A Review of Examples

The following examples provide a reference for the study of the mediating wall. Completion dates for the additions range from the mid-1970s to as recently as 1995. In this time period, all the examples are located near or after the establishment of the Secretary of the Interior's Standards and its subsequent methodology for additions to historic structures. Though not all examples necessarily fall directly under the jurisdiction of the Standards, their influence and impact on the mediating wall can certainly be recognized.

Seamen's Church Institute(92)

Located in Lower Manhattan's historically and architecturally rich South Street Seaport Historic District of New York City, James Stewart Polshek and Partners design for the Seamen's Church Institute provides a first example towards an understanding of the mediating wall. Constructed in the late eighteenth century, an existing Greek Revival merchandise warehouse building is located at the northern portion of the site for the Institute. The entire street was once crowded with these buildings, but many have since been removed and replaced by surface parking or smaller two story warehouse buildings. One of these smaller buildings was also on the site and was removed for the addition.

Illustration 19 - Seamen's Church Institute property, cleared site and remaining facade just before construction of addition.

The street facade of the Seaman's Church Institute acts as the mediating wall. The left portion of the composition contains the authentic historic facade but all other evidence of the historical fabric has been removed. Like other nearby buildings which have been demolished in favor of new uses to fulfill contemporary needs, the site of the Institute has also been cleared away with only the facade of the Greek revival structure remaining. It is this historic facade which provides the basis for a relationship to the surrounding neighborhood. Viewed in plan, the foot print of the original building appears to remain but the bearing and rear walls are actually reconstructions.

Illustration 20 - Seamen's Church Institute, James Stewart Polshek and Parners, New York, 1991.

The Seaman's Church Institute is a building clearly conceived in a twentieth century design ideology. Standing behind the street facade is a structural system derived from the Dom-Ino system of Le Corbusier. Cylindrical columns rise through the entire height of the building supporting horizontal flat slabs. Ideally, these slabs would be constructed of reinforced concrete but here, a steel frame with decking above and plaster or wallboard below the horizontal planes; a contemporary expression through available and appropriate construction techniques. This system is distinctly different from the load-bearing masonry walls and wood beam floor construction used in the surrounding historic fabric.
The Dom-Ino is not the only application of Le Corbusier's method in the building. Several others exist permitting the mediating wall to take its fullest effect: providing a sense of continuity while allowing distinctly different architectural explorations to occur at the same time. The free facade is applied to the Dom-Ino at the Institute and the decision for its expression is contextual. This facade it clad in brick to provide a sense of continuity in the South Street Seaport Historic district through a common material, color and texture. Window openings are punched into the wall and their arrangement continues the rhythmic pattern of windows and bays along the entire street. At the rear of the Dom-Ino a completely different wall assembly is installed. Translucent fiberglass allows natural light to filter into the interior while providing a weather barrier to the outside. Sections of the translucent system are replaced with transparent glass in operable window frames. This distinctly different material and assembly at the rear of the building provides a clear separation from the surrounding historic fabric.

Illustration 21 - Seamen's Church Institute, James Stewart Polshek and Partners, New York, 1991, Section.

The new brick facade of the Institute is lifted above the street level. Again, this feature can be traced to the desires of Le Corbusier, lifting the entire building above the earth to free the ground below for utilitarian purposes. For an understanding of the relationship of the addition to its historic context, the lifted facade provides two characteristics to the new building: separation and accommodation. By raising the facade, the building does not appear to be in direct connection with the historic context. All other surrounding historic buildings are required to be in direct contact with the ground due to the nature of their load-bearing masonry construction. The new addition hovers above the earth and refuses contact with the ground, the ground in which the historic past is rooted. The lifting of the facade also accommodates the historic context. Viewed in section, the street level of the building is allowed to occupy the full depth of the site. This complete occupation of the property follows the tradition of the surrounding eighteenth century structures. Above the street level, the new construction separates itself from the traditional plan configuration to accommodate light and air.

The last of Le Corbusier's methods used at the Institute is the metaphor of the ship. At the Seaman's Institute, the use of the ship conveniently coincides with the building's program. Nautical imagery is quite appropriate for an organization dedicated to the service, care and well-being of former sailors. More importantly, the metaphor of the ship as an autonomous unit allows the building to be seen as an element separated from its context. For Le Corbusier, the ocean liner is the representation of complete autonomy. The building is a unique experience unto itself. At first glance, the metaphor of the ship may seem to connect the building's new use to area's former association with a busy trading port. However, the original functions of the buildings had relatively little connection with ships when compared to their role in commerce and trade. The primary purpose of the ship metaphor is to clarify the distinction between the time periods of new and old. In the words of James Stewart Polshek, the addition is "a modern ship docked a nineteenth century pier."

