Definitions - B

BA - Biological Assessment

Basic Hydrologic Data
Includes inventories of features of land and water that vary only from place-to-place (e.g., topographic map, geologic map), and records that vary with both place and time (e.g., records of precipitation, streamflow, groundwater, quality of-water analyses.) Basic hydrologic information is a broader term that includes surveys of the water resources of particular areas and a study of their physical and related economic processes, interrelations and mechanisms.

Basis of Design Report (BDR)
Narrative that describes in detail the building, site, and utility design, including: structural, mechanical, electrical, water, and wastewater systems; energy analysis; and materials analysis. The BDR should be detailed enough to allow an accurate Class B Construction Cost Estimate to be prepared and is a stand-alone document that provides the basis for preparing Design Development documents and Design-Build Request for Proposal's (DB RFP).

BDR - Basis of Design Report

Beneficial Occupancy
The project, or portions thereof, are complete in nature to allow the government to utilize the project, or portions thereof, for their intended usage. The mechanical systems, life safety systems, telecommunications systems, and any other systems which are required to properly utilize the project, or portions thereof, shall be complete and in good working order. The remaining items to be completed shall be such that the correction does not cause inconvenience to the government or disruption to the government's normal operations. The one year warranty period begins on the date we take beneficial occupancy. If you have more than one date of beneficial occupancy for different systems, or work segments, you will end up with multiple warranty periods.

Best Management Practices (BMPs)
Practices that apply the most current means and technologies available to not only comply with mandatory environmental regulations, but also maintain a superior level of environmental performance. See also, "sustainable practices/principles."

Bibliography (Historic Structure Report)
The bibliography is an alphabetical listing of sources, divided by subjects into sections or it may be annotated with a brief description of each listed source. As a scholarly work, an HSR's bibliography will include all documentary sources that were consulted for the preparation of the document. The format of the bibliography should conform to the Chicago Manual of Style as specified in the Cultural Resources Management Guidelines. (Chicago Manual of Style, 1982, 29)

Also referred to as sealed bid. An offer in response to an invitation for bids. (FAR 2.101)

Bid Documents
All the documents required to bid or negotiate the construction agreement (contract). They are the construction documents with two exceptions: bid and contract terms which are not executed and contract modifications. (AIA)

Bid Opening
For unclassified bids, the bid opening officer (or delegated assistant) must decide when the time set for opening bids in the solicitation has arrived and inform those present of that decision. The bid opening officer (or delegated assistant) must:

  • Personally and publicly open all bidsreceived before that time.
  • If practical, read the bids aloud to the persons present.
  • Have the bids recorded. The original of each bid must be carefully safeguarded, particularly until the abstract of bids has been made and its accuracy verified.
  • Permit the examination of bids by interested persons if it does not interfere unduly with the conduct of Government business.(FAR 14.402-1)

Any person who has submitted a bid in response to an invitation for bids.

Bilateral Modification
A contract modification that is signed by the contractor and the Contracting Officer. Bilateral modifications are used to:

  • Make negotiated equitable adjustmentsresulting from the issuance of a change order;
  • Definitize letter contracts; and
  • Reflect other agreements of the parties modifying the terms of contracts. (FAR 43.103(a))

Biological Assessment (BA)
Biological assessment - information prepared for the U.S. Fish and Wildlife Service by, or under the direction of, a Federal agency to determine whether a proposed action is likely to:

  1. adversely affect listed species or designated critical habitat;
  2. jeopardize the continued existence of species that are proposed for listing; or
  3. adversely modify proposed critical habitat.

Biological assessments must be prepared for "major construction activities" considered to be Federal actions significantly affecting the quality of the human environment as referred to in the National Environmental Policy Act of 1969 (NEPA) (42 U.S.C. 4321 et seq.) An agency is not required to prepare a biological assessment for actions that are not major construction activities, but, if a listed species or critical habitat is likely to be affected, the agency must provide the Fish and Wildlife Service or the National Marine Fisheries Service with an account of the basis for evaluating the likely effects of the action. The outcome of a biological assessment determines whether formal consultation or a conference is necessary. [50 CFR §402.02, 50 CFR §402.12]

Biological Opinion (BO)
A document which includes:

  1. the opinion of the Fish and Wildlife Service or the National Marine Fisheries Service as to whether or not a Federal action is likely to jeopardize the continued existence of listed species, or result in the destruction or adverse modification of designated critical habitat;
  2. a summary of the information on which the opinion is based; and
  3. a detailed discussion of the effects of the action on listed species or designated critical habitat. [50 CFR §402.02, 50 CFR §402.14(h)]

BIP - Bridge Inspection Program

BMPs - Best Management Practices

BO - Biological Opinion

Tools to provide the Government, subcontractors, and suppliers with assurance that should the contractor be financially incapable of making payments, fulfilling contractual obligations, or completing the contract, there will be a financially solvent party (the surety) available to fulfill these obligations.

Bridge Inspection Program (BIP)
A FHWA program, which is required by federal statute, it inventories and inspects the condition of all bridges in the Federal-Aid Highway system. An evaluation of each bridge's load-carrying capacity is performed to determine if any deficiencies exist, and if necessary, appropriate action such as warning signs, bridge closing, rehabilitation or replacement, is taken. Information can be found at the following website: (pdf).

