Tab_10_Attachment_3_Guidelines_for_Zoning_Historical_Building.pdf

GSA New England Region 1

St. Albans Federal Building & Post Office

Building Preservation Plan

March 27, 2018

Attachment 3 – Guidelines for Zoning Historic Buildings

Attachment 3: GUIDELINES for ZONING HISTORIC BUILDINGS

I. OBJECTIVES

A. The Building Preservation Plan consists of three parts:

History and Documentation

Analysis and Findings

Recommendations

Analysis and Findings includes one of the fundamental elements of the

BPP: building zoning. Zoning, in brief, consists of dividing the exterior and interior of a building into areas based upon the relative historic and architectural significance or value placed upon them.

B. The process of zoning requires professional judgement and an understanding of the purpose of the BPP program. The decisions relative to zoning are generally based on visual observations of the interior and exterior architectural elements and element groupings. Identifying and displaying zones which require defined levels of treatment will be an important step toward ensuring that proper care and treatment are applied to significant areas. It will also provide building management staff with clear information about which areas are open to greater degrees of modification.

C. Zoning is a visual process, requiring a graphic base; therefore, plans and elevations of all areas will be required by the BPP. Professionals zoning historic buildings will be required to produce plans and elevations in

AutoCAD.

1. The Contracting Officer's Representative will determine the specific version of AutoCAD required for this contract.

II. ZONING HISTORIC BUILDINGS

A. The daily operation and maintenance of a historic building requires specific information on the architectural design and elements of the building. Some building elements and finishes are historically significant and represent a sizeable investment; therefore, they require specialized treatment. Information on which elements and zones fall in this category is needed to maintain the buildings in a manner that reflects their historic significance. Zoning information should distinguish between areas of the building that may require different types of treatment.

B. The process of zoning establishes a framework for operation and maintenance by dividing the building into areas consistent with their original design, use, public access and integrity. The concept of zoning, which establishes a framework for operations, maintenance and rehabilitation, is also consistent

Building Preservation Plan with techniques of original architectural programming and design, where primary facades have richer detailing and material than secondary facades.

Interior spaces also are traditionally zoned into public, private, and circulation spaces. Areas of public access, ceremony or authority typically receive richer detailing and finer materials than the more common work or private areas.

C. The zoning of the building will seek to recognize and identify the delineators between more and less significant interior and exterior building areas and to assign a classification to each. The following descriptions establish a series of architectural zoning criteria to be used to sub-divide the building into areas with differing maintenance and preservation requirements. The zone ratings establish management and treatment requirements for each area. Highly significant public areas, for example, will be in a "restoration zone" where maintenance is tightly controlled and alterations restricted. At the other end of the spectrum, larger more typical work areas may fall into "rehabilitation" or

"renovation" zones subject to normal maintenance and open to a much broader range of architectural modification.

III. ZONE CLASSIFICATIONS

A. The zoning process establishes values for different areas of the building. The process is qualitative and often there may be different judgments regarding zone values. Every attempt has been made in this section to provide guiding language to explain the factors that distinguish one zone from another. Zone ratings should be made based on which definition seems closest to the conditions of the zone(s) under evaluation. Interpretations of the definitions, when requested, will be provided by the Center for Historic Buildings, Office of the Chief Architect.

B. The following designations shall be used for zoning historic buildings.

1. RESTORATION ZONE:

These areas exhibit unique or distinctive qualities, such as original materials or elements, representative examples of skilled craftsmanship, or the work of a notable architect or builder. They may also be of significance due to associations with persons or events of preeminent importance.

a) Examples: Spaces or areas of a building representing the highest degree of detailing and finish, such as the main lobby or public spaces in a hotel or office building; the foyer and parlors of an historic residence; executive offices in public buildings, i.e., judicial chambers, Cabinet-level or Secretarial level offices; and assembly spaces, such as courtrooms, libraries or auditoriums

b) Guidelines: The character and qualities of this zone should be

Building Preservation Plan maintained and preserved as a highest priority. These are areas of special architectural and/or historical importance, and are recommended for complete restoration.

2. REHABILITATION ZONE:

These may be spaces or areas exhibiting distinguishing qualities, original materials and/or elements, but less ornate than restoration zones in overall treatment.

a) Examples: Spaces or areas less rich in materials and detailing than principal public spaces, assembly spaces or executive offices. These may include secondary circulation spaces, secondary offices, smaller meeting rooms.

b) Guidelines: Spaces in this category may be rehabilitated, but every effort should be made to identify and retain original material wherever possible. New materials may be introduced, but should be done so in as sensitive a manner as possible to permit retention of the general character of these spaces.

