because it is overly bright and tends to draw attention rather than blend in with surrounding buildings. White may be more appropriate as an accent color.

    c.    Avoid bright or brilliant tones as dominant building colors.

    d.    Use color to accent important detail.

    e.    Brick, stone or other masonry should not be painted unless the material has been painted before. Wood surfaces which are stained should continue to be stained and not painted. Other wood surfaces should be painted and not left untreated or allowed to "weather" in appearance. Paint should not be removed from materials which were originally painted.

    7.    Cleaning of Structures. The Columbia historical preservation commission is available for advice at the owner's request.

    a.    Cleaning of materials should be done by the gentlest means possible.

    b.    Sandblasting and other abrasive cleaning techniques should not be used.

    c.    Any material destroyed or damaged in the cleaning process should be replaced by equivalent material; e.g., wood siding should be replaced by wood siding.

    8.    Wood. Destructive, dangerous and/or abrasive cleaning techniques, such as propane torching and sand or water blasting, should not be used.

    9.    Masonry. Sandblasting or the use of harmful, destructive chemicals should not be used.

    10.    Landscape. A certificate of appropriateness is required only if one of the following is true.

    a.    Another city permit is required (such as landscaping required by zoning for parking lots); or

    b.    A tree greater than fourteen (14) inches in diameter is to be cut down (trees of that size have existed long enough to be considered important elements of the overall environment of a landmark or historic district, and hence are worth protecting).

    11.    Roof Repair or Replacement.

    a.    The original shape pitch, eaves lines and ridge should be retained or restored.

    b.    The original roofing material should be retained and duplicated, whenever possible. When not possible, materials should be used that are compatible with the original in texture, basic material and color.

    c.    Adequate drainage and weather-tight covering should be provided.

    d.    When replacing deteriorated roofs, whenever possible new materials should match the old in composition, size, shape, color and texture.

    e.    Necessary roof-mounted architectural features such as dormers, cupolas, cornices, brackets, chimneys, cresting and/or weathervanes should be preserved or replaced.

    f.    Gutter or downspout materials should be appropriate to the building on which they are located and have the same size, shape, texture and material as the historic gutter and downspout systems.

    12.    Existing dormers should be maintained in original size, shape and placement, unless the owner can show they were not part of the original structure and that they have not become significant parts of the design of the structure, or its history.

    13.    New dormers:

    a.    Should match the original architectural style and materials of the structure;

    b.    Should be located as to preserve the original balance and massing of the structure;

    c.    Should be compatible with existing dormers in proportion, slope and design.

    14.    Windows and Doors.

    a.    Window and door openings should be kept in their original size and spacing.

    b.    Original openings and trim, including sash, glass, lintels and sills, architraves, doors, pediments, hoods, steps and hardware should be repaired and reused.

    c.    The original style of windows should be retained.

    d.    When original material is deteriorated, original material and design should be duplicated in new sash and door work.

    e.    When used, substitute materials should be as unobtrusive as possible and removable in the future.

    f.    Use of snap-in mounting bars and similar items should be used only in noncontributing properties.

    g.    Use of raw aluminum for storm windows and doors is strongly discouraged.

    h.    Contemporary door designs, such as flush doors, not appropriate to the style of a historic building, should not be used.

    i.    Replacement doors should match the historic doors in material, size and style; have the same series of panels; and have a frame of the same dimensions.

    15.    Siding.

    a.    Original materials should be retained.

    b.    Mortar should only be repointed when there are moisture problems or where mortar is missing.

    c.    Mortar should not be routed with electric devices because it may cause damage to adjacent masonry.

    d.    Original mortar should be duplicated in terms of composition, color and texture.

    e.    Original mortar joint profiles in all weathering joints should be retained.

    f.    Original materials should be duplicated when replacing deteriorating masonry.

    g.    Missing architectural elements, i.e., cornices, brackets, railings, porches and shutters, should be replaced.

    h.    Masonry that has not been painted before should not be painted.

    i.    Masonry and wood that were originally painted should be painted.

    j.    Vinyl or aluminum siding will be allowed only on structures built after such materials were generally available. If such siding is used, it should match the original in appearance (spacing and direction) and decorative trim and cornerboards should be retained.

    k.    Synthetic or modern replacements of original materials such as aluminum, fiberglass or epoxies should not be used other than for stabilization, consolidation or conservation of original materials.

