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The City of Portland, Oregon

Portland Bureau of Transportation

Phone: 503-823-5185

Fax: 503-823-7576

1120 SW Fifth Ave, Suite 1331, Portland, OR 97204

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TSDC Definitions of Terms

Definitions of Important Terms

Gross Floor Area (GFA):  The sum (in square feet) of the area of each floor level in the building, including cellars, basements, mezzanines, penthouses, corridors, lobbies, stores and offices, that are within the principal outside faces of exterior walls, not including architectural setbacks or projections. Included are all areas that have floor surfaces with clear standing head room (6 feet, 6 inches minimum) regardless of their use.  If a ground-level area, or part thereof, within the principal outside faces of the exterior walls is not enclosed, this GFA is considered part of the overall square footage of the building.  However, unroofed areas and unenclosed roofed-over spaces, except those contained within the principle outside faces of exterior walls, should be excluded from the area calculations.  For purposes of trip generation and parking generation calculations, the GFA of any parking garages within the building should not be included within the GFA of the entire building.  The unit of measurement for office buildings is currently GFA; however, it may be desirable to also obtain data related to gross rentable area and net rentable area. 

Definitions of Land-use Categories

The following land-use definitions are derived from the ITE Trip Generation (10th Edition) publication.  They have been modified as appropriate for the City of Portland.  ITE land-use codes are shown; where multiple codes are listed, the code used for trip generation is marked with an asterisk (*).  Several categories (Multiple Family, Convenience Market and Administrative Office) have definitions that are derived from the ITE but use trip rates based on observed Person Trip data (survey sites in Portland, California, and Washington, D.C.)  These land use codes are marked with a caret (^).


Single Family, detached:  Includes all single-family detached homes. (ITE # 210) Homes are stratified by size within the fee schedule.  Single family homes (including ADUs) smaller than 1,200 square feet are charged at 50% of the full Single Family rate.

Multi Family: A building designed to house two or more families living independently of each other. Includes low-rise, mid-rise, and high-rise apartments.  (ITE # 220) Also applies to row houses/townhouses/condos. (ITE # 230^)

Senior Housing/Assisted Living/Nursing Home: Residential units similar to apartments or condominiums restricted to senior citizens. (ITE # 252*).  Also includes assisted living facilities (ITE # 253) and nursing homes (ITE # 620).


Bank: A building, with or without a drive-up window, for the custody or exchange of money, and for facilitating the transmission of funds. (ITE # 911*, 912)

Day Care: A facility for the care of infant and preschool age children during the daytime hours.  Generally, includes classrooms, offices, eating areas, and a playground. This also includes preschools. (ITE # 520)

Hotel/Motel: A place of lodging providing sleeping accommodations.  May include restaurants, cocktail lounges, meeting and banquet rooms or convention facilities.  (ITE # 310*, 320)

Service Station/Gasoline Sales: A facility used for the sale of gasoline, oil, and lubricants.  May include areas for servicing or repairing vehicles.  May include a minimart and/or carwash. (ITE # 945)

Movie Theater/Event Hall: Movie theaters consist of audience seating, with one or more screens, and a lobby and refreshment stand.  Typically includes matinee showings. Also applies to event halls that offer entertainment activities.  (ITE # 444)

Carwash: Manual operations where the driver parks and washes the vehicle in a stall, or an automated facility for the same purpose. (ITE # 947)

Health Club/Racquet Club: Privately owned facility that may include swimming pools and whirlpools, saunas, weight-lifting and gymnastics equipment, exercise classes, tennis, racquetball, and handball courts.  May feature exercise sports and other active physical conditioning, as well as a broader range of services such as juice bars and meeting rooms.  (ITE #s 492*, 493)


School, K-12: Covers full range of primary and secondary schools.  Includes elementary, junior high, middle school and high school uses. Both public and private schools are included in this land use. (ITE# 520, 522, 530, average)

University/College/Junior College: Facilities of higher education including two-year, technical, four-year and graduate-level institutions. (ITE # 540, 550, average)

