Development of Standards and Guidelines
In the United States, the first binding guidelines for appropriate additions were passed in 1978 as the Secretary of the Interior's Standards for Historic Preservation Projects.(54) These standards were more specifically interpreted in the Guidelines for Applying the Standards, published in 1979. The need for these standards and guidelines was a result of the various tax credit incentives for historic preservation requiring a set of guiding criteria to determine eligibility for the tax credits, the most significant of which were available from 1975 to 1985. Before the passage of the Secretary of the Interior's Standards and Guidelines, no codified and binding document existed for the treatment of additions to historic properties in the United States.
The first suggestion of the method for appropriate additions was written in the Venice Charter in 1964.(55) The charter is primarily the culmination of several Italian and European preservation theories but conceived at an international level. This encompassing document is then allowed interpretation by individual national requirements and cultural needs. The source of the Venice Charter lies in the Athens Charter of 1931. As suggested by George Skarmeas, the work of Camillo Boito at the end of the nineteenth century was an attempted synthesis of the subjectivity of Viollet-le-Duc and the perceived negativism of the anti-restorationists. Boito's principles for restoration served as the basis for the work of G. Giovannoni who set the foundations of the Athens Charter.(56) Like Boito's work, the Venice Charter contains many direct association to the writings of Ruskin and Viollet-le-Duc and also begins to suggest appropriate methods for the design of additions.(57)
The first directions are given in Article 1 in which the term monuments "...shall refer not only to a single architectural creation, but also to its setting. A monument is inseparable from its environment and the history to which it bears testimony."(58) The issue of a building's setting and the protection of the setting arises throughout the language of the Venice Charter as an imperative for protection. Not only does the building suggest a particular historical association, but also the environment it is situated within. A change in that setting could result in a distorted or different interpretation of the building's apparent significance. This is an essential first step in understanding the evolving attitude of additions to historic structures. As Ruskin suggested in regard to the untouchable monument, the historic building can not be modified. Modifications or alterations, either to the building or its setting would alter the building's significance as determined by its particular historical moment. The building and its context must exist as an individual entity and not re-interpreted by contemporary ideas or interventions. Thus:
Additions may be permitted only in so far as they do not interfere with any of the essential parts of the structure, its traditional setting, the balance of its design, and its relation to its surroundings.(59)And,
The safeguarding of a monument implies the safeguarding of its traditional setting; additions, removals, or repairs may not, then, change the relations of size and color.(60)Although not necessarily limited to the physical realm, the regard for the historic context is also suggested by the United States National Register:
The use of the historic context allows a property to be properly evaluated in a nearly infinite number of capacities... The key to determining whether the characteristics or associations of a particular property are significant is to consider the property within its historic context.(61)Therefore, no discontinuity can exist between the historic object and the setting that it is located within. Only a cohesion within the building's environment can assure a proper interpretation of the building in regard to its particular period of significance. Any building addition must to be sympathetic to this pre-established context:
In relating to a historic district the mold has been cast in the past, and the very predominance of the assemblage from the past makes it necessary that the new fit into the background and relinquish the foreground to the mass of the old.(62)But through this method, a conflict arises. If the addition is to pay homage to the original historic artifact and integrate with its setting, it must adopt an aesthetic which is sympathetic or referential to that established context. However, the addition must also be somewhat distinct from that setting in order to avoid creating a false historical context which underminds or is a false interpretation of the original. Although Article 8 of the Venice Charter focuses upon the insertion of new elements in the restoration process, the suggestion applies equally to any addition to a historic structure:
The elements... should be harmoniously incorporated into the whole, but at the same time be distinguishable from the original parts in order that the restoration may not falsify the record of art and art history.(63)This is the ultimate dilemma of the appropriate addition, integration versus separation; the Ruskinian integration of forms and materials versus respect (or isolation) of the determined significance of the historic context from the influence of change or reinterpretation.
Illustration 6 - Yale Art Gallery, New Haven, addition by Bolt, Beranek & Newman, 1976. The true subservient addition: out of sight underground.