    16.    Existing Chimneys. When rebuilding or repairing existing chimneys, existing material and design should be matched, unless it can be shown that this differs from the original construction, in which case that may be used as the model instead.

    17.    Additional chimneys: Must match existing ones in material and basic design.

    18.    Porches and decks:

    a.    Should be compatible with the main structure in materials and scale;

    b.    Vertical elements (e.g., railings) should be painted to be compatible with the main structure; decking may be stained or painted to match railings, etc.;

    c.    Original work/details should be retained whenever possible.

    19.    Fences.

    a.    Style should be appropriate to the house.

    b.    Use of chain link is discouraged; when used, it should be painted black or dark green to make it as unobtrusive as possible. Plastic fencing will be allowed.

    20.    Garages.

    a.    Pitch of the roof on a new garage should match that of the house, unless specific problems prevent it (such as houses with extremely steep pitch, which would result in a garage too high to meet zoning requirements).

    b.    Siding should match that of the house unless the house is brick; then wood is allowed as an alternative.

    c.    Service doors and windows should match those on the house in design.

    d.    Plain flush garage doors should match those on the house in design.

    21.    Ramps. Railings for ramps installed to provide handicapped accessibility should match similar elements on the structure.

    22.    Skylights. Use of skylights that are visible from the street is discouraged. Those that are not visible do not require a certificate of appropriateness.

    23.    Solar collectors allow homeowners to utilize modern technology while preserving the home.

    24.    Satellite dishes are strongly discouraged. If they must be used, they should be as unobtrusive as possible.

    25.    Swimming pools.

    a.    Permanent above-ground pools are strongly discouraged.

    b.    Fencing around in-ground pools must be reviewed by the Columbia historical preservation commission.

    26.    Signs. Refer to Chapter 15.44 to regulate signs on historic landmarks and/or in historic districts.

    27.    Additions:

    a.    Should match the material, window spacing and roof pitch of the main structure;

    b.    Impact of the addition should not overwhelm the main structure;

    c.    Significant historical materials and features should be preserved and not covered up with the addition.

    28.    New Construction. The focus of design guidelines for new construction is on ensuring the compatibility of the new with what already exists in the immediate vicinity. These design guidelines are not intended to dictate style but to set up criteria under which any new designs can be objectively compared with the setting of the particular historical district. It is strongly recommended that owners of buildings consult with the Columbia historical preservation commission in the early planning stages of a new construction project. New construction should be compatible with existing structures in the immediate area in the following ways:

    a.    Size, height and setback of structures;

    b.    Relationship of the structure to the open space between it and neighboring structures;

    c.    Exterior features, such as window sill or header lines, the proportion of window and door openings to the overall facade, and the horizontal or vertical emphasis of major building elements; and

    d.    Building materials.

    29.    Demolition of historical buildings irreversibly alters the character of the individual site, streetscape, building or district grouping. Demolition of buildings and structures in historical districts or of landmark structures should be a last alternative when all other avenues of protecting historic buildings and structures has been exhausted. Demolition is not permitted within historical districts or on historic sites unless one of the following conditions exist:

    a.    The demolition request is for an inappropriate addition, a nonsignificant portion of a building, or nonsignificant accessory structure, provided the demolition will not adversely affect those parts of a building or buildings which are significant, as determined by the Columbia historical preservation commission; or

    b.    The demolition request is for a noncontributing building and the demolition is required by the public safety because of an unsafe or dangerous condition; or

    c.    The building official of the city certifies that the demolition is required by public safety because of an unsafe or dangerous condition; or

    d.    The property owner shows that failure to allow demolition would create a substantial hardship, financial or otherwise, pursuant to ordinance provisions for hardship; or

    e.    The property owner shows that no reasonable economic return may be gained from the property.

    30.    Vacant Lots. Any vacant lots within a district should be sodded or seeded with grass, and the grass kept cut to acceptable standards for a residential neighborhood. (Ord. 1527 § 2, 1996: prior code § 41-5-5)