Stage 1 fire restrictions, enacted for unincorporated areas of western Boulder County.

Assessor’s Glossary

Assessor Glossary




An official reduction or invalidation of an assessed valuation after the initial assessment for ad valorem taxation has been completed.

Abstract of Assessment

Annual report showing the total assessed valuation for Boulder County by the property classification in an abbreviated manner as of a specific date. This data is used by the State Division of Property Taxation to calculate the impact upon the statewide residential assessment rate.


A constructed avenue for vehicles to get from a main road to a building site or parking area (see also “Private Access” and “Driveway”).


A land measure equal to 43,560 square feet.

Active Area

The area a use occupies. This is for purposes of parking calculations.

Actual Value

That value determined by appropriate consideration of the cost approach, the market approach, and the income approach to appraisal.

Ad Valorem Tax

A property tax based on the assessed value of the property, which is not necessarily equivalent to its market value.


Meeting or touching at some point, or across a street, alley or other ROW.

Adjacent Property Owner

An owner of record of any estate, right, or interest in real property which is adjacent to the subject land.

Affordable Housing

Housing which is restricted in sale and/or lease to meet the BOCC’s adopted standards based upon the recommendation and policies of the Boulder County Housing Authority for affordable housing.

Agricultural Products

Products intended for direct human or animal consumption such as vegetables, fruits, dairy products, eggs, grains, meat, poultry, fish, honey, hay, bedding plants and wool.


Uses involving the cultivation of land, production of crops, raising, breeding, and keeping of livestock, and the buying and selling of crops, products or livestock associated with the agricultural operation. Agriculture specifically does not include commercial, institutional, lodging, or recreational uses such as petting zoos, day-care centers, or summer camps.

Airport Hazard

Any structure, object of natural growth, or use of land which obstructs the airspace required for the flight of aircraft in landing or taking off at an airport, or is otherwise hazardous to such landing or takeoff of aircraft.

Airport Protection Surfaces

Imaginary surfaces in an airport vicinity as established by the Federal Aviation Administration Regulation, part 77, ‘Objects Affecting Navigable Airspace,’ U.S. Department of Transportation, FAA, January 1975, as amended, for the purpose of controlling heights of objects in an airport vicinity, as codified under Subchapter E, ‘Airspace,’ of Title 14 of the Code of Federal Regulations, incorporated herein by this reference (Colorado Statute reference Airports, C.R.S. 1973 #41-4-101 et seq.), or by other means accepted by the Board of County Commissioners and as shown on the Airport Protection Surface maps adopted and incorporated into this Resolution for purposes of regulating the height of structures.


A tangible or intangible benefit of real property that enhances its attractiveness or increases the satisfaction of the user, but is not essential to its use. Natural amenities may include a pleasant location near water or a scenic view of the surrounding area; man-made amenities include swimming pools, tennis courts, community buildings, and other recreational facilities.

Animal Unit

A term used to establish an equivalent density for various species of livestock. Young animals shall not be counted until they are weaned. Horses include mules and donkeys.


An analysis, opinion, or conclusion relating to the nature, quality, value, or utility of specified interests in, or aspects of, identified real estate.

Approaches to Value

Systematic procedures used to derive value indications in real property appraisal. (See also cost approach, income capitalization approach, sales comparison approach.)


The visible, functional, or ornamental objects accessory to and part of a building.


A process in which one or more individuals are selected by opposing parties to settle a dispute outside of court. The decision of an arbitrator is generally binding.

Arm’s-length Transaction

A transaction between unrelated parties under no duress.

Asbuilt Profile

A map or drawing which depicts a vertical section of a road, street, curb, conduit, or other physical feature as it has been actually constructed.

Aspect (a.k.a. exposure)

The primary direction a slope faces (N, S, E, W, or some combination).


To estimate property value as a basis for taxation.

Assessed Value

The value of a property according to the tax rolls in ad valorem taxation. May be higher or lower than market value, or based on an assessment ratio that is a percentage of market value.


The official valuation of property for ad valorem taxation.

Assessment Period

The period during which all property in the assessment district must be reassessed; also called “assessment cycle” or “assessment frequency.”

Assessment Ratio

The relationship between assessed value and market value.