As used at the Seamen's Church Institute, the thorough use of Le Corbusier's guarantees a distinction between old and new. The use of the free facade is adapted to accommodate the functions of the mediating wall. At the urban level, it provides an apparent continuity with the existing Greek Revival facade and its nearby neighbors. The mediating wall easily fits into Polshek's scheme but its use is apparent elsewhere. As in all cases, the mediating wall provides a sense of historical continuity in the existing environment while allowing other architectural explorations and functional requirements to occur beyond it, no matter how divergent these issues may be from the character of the existing environment.

Newhall Center(94)

At Mount Holyoke College in Massachusetts, an addition to a mid-nineteenth century residence was designed by Ericson Associates Architects in the early 1980s. Completed a decade before the Seamen's Church Institute, the addition uses similar architectural techniques both upon and beyond the mediating wall. The addition is an L-shaped configuration attaching to the gabled end of the existing house. Seen from the street, the weatherboards used to clad the original house and its addition present a uniform appearance and reflect the materials used on other houses throughout the area. Divided light windows, window shutters and a pitched roof are other elements suggesting neighborhood continuity. These historical elements are the items contributing to the mediating wall.

Illustration 22,23 - Newhall Center, Ericson Associates, Mount Holyoke, c.1980.

Beyond this applied skin, many indicators give notice that a different architectural method is at work beyond the historically derived elements. The L-shaped addition does not fully connect to the ground. Its distinction from the wood frame construction of the original house is revealed by being lifted upon a series of thin Doric columns. This open void frees the ground plane and creates a covered entry portico beneath the new structure. Viewed from the street, the addition could be described as a Corbusian Salt Box. The addition is raised on Doric pilotis, contains divided light windows in an arrangement recalling strip windows and is enclosed with a free facade of weatherboard cladding.

At the rear of the site, the enclosing weatherboards are pulled back to expose a metal and glass volume cantilevered beyond its supporting columns and beam but remaining beneath the covered boundaries of the roof eaves. Although radically different in aesthetic, this projecting volume does not extend beyond the plane of the elements defining the mediating wall.

Dance Theater of Harlem(95)

The Dance Theater of Harlem originally occupied a small garage which Hardy Holzman Pfeiffer Associates converted into a studio space in 1971. After twenty-five years, the success of the organization required a larger space for its home. In the expansion, the original building is maintained and the addition is located on an adjacent urban site.

Illustration 24 - Dance Theater of Harlem, Hardy Holzman Pfeiffer, New York, 1994.

Acting as an entrance marker, a glazed vertical element is situated between the new and old work creating the illusion of a transparent separation between the two. The primary configuration of the addition is treated as two interlocking masses treated with individual forms and patterns. One element is a flat topped box wrapped in strong, horizontal black and white brick bands. The other, containing the upper dance studio, is topped by a gently curved roof and clad in a multi-colored diamond pattern. The contrast of these masses along with the suggested physical separation provided by the vertical glazing guarantees a distinction from the existing, red brick-clad garage building. All of these new elements are also slightly set back from the street wall and garage facade.

To create a connection between these diversely different elements, a final piece must be installed. This final element, clad in red brick, acts as the mediating wall. Like Seamen's Church Institute and the Newhall Center, the mediating wall hovers above the ground plane never physically taking root in the ground of the existing context. This new element also remains detached and autonomous from the earlier building giving the vertical glass wall and black and white stripped box closer proximity to the original building. Its curved shape gives a final indication of difference between old and new. Only the red brick of the mediating wall with its similar window openings taken from the existing building provides a visual connection to the old garage.

The Wainwright Building(96)

Constructed in 1891, the Wainwright Building in St. Louis, Missouri is one of Louis Sullivan's masterpieces in the evolution of his theories for skyscraper design. The threat of demolition loomed over the building in the early 1970s but a concentrated effort by local and national governments, including the National Trust for Historic Preservation, found a new use for the Wainwright. In 1974, a competition was held for the renovation and expansion of the building and Mitchell/Guirgola received the commission. Delays placed the project on hold for many years but was finally completed in 1981.

Illustration 25 - Wainwright Building, addition by Mitchell/Guirgola, St. Louis, 1982.

