Definitions D-G
Demising Wall:
Demising walls that separate tenants from each other and from t public corridors. These partitions require high fireproof ratings, typically run higher than the ceiling height, and often run to the concrete slab of the floor above.
DME:
Distance Measuring Equipment, usually laser-based, suitable for the accurate field measurement of buildings.
Dominant Portion:
A term used differently by various standards to identify the surface of a wall that constitutes the boundary of a floor area for measurement purposes.
Drip Line Method:
A method of measuring Industrial Space defined in the BOMA Industrial Standard as Method B.
Efficiency:
(1) Rental efficiency of a building is its Rentable Area divided by its Gross Area. Rental efficiencies of tall office buildings have typically increased over time. Industrial and retail buildings often have rental efficiencies of 100%, meaning that they are leased using their Gross area.
(2) Planning Efficiency of a building or floor is its Usable Area divided by its Rentable Area, the inverse of the R/U Ratio. Planning efficiencies vary depending on whether a floor is constructed for a single or multiple occupants.
(3) Programming Efficiency is the Assignable Area of a tenant or occupant divided by the Gross area (or Usable or Rentable Area).
Field Dimensions:
Dimensions determined on-site in a building using a measuring tape or LDM. Field dimensions are usually made to apparent building elements and often require adjustment to determine the boundaries of classes of space for the purpose of doing lease area calculations.
Finished Surface:
In the BOMA Standard, it is the surface of a wall, floor or ceiling as prepared for tenant use but excluding the thickness of any special tenant finishes such as paneling or carpeting. Naked studs without gypsum wall board applied are not a finished surface, but concrete or masonry units might be.
Floor Area, Gross:
Section 1002.1 of the International Building Code defines this term as being “The floor area within the inside perimeter of the exterior walls of the building under consideration, exclusive of vent shafts and courts, without deduction for corridors, stairways, closets, the thickness of interior walls, columns or other features. The floor area of a building, or portion thereof, not provided with surrounding exterior walls shall be the usable area under the horizontal projection of the roof or floor above. The gross floor area shall not include shafts with no openings or interior courts.”
Floor Area, Net:
A term used in building codes to describe the actual occupied area of a floor, not including accessory unoccupied areas (stairs, elevator & HVAC shafts, mechanical rooms, etc.)
Floor Area Ratio (FAR):
The floor area of a building expressed as a ratio of the area of the site. Zoning codes often establish a maximum FAR for buildings in certain locations. Some jurisdictions grant bonus FAR in return for certain amenities provided by a building to its neighborhood. For example, a 40% FAR means the equivalent of 40% of the square footage of the land can be built as floor area in a building.
Floor Common Area:
Fully enclosed space on a floor that benefits all occupants of that floor but does not accommodate the tenant’s personnel, furniture, fixtures and equipment. The usual examples are corridors, restrooms, janitor’s closets, electrical closets and HVAC equipment rooms serving only the floor upon which they are located. See individual standards for detailed descriptions.
Floor Plan:
A scaled graphic representation of a horizontal section looking down through a building customarily taken at an elevation of three feet above the finished floor unless noted otherwise. Can be part of the working drawings, record drawings, or space plan, either on paper or in a CAD file.
Floor Plate:
The plan or configuration of a floor within a building.
Floor Rentable Area:
A term used by the BOMA Standards to describe the result of subtracting Major Vertical Penetrations from Gross Measured Area on a floor. This is different than the Rentable Area of the floor, which includes a pro-rata portion of Building Common Area.
Floor Usable Area:
A term used by the BOMA Office Standard connoting the sum of Office, Store and Building Common Areas on a floor.
Furring:
Strips of wood or metal attached to a wall or other surface to provide a fair and even surface for the attachment of surface boards or laths.
Gross Building Area:
The total floor area of the building measuring from the outer surface of the exterior walls and windows and including all vertical penetrations (e.g. elevator shafts, etc) and basement space.
Gross Leasable Area (GLA):
Used in retail leasing. Generally the floor area available for the exclusive use of a retail tenant measured to the outside face of exterior walls and the centerline of demising walls separating tenants. It includes basements and mezzanines.
Gross Living Area (GLA):
A term used by residential appraisers to describe finished, above-grade residential space, measured to the outside face of exterior enclosing walls.
GWCAR Standard:
“The Standard Method of Measurement, A Formula for Calculating Rentable Office and Retail Space”, published by the GWCAR and used only in the District of Columbia and nearby areas of Virginia and Maryland. It is sometimes referred to as the “DC Standard” or the “Washington Standard”.