Assessment Roll

A public record that shows how the property tax levy is allocated among the property owners in a jurisdiction with taxing powers; usually identifies each taxable parcel in the jurisdiction, the name of the owner of record, the address of the parcel or the owner, the assessed value of the land the assessed value of the improvement(s), applicable exemption codes if any, and the total assessed value.

Assessment/Sales Ratio

The number derived by dividing the assessed value by the selling price; used as a measure of the relationship between a property assessment and market value. `


The head of an assessment jurisdiction. Assessors are elected in Colorado except in Denver and Broomfield. The term is sometimes used collectively to refer to all administrators of the assessment function. One who discovers, lists, and values real property for ad valorem taxation.

Assumptions and Limiting Conditions

For appraisal and analysis purposes, a list of assumptions and limitations on which an appraisal or analysis is based.

Average Daily Trips (ADT)

The average 24-hour volume, of all lanes in both directions being further defined as the total number during a stated period, divided by the number of days in that period. Unless otherwise stated, the period is a year. The term is commonly abbreviated as ADT.



Single microorganisms that are found in every environment on earth. While most bacteria are rendered harmless by human immune systems some can cause disease (Pathogenic)

Bargain and Sale Deed

A deed that conveys real property from a seller to a buyer but does not guarantee clear title; used by court officials and fiduciaries to convey property they hold by force of law, but to which they do not hold title. (See also deed, quitclaim deed, warranty deed.)

Base Flood

A flood having a one percent chance of being equaled or exceeded in any given year. The term is used interchangeably with intermediate regional flood, one hundred year flood, and one percent chance flood.


Area fully or partially below ground level

Basement Finished

See: Finished Basement


Boulder County Public Health


Solid rock underlying surface materials.

Best Management Practices (BMPs)

Schedules of activities, prohibitions of practices, general good housekeeping practices, pollution prevention and educational practices, maintenance procedures, and other management practices to prevent or reduce the discharge of pollutants

directly or indirectly to stormwater, receiving waters, or stormwater conveyance systems. BMPs also include treatment practices, operating procedures, and practices to control site runoff, spillage or leaks, sludge or water disposal, and drainage from raw materials storage.


The portion of the wastewater stream that originates from toilet fixtures


A designated portion of subdivided land which, unless otherwise indicated on the plat, is land intended for future development in accordance with the applicable Subdivision Regulations.

Board of Equalization

A non-judicial board that reviews assessments to see that all districts are assessed at a uniform level of value; authorized to raise or lower the assessments to achieve a uniform basis of taxation.


The main stem (trunk) of a tree.


A bond is set according to a Judge; Court ordered warrant or a Bond Commissioner. The purpose of the bond is to assure an individuals appearance in court. The amount of the bond is what it will take to release an individual from jail.

Bond Commissioner

Are agents of the court that, in some cases, may set Bonds for new arrestees before they appear in front of a judge.

Book and Release

The arresting officer can make a determination that the defendant can be released after they are booked. This usually occurs with misdemeanor offenders; however, can be done with some felonies.

Boulder County Comprehensive Plan

That document, including all amendments, adopted by the Planning Commission, which provides policy direction to the County and the public about how existing and proposed land uses ought to be evaluated, how the various governmental and land management entities in the County should coordinate their activities, and how environmental resources should be preserved. The Boulder Valley Comprehensive Plan and any similar subarea plans are considered part of the Boulder County Comprehensive Plan.

Breakdown Method

A method of estimating accrued depreciation in which the total loss in the value of a property is estimated by analyzing and measuring each cause of depreciation (physical, functional, and external) separately.

Bridge Safety Surcharge

Provides for “Funding Advancement For Surface Transportation and Economic Recovery” as described in Senate Bill 09-108. This surcharge shall be imposed on any registration made on or after July 1, 2009.


Any permanent structure built for the support or shelter of any use or occupancy.

Building Footprint

The outline of the total area which is covered by a building’s perimeter at ground level.

Building Height (Structure Height)

The vertical distance from any part of the structure, excluding appurtenances, to the existing or natural grade below. In a platted subdivision for which overlot grading was permitted prior to October 18, 1994, the overlot grading shall be the existing grade.