Building Character
In order to assess a building's character, we rely on the same three step visual analysis published in Preservation Brief 17 as a tool for assessing and identifying architectural character (visual aspects) of either proposed or existing individual buildings or groups of buildings. This process shall also be applied to assess the character and context of all immediately adjacent, regional, and culturally significant buildings that might influence or directly contribute to the vicinity's vernacular architecture.

Description of Existing: Relying on the same visual analysis described above, analyze all existing building(s) located either on, adjacent to, or regional to the proposed project site, including those with culturally significant building traditions and forms that influence the vicinity's vernacular architectural character. Both narrative and images may be used.

Description of Proposed: Relying on the same visual analysis described above, analyze the proposed building's(s') (or any building additions) architectural context, identifying its architectural character and any regional or cultural building traditions and forms that might be contributing factors. The "Description of Proposed" will typically consist of a narrative description and character sketches (as appropriate).

Building or Site Character Analysis already documented in Historic Structure Reports (HSRs), Cultural Landscape Reports (CLRs), and Design Guidelines may be referenced, but shall be made current with the proposed undertaking.

A brief excerpt from Preservation Brief 17 follows:

Step 1: Identify the Overall Visual Aspects

Identifying the overall visual character of a building is nothing more than looking at its distinguishing physical aspects without focusing on its details. The major contributors to a building's overall character are embodied in the general aspects of its setting; the shape of the building; its roof and roof features, such as chimneys or cupolas; the various projections on the building, such as porches or bay windows; the recesses or voids in a building, such as open galleries, arcades, or recessed balconies; the openings for windows and doorways; and finally the various exterior materials that contribute to the building's character.

Step One involves looking at the building from a distance to understand the character of its site and setting, and it involves walking around the building where that is possible. Some buildings will have one or more sides that are more important than the others because they are more highly visible. This does not mean that the rear of the building is of no value whatever, but it simply means that it is less important to the overall character. On the other hand, the rear may have an interesting back porch or offer a private garden space or some other aspect that may contribute to the visual character. Such a general approach to looking at the building and site will provide a better understanding of its overall character without having to resort to an infinitely long checklist of its possible features and details. Regardless of whether a building is complicated or relatively plain, it is these broad categories that contribute to an understanding of the overall character rather than the specifics of architectural features such as moldings and their profiles.

Step 2: Identify the Visual Character at Close Range

Step Two involves looking at the building at close range or arm's length, where it is possible to see all the surface qualities of the materials, such as their color and texture, or surface evidence of craftsmanship or age. In some instances, the visual character is the result of the juxtaposition of materials that are contrastingly different in their color and texture. The surface qualities of the materials may be important because they impart the very sense of craftsmanship and age that distinguishes historic buildings from other buildings. Furthermore, many of these close up qualities can be easily damaged or obscured by work that affects those surfaces. Examples of this could include painting previously unpainted masonry, rotary disk sanding of smooth wood siding to remove paint, abrasive cleaning of tooled stonework, or repointing reddish mortar joints with gray portland cement.

There is an almost infinite variety of surface materials, textures and finishes that are part of a building's character which are fragile and easily lost.

Step 3: Identify the Visual Character of Interior Spaces, Features and Finishes

Perceiving the character of interior spaces can be somewhat more difficult than dealing with the exterior. In part, this is because so much of the exterior can be seen at one time and it is possible to grasp its essential character rather quickly. To understand the interior character, Step Three says it is necessary to move through the spaces one at a time. While it is not difficult to perceive the character of one individual room, it becomes more difficult to deal with spaces that are interconnected and interrelated. Sometimes, as in office buildings, it is the vestibules or lobbies or corridors that are important to the interior character of the building. With other groups of buildings the visual qualities of the interior are related to the plan of the building, as in a church with its axial plan creating a narrow tunnel-like space which obviously has a different character than an open space like a sports pavilion. Thus the shape of the space may be an essential part of its character.

With some buildings it is possible to perceive that there is a visual linkage in a sequence of spaces, as in a hotel, from the lobby to the grand staircase to the ballroom. Closing off the openings between those spaces would change the character from visually linked spaces to a series of closed spaces. For example, in a house that has a front and back parlor linked with an open archway, the two rooms are perceived together, and this visual relationship is part of the character of the building. To close off the open archway would change the character of such a residence.

The importance of interior features and finishes to the character of the building should not be overlooked. In relatively simple rooms, the primary visual aspects may be in features such as fireplace mantels, lighting fixtures or wooden floors. In some rooms, the absolute plainness is the character-defining aspect of the interior. So-called secondary spaces also may be important in their own way, from the standpoint of history or because of the family activities that occurred in those rooms. Such secondary spaces, while perhaps historically significant, are not usually perceived as important to the visual character of the building. Thus we do not take them into account in the visual understanding of the building.

Building Construction
The construction of sheltered enclosures with walk-in access, for housing persons, machinery, equipment, or supplies. It typically includes all construction of such structures, installation of utilities and equipment (both above and below grade level), as well as incidental grading, utilities and paving, unless there is an established area practice to the contrary. (FAR 22.404-2(c)(1))

Building Gross Square Footage
See Gross Square Footage for Buildings.

A roadway designed exclusively for buses, constructed either at, below, or above grade, and located in a separate right-of-way or within a freeway corridor.


Last updated: November 15, 2016

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