A second international meeting took place eight years after the Venice Charter was written. "The Resolutions of the Symposium on the Introduction of Contemporary Architecture into Ancient Groups of Buildings" were written at the Third ICOMOS General Assembly in Budapest in 1972. While realizing the possible need for programmatic changes in the continued use of historic structures, the symposium further recognized the autonomy of the historic site as its significance had been determined at a particular moment in time. Also introduced were key architectural characteristics which can be used to assure the subservience of new construction to the historic. As stated in the conclusions adopted:
...contemporary architecture, making deliberate use of present-day techniques and materials, will fit itself into an ancient setting without affecting the structural and aesthetic qualities of the latter only in so far as due allowance is made for the appropriate use of mass, scale, rhythm and appearance.(64)If a contemporary aesthetic is used for the addition, it must be regulated in a way that does not overpower the original artifact. It must be modified to play into the "mass, scale, rhythm and appearance" of the original building. Thus, the historic artifact always takes a higher level of meaning than any addition could possibly attain. The original is to be treated as the precious gem of culture's production which can never be improved upon.(65) Once again, its mere status as a superior holder of age-value allows the historic artifact to take precedence and suggest the direction for any future modifications. Its status as a holder of age-value also guarantees its separation from any new addition which contains no age-value. This is despite a modern, Reigelian desire to attain a coexistence between age-value and newness-value.
In December 1977, the National Trust for Historic Preservation sponsored a symposium addressing the issue of additions to historic structures, especially directed towards the American context, entitled "Old and New Architecture: Design Relationship." The symposium was organized in response to the sudden growth work in the preservation field created by recently established federal government tax incentives and was a precursor to any government standards. Many papers were presented and later published. All followed a similar theme and expanded upon the symposium and published document of ICOMOS in 1972.
Illustration 7 - Prudential Tower behind the Boston Public Library.
A presentation made by Jean Paul Carlhian identified three important physical criteria which must be carefully considered in the design of new buildings to reduce their impact on the existing context. These factors are height, surface covered and mass.(66) A new building's greater height, over a surrounding environment of generally uniform height, or greater footprint, as compared to smaller adjacent buildings, will greatly detract from the established character of a particular built environment. The combination of height and surface covered establish the overall mass of the new building. The architectural treatment of this mass will also greatly affect the degree of visual impact upon the surrounding environment. In one of several comparisons, Carlhian contrasts the "ponderous," "squatting" and "clumsy" mass of the Prudential Center Tower, seen over the Boston Public Library, to the "slenderness" of the Hancock Building, across from H.H. Richardson's Trinity Church. The Hancock tower's rhomboid configuration and site placement prevent the building's mass from imposing too greatly upon the church and its square despite its greater height and area covered. The facade of the Hancock Tower is directed away from the church while the base responds to the established cornice height of the area.
Illustration 8 - Hancock Tower, I.M. Pei, Boston, 1976.
In a separate presentation, Giorgio Cavaglieri also comments on the Hancock Tower along with another similarly sized structures in New York City, the Olympic Tower, near St. Patrick's Cathedral, and the Pan Am Building, near the New York General Building (now the Helmsley Building). The new buildings create a distinctly new environment for a historic structure nearby due to their incredible size. The smooth glass surfaces of the Hancock Tower and Olympic Tower "seem to emphasize the elaborate shape and decor of the older buildings and enhance them with the play of reflections" while the Pam Am Building fails this accomplishment because of its close repetition of the color and texture of the materials of the nearby historic building. Cavaglieri makes certain to state that the characteristics of the Hancock and Olympic Towers "should not be interpreted as a call for smoothness or flatness" but instead requests appropriate physical distance and neutrality of aesthetic be given to new buildings near historic architecture. This is the failure of Pan Am; the qualities of the historic building are lost in the density of the building's aesthetic expression and its overpowering physical presence blocks the silhouette of the historic building against the sky.(68)
Cavaglieri's observations reveal one of the two choices which begins to emerge from the symposium as the method for proper additions to historic structures. Defined by Mark Alan Hewitt, these two methods are the theory of disjunction and the stylistic unity theory. As suggested by Cavaglieri, the new building should be a separate and abstracted item in the historic context. Historical imitations are improper. Hewitt's disjunctive theory states: "...old buildings are best served by being left alone, separate and distinct from new architecture, which should obey the imperatives of its own historical moment."(69) Glass objects such as the Hancock Tower are seen as neutral objects in the environment possessing limited impact on the surrounding context. A presentation by Peter Blake clearly outlined methods of the disjunctive theory with three modes of design in historic contexts: the invisible addition, the anonymous addition and the polite deception. As the titles suggest, none of the methods attempt to engage the historic fabric in any way. Instead, all methods create a new architecture remaining autonomous, isolated and even hidden from the existing context. The disjunctive theory is the most highly advocated method presented during the symposium.