Building Lot

A parcel occupied by, or designated by the Director pursuant to the Boulder County Land Use Code to be occupied by, a use which is required by the Zoning District provisions of the Boulder County Land Use Code to comply with the minimum lot area requirements of the zoning district in which it is located. Except as provided in subsection (A) below, the parcel shall be of sufficient size and shape to conform to all requirements of the zoning district within which it is located.

A. A substandard parcel shall be considered a building lot only if it meets one of the following criteria:

1. A parcel upon which a use, which is required to comply with the minimum lot area requirements of the zoning district in which it is located, lawfully exists or, if none exists, has lawfully existed prior to the effective date of the Boulder County Land Use Code.

2. A parcel which the Board of County Commissioners has exempted from the definition of ‘subdivision’ with the specific intent, as stated in the exemption Resolution, of allowing the parcel to be designated as a building lot; provided however that said parcel shall remain subject to any use and building requirements imposed pursuant to Article 9 as well as all other provisions and requirements of this Code.

3. A lot, tract, undivided block, or other plot of land, other than an outlot or right-of-way, within an area of subdivided land, which met the lot area and lot frontage requirements of this Code in effect at the time of the approval of the subdivided land, such land shall be designated as a building lot in accordance with those area and/or frontage requirements in effect at the time of its approval, subject, however, to all other provisions and requirements of the Boulder County Land Use Code, as amended.

4. A parcel which conformed to the lot area and lot frontage requirements of the zoning district in which it was located at the time it was created, and which has continued to be held as a separate parcel, shall be designated a building lot in accordance with those area and frontage requirements in effect at the time of its creation, and with all other provisions and requirements of the Boulder County Land Use Code, as amended; provided, however, if such parcel was at any time owned by a governmental entity, it may be occupied only in accordance with the area and frontage requirements in effect at the time legal title was transferred from the governmental entity to a person, and with all other provisions and requirements of this Code, as amended.

B. For any merger of parcels of land or lots under the provisions of the Boulder County Land Use Code, which merger is not requested in writing by each owner of an affected parcel, and which merger occurs for the first time on or after October 1, 2003 (the effective date of Senate Bill 03-067 as codified in C.R.S. Section 30-28-139), the following provisions shall govern, as expressly required in C.R.S. Section 30-28-139:

1. Prior to the completion of the merger, the County shall send notice of the County’s intent to complete the merger to each owner of the affected parcels by certified mail, at the address shown on the records of the County Assessor. The notice shall also specify that each such owner may request a hearing on the proposed merger pursuant to Subsection 2., immediately below, and shall specify action to be taken by such owner to request such hearing, including, without limitation, the requirement that said owner shall request the hearing no later than 120 days after the date on which the owner receives the notice.

2. Prior to the completion of the merger, where each owner of an affected parcel has timely requested a hearing on the proposed merger satisfying the requirements of Subsection 1., immediately above, a public hearing on said merger shall be held before the Board of County Commissioners. The hearing shall be conducted for the purpose of allowing the Board to discuss with the owner of each affected parcels the Board’s reasons for proceeding with the merger, and to give each owner the opportunity to submit any basis provided under law for challenging the merger. In the case of a timely hearing request, the County shall provide notice of the time, place, and manner of the hearing to each owner of the affected parcels and shall also publish the notice in a newspaper of general circulation in the County in a manner sufficient to notify the public of the time, place, and nature of said hearing. In order to give each such owner of an affected parcel the opportunity to take whatever remedial action is allowed under the law prior to the hearing before the Board, the County shall not hold the hearing any sooner than 90 days after the date on which the owner received the County’s initial mailed notice as provided in Subsection 1, above.

3. Where the owner of each affected parcel fails to timely request a hearing on the proposed merger satisfying the requirements of Subsection 1., above, no such hearing is required, and the affected parcels shall be merged in accordance with the requirements of this Subsection C.

4. No merger of parcels that is the subject of a hearing pursuant to Subsections 1. and 2., above, shall be effective unless:

a. The owner of the parcels has given his, her, or its consent to the merger of said parcels; and

b. The merger has been approved by a majority of the Board of County Commissioners.

5. Nothing in this Subsection C. shall be construed to abrogate or otherwise diminish or expand any rights a landowner may have under Article 68 of Title 24, C.R.S., pertaining to vested property rights.


The total volume of the structure, found by multiplying the square footage by the height.

