The Commission strongly discourages the removal of original window frames and sashes from rated structures in the local historic districts. The Commission recommends that existing frames and sashes be repaired and maintained wherever possible. When replacement frames and/or sashes are necessary either because the originals are missing or not repairable, the Commission recommends the use of wood replacement sash, with details to match other existing units on the building.

The Commission has established a policy to govern the installation of aluminum or vinyl replacement windows: l. The use of storm windows on exterior surfaces of rated buildings regulated by the Commission will be reviewed on a case by case basis, either by the staff or by the full Commission. The Commission shall review applications for purple and blue-rated buildings. The staff will review the applications for green, red and gold-rated buildings. 2. The use of aluminum and vinyl replacement windows on purple and blue-rated buildings will not be permitted. 3. On green, red or gold-rated buildings where the original windows exist and are repairable, the use of aluminum or vinyl replacement windows will generally not be allowed. 4. The use of aluminum or vinyl replacement windows on green, red or gold-rated buildings where the original windows no longer exist may be considered for approval on a case by case basis. 5. The use of aluminum or vinyl replacement windows on unrated buildings may be allowed and approved at the staff level if it is determined that the addition will not damage the appearance of the district. 6. In all cases where the use of aluminum or vinyl replacement windows is allowed, all details must be submitted and approved by the Commission's staff prior to any installation. Details must be visually appropriate regarding the type, size, finish and detailing of the units.

Casement Window (elevation & section), typical of 20th century

Casement Windows.
Casement windows, hinged on the side and mounted singly or in pairs, were typical in French influenced architecture before 1830. Thus, the introduction of hung sash into buildings which predate 1830 should be avoided. Because the use of casements is associated with the early years of the 19th century, each window is usually multi-paned with generally small pane sizes. Casement windows are only rarely found on later buildings, and then only in special cases. Because casements are associated with early styles, they must not be added to a building of a later date, as this is inconsistent and has the effect of "earlying up" the building. Early casement sashes were always hung on the inner face of an exterior wall and made to swing inward. In no case should they be hung on the outside or swing to the outside. Casement windows became typical of
the earlier examples, these windows were usually mounted on early 20th century,
the exterior of the wall thickness and open out. The light pattern and Section
in these windows often used arrangements of different sized glazing units.

Double-hung Window (elevation & section), with six over two light sashes, typical of early 20th century.

Double-Hung Windows.
Double-hung windows were derived from a window form invented in Holland in the 17th century. Their use spread to England but was not widely adopted in France. Consequently, the early French influenced architecture of New Orleans did not use hung windows. With the introduction of American styles of architecture, the use of hung sash became widespread. Because hung sash is so closely identified with post-French colonial styles (after 1825), its use should be limited to buildings of that period. Double-hung sash are usually two equal sized sash, each with multi-lighted glass panes, with a window sill approximately 24" to 36" above the floor level.

Triple hung window (elevation & section), typical of 1830's

Triple-Hung Windows.
Triple-hung windows evolved from double-hung windows, but they differ in that they open to the floor. With no notable exceptions, the use of triple-hung windows was limited to the 1830s. Again, because they are so closely identified with a particular style and period, they should be preserved or restored where appropriate. Also, their use should be limited to buildings where they are stylistically appropriate. Triple-hung windows contain three (3) equally sized multi-lighted sash, which could all open to the top of the frame to allow passage through the window.

Slip head window (elevation & section) with six over nine lite sashes

Slip-Head Windows.
Slip-head windows serve the same purpose as triple-hung windows and supercede them. The distinguishing characteristic is a pocket in the head section of the frame into which part of the sash could slip. This allowed the check rail to be located above the midpoint of the opening so that when the lower sash was in the fully raised position, people could walk through the opening. Without the
slip-head feature, an opening would have to be twice as high as the height needed for clear passage.

Transom

Transoms.
Known as transom windows, these sashes are usually found in association with doors (either single or pairs). A transom is simply a multi-paneled glazed section located above the transom bar (horizontal element above door or window) and it is generally operable. This feature allows the doors to be kept locked while permitting ventilation through the open transom. Transom designs vary according to date and style, from simple rectangular sash with vertical muntins to elaborate designs. Round, segmental and elliptical transoms also are common.

Frieze Windows

Frieze or Eye-Brow Windows.
This is a type of small window located in the frieze below the main exterior cornice in buildings of the Greek Revival style. Their purpose was to give light and air to an attic floor. Glazed panels (similar to transoms) were employed, but occasionally, ornamental grilles were placed over the openings to make them more decorative.

Vitrine Window (elevation & plan)

Vitrines.
A vitrine is a display window, generally projecting from the first floor street elevation of a commercial building. Occasionally, vitrines were conceived as integral parts of an original building design, but more often they were added at a later date by taking out the sash and shutters of the original ground floor opening and filling it with a three sided glazed projection with a sheet metal roof and paneled base. Some vitrines are supported by heavy, ornamental wooden brackets projecting from the building face. Because of their high level of craftsmanship and detailing, vitrines are among the most charming of additions. Their removal should be permitted only after careful consideration of their innate worth and their effect on the building (including aesthetic and structural considerations).