On the other hand, the stylistic unity theory aims at creating a building which is integrated into its surroundings. The theory is rooted in the restoration practices of Viollet-le-Duc where the individual building is restored to a state of completion which it may never have known before. It is an attempt to authentically complete the building's determined historical period of significance.(70) The theory of stylistic unity can be linked to John Ruskin as well. Ruskin believed new architectural construction should be produced only from materials which will gain the beauty of age through weathering and the passage of time. If this method is followed completely, a visual unity not just of the single building but of the entire built environment will eventually be created and maintained. The stylistic unity theory as defined from the work of Viollet-le-Duc is often critically disregarded for the fear of either blurring the boundaries between what is old and new or creating a false, historically enslaved and derived architecture. Even so, false historical fronts often escape criticism and receive praise when linked to the greater scope of unity suggested by Ruskin.(71)
During the "New & Old: Design Relationship" symposium, buildings were presented which could easily be placed into the stylistic unity theory as derived from a broader context. These examples are located within a historic neighborhood or district and do not necessarily respond to a particular historic building. For example, the features of nineteenth century houses of Arrow Rock, Missouri are mimicked in recently constructed residences. Many of these new houses originate from plan catalogs and are adapted to suit match the aesthetic desires of the town.(72) A townhouse constructed in Georgetown also makes direct reference to the aesthetic of the houses in the neighborhood.(73) In the Vieux Carré district of New Orleans, several hotels were designed to integrate into the surrounding architectural environment with the application of directly copied historical elements.(74) In all cases, a direct replication of the materials and elements of the surrounding architecture are adopted to achieve a visual continuity with in a regulated historic district. Because these buildings contribute to a more generalized environment rather than a specific building, the works are accepted.
Illustration 9,10 - Row House, Georgetown, addition by Hugh Newell Jacobsen, c.1963. Street facade responds to existing context.
When both the disjunctive and stylistic unity theories are addressed at the same time, ambiguity and uncertain direction are the result. This uncertain relationship is expressed in the 1978 Secretary of the Interior's Standards for Historic Preservation Projects:
Contemporary design for alterations and additions to existing properties shall not be discouraged when such alterations and additions do not destroy significant historic, architectural, or cultural material, and such design is compatible with the size, scale, color, material, and character of the property, neighborhood, or environment.(75)This standard closely resembles one of the resolutions of the ICOMOS symposium in 1972. The later portion of the standard attempts to achieve a stylistic unity between old and new through the manipulation of the new building's size, scale, color, material and character. In this way, old and new can be blended together to prevent any disruption of the historic context. At the same time, a separation must exist between new and old to avoid damage or alter the interpretation and understanding of the historic structure and its context. "All buildings, structures, and sites shall be recognized as products of their own time."(76) Infringement on that distinct time can not be allowed. Following the lead set in the "Old & New: Design Relationship" symposium favoring the disjunctive theory, the Guidelines for Applying the Standards, first published in 1979, recommends "using contemporary designs which are compatible with the character and mood of the building or the neighborhood" but does not recommend "imitating an earlier style or period of architecture in new additions except in rare cases where a contemporary design would detract from the architectural unity of an ensemble or group."(77)
The Guidelines were revised in 1983 but the changes only blurred the division between the theories of disjunction and stylistic unity. The building is treated as an isolated fragment of history as described by the theory of disjunction while, at the same time, a degree of stylistic unity must also be present. A recommendation requires the consideration of both by:
Considering the attached exterior addition both in terms of the new use and the appearance of the other buildings in the historic district or neighborhood. Design for the new work may be contemporary or may reference design motifs from the historic building. In either case, it should always be clearly differentiated from the historic building and be compatible in terms of mass, materials, relationship of solids to voids, and color.(78)Following the theory of disjunction, "new design should always be clearly differentiated so that the addition does not appear to be a part of the historic resource."(79) New work can not alter the determined significance of the historic property and must be separated from it as required by the theory of disjunction. The historic environment should be distinct from new construction to maintain a sense of autonomy, free from the influences new interpretations may have upon its determined significance. However, new work must also be compatible with the historic conditions of the building and environment as required by the stylistic unity theory. This unity applies not only to the historic building or property itself, but to also to the greater surrounding environment. Frequent emphasis is placed on the compatibility of new building in terms of the size, scale, design, material, color and texture of the surrounding environment. The problem of the addition remains: separation versus integration.
In 1995, both the Standards and Guidelines were substantially reorganized in an effort to promote a better public understanding of preservation work and provide a hierarchal framework for different levels of preservation treatments. The essential intention of the Standards and Guidelines remains relatively unchanged, only its language has been altered in an effort for an easier understanding. The desire for both the disjunctive theory and stylistic unity theory still remains:
New additions, exterior alterations or related new construction will not destroy historic materials, features and spatial relationships that characterize the property. The new work will be differentiated from the old and will be compatible with the historic materials, features, size, scale and proportion, and massing to protect the integrity of the property and its environment.(80)