Bundle of Rights Theory

The concept that compares property ownership to a bundle of sticks with each stick representing a distinct and separate right of the property owner, e.g., the right to use real estate, to sell it, to lease it, to give it away, or to choose to exercise all or none of these rights.


Camper Trailer

A wheeled vehicle without motive power which is designed to be drawn by a motor vehicle over the public highways and which is generally and commonly used for temporary living or sleeping accommodations.


The cover formed collectively by the crowns of adjoining trees.

Canopy Closure – (See also Crown Spacing)

The distance between the treetops if one were to look straight up. If the canopy closure is very dense, then the crown spacing is very tight with very little sunlight able to pass through. This is typical for mixed conifer or lodgepole pine forests. Compare to an open canopy for ponderosa pine.

Cash Bond

A cash amount is paid by the defendant to cover the total cost of the bond. This can be paid in the form of cash, a money order, a credit card or bank checks. Personal checks are not accepted. There is an attached fee to post a cash bond.

Certificate of Occupancy

A certificate issued by the County after final inspection and upon a finding that the building, structure, or development complies with all provisions of the applicable county codes, permits, requirements and approved plans.

Certificate of Title

A document, usually given to a home buyer with the deed, which states that the title to the property is believed to be clear; usually prepared by an attorney or another qualified person who has examined the abstract of title for the property.


A reservoir (as an underground tank) usually for the purposes of storing water (as for domestic or fire water storage). Fire cisterns generally range from 1,500 to 5,000 gallons (individual) to 10,000 to 30,000 gallons (community) capacity. Individual cisterns are usually made of concrete; community cisterns are of steel or fiberglass. Some draft plumbing is generally required to facilitate moving water out of the tank (see Dry Hydrant).

Class Construction

The classification of buildings according to the fire-resistance of the materials from which they are constructed, e.g., structural steel framing (Class A), reinforced concrete framing (Class B), masonry walls (Class C), wood or light steel framing (Class D).

Clean Water Act

The Federal Water Pollution Control Act (33 U.S.C. § 1251 et seq.) as amended.

Clearing and Grubbing

Any activity that removes the surface cover to expose bare ground.

Common Open Space

A parcel of land, an area of water, or a combination of land and water within a site designed and intended primarily for the use or enjoyment of residents, occupants, and owners within that development.

Community Service Area (CSA)

A. Municipal CSA – A boundary line drawn around a municipality within which a city expects to accommodate future urban growth. Community Service Area plans provide, when jointly adopted by both municipal and county governments, a mutually binding comprehensive plan for county lands adjacent to each municipality. It is expected that land within municipal Community Service Areas will be developed in an urban pattern, urban services will be provided by the municipalities, and the area will eventually be annexed. The following are terms used by the various Plains municipalities that fit with the Community Service Area definition, and each area has been mapped.

Boulder — Boulder Service Area (Area I and II of the Boulder Valley Comprehensive Plan);

Broomfield – Southeast Boulder County Area Comprehensive Development Plan Intergovernmental Agreement or IGA, and the areas described within the southeast Boulder County, South 96th Street, Dillon Road and U.S. 287 Area Comprehensive Development Plan IGA (commonly referred to as the Northwest Parkway IGA);

Erie – Influence Area (East Central Boulder County Comprehensive Development Plan IGA;

Lafayette – Influence Area (East Central Boulder County Comprehensive Development Plan IGA;

Longmont – Longmont Planning Area or LPA (Longmont Planning Area Comprehensive Development Plan IGA);

Louisville – Influence Zone (Lafayette/Louisville Buffer Comprehensive Development Plan IGA) and areas described within the Northwest Parkway IGA;

Lyons – Potential Service Area (Docket BCCP-86-01), Lyons Comprehensive Plan adopted by Boulder County on April 5, 1988): and,

Superior – Influence and Study Areas (Superior Area Comprehensive Development Plan IGA).

B. Limited CSA — A boundary line drawn around an unincorporated area as designated in the Boulder County Comprehensive Plan within which it is expected that land may be developed and provided with a limited range of urban services, including:

Niwot — an adopted Community Service Area (Niwot, Lefthand, Boulder Creek Subregion Goals, Policies and Maps Element, Boulder County Comprehensive Plan.)


A shortened term for similar property sales, rentals, or operating expenses used for comparison in the valuation process; also called “comps.”