3. RENOVATION ZONE:

These are areas whose renovation and modification would not represent a loss of historic character, or intrusion to an otherwise historically significant structure.

a) Examples: Undistinguished or repetitive areas such as typical offices, open office landscapes, utility rooms, storage closets or ancillary spaces (except where these are clearly related to more significant spaces, and thus form a part of a larger ensemble of spaces).

b) Guidelines: Treatments in spaces zoned under "renovation" may incorporate extensive changes and the introduction of contemporary construction methods, materials and designs, although every effort should be made to design such treatments in a manner sympathetic to the historic qualities and character of the building.

IV. GUIDELINES FOR ASSIGNING ZONES

A. In reviewing criteria for applying a zone to each area of an historic building, it is important to consider the building's historical context. Understanding when and why a building achieved significance is important in determining the proper approach to its zoning. On the surface, some buildings, materials or architectural details may appear mundane, however, they may be as important as a richly detailed, high-style structure. Buildings associated with important persons or events often fall into this category. Understanding the history and context of a building is as essential as the ability to identify architectural

Building Preservation Plan styles, materials and architectural terminology.

B. The process of zoning a building is a qualitative process, relying on visual understanding and research into historic context, rather than a quantitative tabulation of elements or materials. Professional training and experience are required to be able to intuitively recognize historic and architectural merit as it is reflected in the design and construction of each building. Judgments may be made "at a glance' by professionally trained individuals, but will require substantial effort and research by persons without proper training.

C. Once an initial inspection has been completed, the inspector may then consider an approach or philosophy for zoning. Oftentimes, the simplest and most straightforward approach may be the best -floor by floor. In other applications, a functional breakdown may be preferable. In this case, it is recommended that the inspector adhere to the primary, secondary and tertiary grouping approach. Begin with the most significant spaces and end with the least important ones. It is desirable to group duplicate spaces where plan, detailing and material applications are the same. An example of this approach would be "elevators lobbies in non-ceremonial spaces". In any building there may be conditions or elements that require exception. Examples may include special elevator lobbies, atriums, light wells, mechanical spaces and penthouses.

D. One crucial consideration for the inspector to be aware of is the ability to identify quantifiable characteristics that make the building significant.

Examples of this include spatial sequences and flows. While examining the building, and prior to assigning zones, the inspector should be cognizant of its plan, spatial sequences, details and materials. During the walk-through, the inspector should note significant details and ornamentation, materials and the ways in which they employed, room groupings (e.g., courtrooms with ancillary support spaces), and unusual conditions or anomalies. Unusual conditions or anomalies are worth noting either for their contribution to the building's character, or conversely, as intrusions resulting from insensitive alterations.

E. The exterior of the building is the simplest to zone. Standard compass designations such as "north" should be used, combined with qualitative descriptions, such as primary, secondary, rear, courtyard, etc. In other instances, massing designations such as "center wing" may be used. In all cases, the zoning classifications should be clear and easily understood.

F. The mechanical, electrical, plumbing and other utility systems of a building should not be overlooked. Where significant mechanical systems and elements exist, and merit special treatment, mechanical areas may be zoned as "restoration" or "rehabilitation" zones. Otherwise, individual elements, such as decorative light fixtures, original toilet room fixtures, and radiators

Building Preservation Plan and mechanical supply grilles should be identified as contributing elements to the spaces in which they are located, and treatments recommended accordingly.

G. The following process will be helpful in establishing the zone ratings:

1 Become familiar with the BPP program design.

2 Collect accurate floor plans and elevations of the building, and photographs of areas and features.

3 Using the plans and information gathered on the building's design, construction and function identify logical areas or spaces based on major function of activity. Keep in mind that these areas of related function or design may be vertical as well as horizontal.

4 Compare the location, density and/or richness of architectural finishes and details with the major functional divisions identified in Number 3 above.

5 Delineate contiguous areas in the building where there is a consistent level of detail, quality and richness of elements and finishes.

6 Assign an appropriate zone level rating to each identified zone.

H. In the end of the zoning process, all elevations and interior spaces shall have one of the three zoning designations assigned to them. This will serve as the foundation for the treatment recommendations to follow in Part 3 of the BPP.