The redevelopment of the Wainwright incorporates the building into a complex occupying the entire block with the Wainwright set as the highlight in the composition. Physical attachments to the Wainwright are only undertaken at one location. A glass atrium space attaches to the rear of the building and infills Sullivan's original light well. With the use of the transparent connector, a delicate touch is achieved with the old. A tall block equal in height to the Wainwright is also located on the backside. Circulation connections are made to the Wainwright with bridges spanning across the atrium linking the two masses, literally bridging the gap between new and old. New buildings are clad in brick with a similar color to the original and fenestration patterns are taken from the entry and balcony levels of the Wainwright Building. All masses are set far back from the street facades of the Wainwright Building. Free-standing brick screens act as urban shields between open spaces, the Wainwright Building, glass entries and the mass of the new buildings. The brick screens are completely autonomous elements. Their primary job is an aesthetic link between old and new, acting as the mediating wall. Like the new buildings, the screens take cues from the fenestration patterning of the lower two floors of the Wainwright. Following the recommendations of Camillo Boito, the patterning of these new elements are simplified and abstracted as compared to the original details of Louis Sullivan's design.

Madison Civic Center(97)

Located in the heart of Madison, Wisconsin is a civic and cultural center encompassing two previously unused historic buildings. One of the buildings is a Spanish Baroque styled movie house, the other is a Georgian styled Montgomery Wards department store. Neither building was considered to possess any outstanding architectural merit until the two facades, especially the eclectic facade of the movie house, were set off in a new composition by Hardy Holzman Pfeiffer Associates in the late 1970s.

Illustration 26 - Madison Civic Center, Hardy Holzman Pfeiffer, Madison, c.1978.

The two buildings are not immediately adjacent to one another and were surrounded by a series of lower and visually incongruent buildings. These smaller structures are removed and a wall was constructed to reestablish the street wall and connect the separate structures. The wall does not quite rise to the height of the department store and is much lower than the towering theater entry. The aesthetic of the wall is relatively neutral, acting primarily as a backdrop for the theater's tower and recalls the masonry scale and texture of both existing buildings. Behind the wall, the recollections end. On the interior, the backside of the new brick wall is seen but the material is not used to any great extent at any other area in the building. The brick is only used where it is required to visually link the historical brick of the theater and department store, an experience which generally only occurs on the exterior of the building. The interior of the existing theater is renovated but its detailing or any historical devices are recalled at no locations in the new building. The aesthetic of the new is distinctly different from the remaining historic fabric. Only the new connecting wall makes any attempt at an aesthetic connection and its true purpose is to shield the new activities behind it. In this regard, the new wall acts as the mediating wall.


Facadism allows almost the entire removal of the historic fabric of a building, retaining only the primary street facade. This element typically remains standing in its original location and is often grafted onto a contemporary building. In either case, the facade acts as a reminder of the complete structure which once occupied a position in the urban environment but has since been substantially replaced. Although often critically disregarded as a poor preservation method, the technique of facadism can be adapted quite easily for use as the mediating wall. Previous examples presented of the mediating wall employ a newly designed and constructed element recalling symbolic architectural elements. However, facadism uses an authentic historical object to act as a symbolic element to recall a condition no longer existing. It is an attempt to avert the eyes of the observer from the reality of the historic fabric's destruction and replacement.

Illustration 27, 28, 29 - Penn Mutual Tower, Mitchell/Guirgola, Philadelphia, 1975. (Far Right) John Haviland, 1835.

Constructed in 1975, Mitchell/Guirgola's design for the Penn Mutual Tower in Philadelphia retains the facade of John Haviland's Egyptian revival building of 1835. Only the stone masonry of Haviland's facade remains in place; all woodwork and windows have been removed. This remaining fragment is treated as a free standing object in the environment and is physically separated from the new building. The new facade appears to make accommodations for Haviland's facade but generally acts autonomous of it. The face of the new building is clad in glass and is another effort, most likely, to create the illusion of either transparency or reflection towards the existing context. Because of the glass, Penn Mutual appears as the insertion of a neutral and nearly invisible building deferring the conveyance of its own messages to the surrounding context. Against this transparent backdrop stands Haviland's facade, a barrier between the observer and an apparently neutral new building. Haviland's facade is the mediating wall. The design received an AIA Honor Award in 1977.(98)

Illustration 30, 31, 32 - Advertising Agency, Vincent Polsinelli, New York, 1994.

Most recently, the 1995 AIA Honor Awards recognized another instance of facadism as validated through the use of the mediating wall.(99) The accommodations for a contemporary advertising agency have been located on the site of a former butter and cheese factory originally constructed in 1871 in Lower Manhattan. The design by Vincent Polsinelli Architects retains the original facade while inserting new translucent and transparent glass surfaces behind the facade and on the roof to admit daylight into the interior spaces. The new work is distinct from the historic facade but the facade's retention allows the original character of the street to be maintained. By receiving national recognition so recently, it is impossible to disregard facadism as a valid method of additions as it is understood through the characteristics of the mediating wall.


EmailEmail home