In real estate, a group of buildings, site improvements, and support facilities designed to carry out related activities in a single location; e.g., apartment complex, office complex.


A form of fee ownership of separate units or portions of multi-unit buildings that provides for formal filing and recording of a divided interest in real property.

Condominium Ownership

A building, or group of buildings, in which dwelling units, offices, or floor area are owned individually, and the structure, common areas, and facilities are owned by all the owners on an undivided basis.

Conifer (Cone-bearing)

Plants that have “naked seeds” (gymnosperm), generally borne on woody cones. Such trees also have needles or scale-like leaves, and are usually evergreen.

Conservation Easement

The grant of a property right stipulating that the described land will remain in a certain state and precluding future or additional development.

Construction Activity

Any activity which disturbs the earth surface or is related to the erection or modification of structures including but not limited to clearing and grubbing, grading, excavating, construction and demolition.

Construction Plan

The maps or drawings accompanying an application which show the specific location and design specifications of improvements to be installed in accordance with the requirements of approval by the Planning Commission and Board of County Commissioners.


A. Touching along a common boundary for at least 15 feet.

B. The contiguity of land areas shall not be affected by the existence between them of a road or alley; a public or private right-of-way; a public or private transportation or utility right-of-way; a river, creek, stream, or other natural or artificial waterway; or an intersecting mining claim.

C. The contiguity of land areas shall be assumed to be disrupted by the existence of a freeway, expressway, principal arterial, and minor arterial, and by lands contained within the legal boundaries of any municipality.

Correction Plat

A rerecording of a previously approved plat which is intended to correct a technical error in the plat.

Co-Signed Personal Recognizance Bond

A dollar amount of the bond is established, however a person other than the defendant has to sign the bond promising that the defendant will appear for their future court dates. The “co-signer” must be approved through the courts or Bond Commissioners. The “co-signer” is also responsible for paying the cash amount of the bond in the event that the defendant fails to appear in court.

Cost Approach

A set of procedures through which a value indication is derived for the fee simple interest in a property by estimating the current cost to construct a reproduction of, or replacement for the existing structure; deducting accrued depreciation from the reproduction or replacement cost; and adding the estimated land value plus an entrepreneurial profit. Adjustments may then be made to the indicated fee simple value of the subject property to reflect the value of the property interest being appraised.


The largest division of local government in all states except Louisiana and Alaska, where the comparable units are parish and borough, respectively.

Covered Porch

Covered areas that are attached to the principal structure. Covered porch may not be enclosed with solid walls, glass, or screens.

Critical Fire Weather

A set of weather conditions (usually a combination of low relative humidity and wind) whose effects on fire behavior make control difficult and threaten firefighter safety.


The collective branches and foliage of a tree.

Crown Fire

Wildfire spreading through the crowns of trees, encompassing whole stands as opposed to a few individuals (see torching).

Crown Spacing

The distance from the edge of one tree canopy to another. Crown spacing varies from open (with 10 feet or more of space between tree canopies) to closed (where trees may be growing in very close proximity with little space between them).

Curable Depreciation

Items of physical deterioration or functional obsolescence that are economically feasible to cure. Economic feasibility is indicated if the cost to cure is equal to or less than the anticipated increase in the value of the property.

CWT (Hundred weight)

Using the empty weight, round up to the nearest hundred pounds and drop the last two zeroes. Example: Empty weight 4,726 pounds = 48 CWT. Title Complete Notices generated when the application for title has been processed indicates the CWT. Selling dealers can provide you the empty weight.



Perennial plants that normally shed all of their leaves for part of the year (usually during winter). Leaves on these plants are generally wide (broadleaf), as opposed to needle-like, and may have simple or complex margins or forms (such as compound leaves). Seeds are generally encased in a fruit (angiosperm).


A legal document conveying ownership of real property recorded in the real property records of the Boulder County Clerk and Recorder.


A written, legal instrument that conveys an estate or interest in real property when it is executed and delivered. (See also Bargain & Sale Deed, Quitclaim Deed, Warranty Deed.)

Defensible Space

A designated area (either natural or man-made) around a home or other structure where fire suppression operations can safely occur. This is an area where material capable of allowing the spread of wildfire has been treated, cleared of vegetation, or otherwise modified to slow the rate of spread and intensity of a wildfire. It is intentionally created and maintained so as to be free of any features that would tend to increase the risk of damage from wildfire.