Church: A building providing public worship facilities.  Generally, houses assembly hall or sanctuary, meeting rooms, classrooms, and occasionally dining facilities.  (ITE # 560)

Hospital: A building or buildings designed for the medical, surgical diagnosis, treatment and housing of persons under the care of doctors and nurses.  Rest homes, nursing homes, convalescent homes and clinics are separate uses.  (ITE #610)

Park: Parks are typically owned and operated by the City, but may include private uses.  They can vary widely as to location, type and number of facilities, including recreational centers, boating or swimming facilities, sport fields, playgrounds and picnic facilities.  Fee applies to creation of a developed park from existing undeveloped park land or from newly acquired land.  A developed park includes at least one built amenity that provides a park experience beyond open space.  Land preserved for natural areas, trails and trailheads are not considered developed parks for TSDC purposes. (ITE # 411)


Restaurant (standalone): An eating establishment that sells prepared food or beverages and generally offers accommodations for consuming the food or beverage on the premises.  Usually serves breakfast, lunch, and/or dinner; does not have a drive-up window. Fees apply to standalone restaurants not directly connected to other shopping facilities. (ITE # 931)

Quick Service Restaurant (Drive-through): An eating establishment that offers quick food service and a limited menu of items.  Food is generally served in disposable wrappings or containers, and may be consumed inside or outside the restaurant building.  Restaurants in this category have a drive-up window.  (ITE # 934)


Shopping/Retail: Includes most forms of retail establishments, located in an integrated group of commercial establishments in a shopping center or designated retail area.   Also includes retail space within a mixed-use building.  (This definition does not cover Convenience Markets, Movie Theater/Event Halls or Quick Service Restaurants (Drive-Throughs); these uses will be assessed at their own respective rate.)  For the purpose of this definition a mixed-use building consists of two or more of the following land use categories; residential, shopping/retail, entertainment, hotel/motel, or office.  These land use categories have similar internal trip-making characteristics.  (ITE #820)

Convenience Market: A use that combines retail food sales with fast food or take-out food service, is under 4,000 SF in area, requires a package store liquor license, and is open more than 15 hours per day.  If gasoline sales are included on-site, use Service Station/Gasoline Sales TSDC rate. (ITE # 851^)

Free-Standing Retail Store/Supermarket:  Includes free-standing retail stores, including big-box stores of various types and supermarkets.   Use the Shopping/Retail category for retail stores in a mixed-use building. (ITE # 815)

Car Sales (New/Used): Facilities are generally located as strip development along major arterial streets that already have a preponderance of commercial development.  Generally included are auto services and parts sales along with a sometimes substantial used-car operation.  Some dealerships also include leasing activities and truck sales and servicing. (ITE # 840)


Administrative Office: An administrative office building houses one or more tenants and is the location where affairs of a business, commercial or industrial organization, professional person or firm are conducted.  The building or buildings may be limited to one tenant, either the owner or lessee, or contain a mixture of tenants including professional services, insurance companies, investment brokers, and company headquarters.    (ITE # 710^)

Medical Office/Clinic: A facility that provides diagnoses and outpatient care on a routine basis but does not provide prolonged in-house medical/surgical care.  A medical office is generally operated by either a single private physician/dentist or a group of doctors and/or dentist. (ITE # 720)


Light Industrial/Manufacturing:  A facility that may contain industrial or manufacturing uses.  Manufacturing facilities have the primary activity of converting raw materials or parts into finished products.  In addition to the actual production of goods, manufacturing facilities may also have office, warehouse, research and associated functions. Light Industrial facilities may be characterized by a mix of manufacturing, service and warehouse functions.  Many produce goods by assembling other products, such as assembly of computers or other electronics.  (ITE # 110*, 130)

Warehouse/Storage: Warehouses are primarily devoted to the storage of materials, but may also include limited office and maintenance areas. (ITE # 150)

Self Storage: Buildings in which a number of storage units or vaults are rented for the storage of goods.  Each unit is physically separated from other units, and access is usually provided through an overhead door or other common access point.  (ITE # 151)