In appraising, a loss in property value from any cause; the difference between the reproduction or replacement cost of an improvement on the effective date of the appraisal and the market value of the improvement on the same date. In regard to improvements, depreciation encompasses both deterioration and obsolescence.

Design Water Table

The elevation of the water table at the location of the proposed building site either (a) as measured between May 1 and July 15 in any year; or (b) the predicted May 1 July 15 elevation of the water table where the prediction is based on a comprehensive geohydrologic study directed by a professional engineer.


Impairment of condition; a cause of depreciation that reflects the loss in value due to wear and tear, disintegration, use in service, and the action of the elements.

Development Agreement

The agreement between the owner and county which specifies the terms and conditions of the approval. This agreement implements the site specific development plan which establishes vested rights under Article 68 of Title 24, C.R.S.

Development Report

A report which addresses issues and reports facts concerning activities, utilities, circulation and traffic, surrounding land uses, community facilities, environment, and other factors for a given development proposal.

Diameter at Breast Height (DBH)

The common height at which the diameter of a tree is measured. Equal to four and half feet (4.5’) from the base of the tree.

Directly Visible (Outdoor Lighting)

Allowing a direct line-of-sight to the light source or lamp.


A contract of sale resulting in the transfer of equitable title to an interest in subdivided land; an option to purchase an interest in subdivided land; a lease or an assignment of an interest in subdivided land; or any conveyance of an interest in subdivided land which is not made pursuant to one of the foregoing. (C.R.S 30-28-101(1))

Disturbed Area

That area of the land’s surface that is subject to or in any way changed by construction activity.


A vehicular ingress/egress route for residents and emergency service personnel, serving no more than two buildings or structures (compare to Private Access).

Dry Hydrant

A non-pressurized pipe system, permanently installed in an existing body of water (such as a cistern, lake, pond, or stream), which provides a means of suction to supply water to a fire engine or tender. The dry hydrant system gives fire apparatus easy access to these water sources and limits the amount of time needed to create the draft necessary to fill water tanks and charge hose lines.


A layer of accumulated dead organic matter (such as pine needles, leaves, and dried grass) that would carry a surface fire. Also contributes to ground fuel accumulation, smoldering and creeping fires.


A. A building or portion thereof used exclusively for residential occupancy, including one-family dwellings and multiple-family dwellings, but not including hotels, motels, tents, seasonal vacation cabins, camper trailers, or other structures designed or used primarily for temporary occupancy.

B. A dwelling shall also include the following types of residential buildings which are factory made and not constructed on site:

Manufactured homes which are not less than 24 feet in width and 35 feet in length, which are installed on an engineered permanent foundation in accordance with all applicable County requirements, and which have a brick, wood, or cosmetically equivalent exterior siding and a pitched roof, pursuant to C.R.S. 30-28-115(3)(a), as amended; and

Factory built modular housing which is certified by the State of Colorado to meet Uniform Building Code requirements pursuant to the Colorado Housing Act of 1970, C.R.S. 24-32-701, et seq., as amended.

Dwelling Unit

One or more rooms designed to accommodate one family and containing only one kitchen plus living, sanitary, and sleeping facilities.


Earth Material

Any mineral, rock, natural soil, overburden, or fill, or combination of such materials.


A right granted by a property owner permitting a designated part or interest of the property to be used by others for a specific use or purpose.


An interest in real property that conveys use, but not ownership, of a portion of an owner’s property. Access or right-of-way easements may be acquired by private parties or public utilities. Governments dedicate conservation, open space, and preservation easements.

Economic Area

Groups of neighborhoods within the county that have similar trends in the market. For example, sales and resales within an economic area will reflect similar influences, such as areas with higher foreclosure activity or areas where the market has remained stable. In Boulder County, we use economic areas in establishing market trends for mass appraisal purposes.


A way out; an exit or outlet.

Electric Substation

An assemblage of equipment and appurtenant facilities designed for voltage transformation, or voltage control of electricity in amounts of 115,000 volts or more.

Electric Transmission Line

A series of three or more structures and appurtenant facilities erected above ground, supporting one or more conductors emanating from a power plant or a substation, designed to transmit electric energy in voltages of 115,000 volts or more.

Electrical Distribution Line

Structures and appurtenant facilities used for the distribution of electric energy in voltages less than 115,000 volts.

Emergency Route

A designated route for use in an emergency. May be used routinely, but under emergency conditions becomes the designated route for mass movement of material and personnel as well as for evacuations.

Eminent Domain

The right of government to take private property for public use upon the payment of just compensation. The Fifth Amendment of the U.S. Constitution, also known as “the takings clause,” guarantees payment of just compensation upon appropriation of private property.


The process by which an appropriate governmental body attempts to ensure that all property under its jurisdiction is assessed equitably at market value or at ratio or ratios as required by law.

Equestrian Arena

An improved area, generally fenced, of at least 30 feet in width or length within which equestrian activities involving horse riding or driving occurs.

Escape Route

An egress route specifically for the use of evacuation during an emergency.


The right of government that gives the state titular ownership of a property when its owner dies without a will or any ascertainable heirs.


Inventories for resale, property rented for 30 days or less, materials and supplies consumed; livestock, and all personal property schedules with an actual value of $4,000 or less are exempt from property taxation by law.

Exemption Plat

An amendment or change to a plat which is exempt from the requirements of Article 5 of the Boulder County Land Use Code (Subdivision Regulations), and which falls within the scope of and must instead meet the requirements of Sections 9-200 through 9-202 of the Boulder County Land Use Code. Exemption plats for certain subdivisions with a sketch plan approved prior to March 22, 1978, which affect significant natural resources, are separately addressed under Article 4-300 of the Boulder County Land Use Code.

Existing Manufactured Home Park

Manufactured home park for which the construction of facilities including utilities, final grading, or pouring of pads and the construction of streets is completed before the effective date of the Boulder County Land Use Code Article 4, Section 4-400, Floodplain Overlay District.

Expansive Soil

Rock or soil that shrinks or expands excessively with changes in moisture content.


The removal of any earth materials from places of natural occurrence to surface location. ‘Extraction’ shall not include ‘prospecting’ activities involved in the act of searching for or investigating a mineral deposit as defined under the State Mined Land Reclamation Act. However, it shall include activities involved in the development of a mineral deposit once found as defined under the State Mined Land Reclamation Act, including but not necessarily limited to preparing the site for mining, defining further the mineral deposit by drilling or other means, conducting pilot plant operations, and constructing roads and other facilities accessory to mining (See 34-32-103, C.R.S., as amended.)



A structure or place which is built, installed, or established to serve a particular purpose.


A. An individual, or two or more individuals related by blood, marriage, or adoption, and not more than two roomers or boarders; or

B. Two adults and any of their lineal descendants; or

C. A group of not more than three unrelated individuals; and who are living together as a single housekeeping unit.


A parcel of land used for agricultural purposes: to produce agricultural products that originate from the land’s productivity for the primary use of obtaining a monetary profit; i.e., crops have been raised, harvested, and or sold.

Fee Appraiser

An appraiser who is paid a fee for the appraisal assignments he or she performs.


A deposit of earth material placed by artificial means.

Final Plat

A map of land proposed to become subdivided land, and specified supporting materials, whose purpose is to allow evaluation of the detailed layout and design for the development, including but not necessarily limited to the final engineering plans, subdivision development agreement, letters of credit, conservation easements, homeowners covenants as may be applicable to the terms of the development’s approval, any outstanding design issues such as building heights or envelopes and landscaping, and the plat as proposed for recording. The final plat is the last of the three required steps (sketch plan, preliminary plan, and final plat) for obtaining approval of subdivided land, and must be consistent with the approved sketch plan and preliminary plan.

Final Value Estimate

The range of values or single dollar figure derived from the reconciliation of value indications and stated in the appraisal report.

Finished Basement / Basement Finished

Any basement area that has ANY THREE of the following: ceiling tile, interior doors, stud walls, drywall, paneling, finished lighting fixtures, bathroom, resilient flooring, carpet, individual wiring

Fire Access

An access specifically (possibly exclusively) for the use of emergency vehicles. Used during a fire event to gain access to an otherwise inaccessible area or one that is generally closed to vehicular traffic (such as a wilderness area).

Fire Area

The floor area of a structure used to determine the adequate water supply (fire flow) for fire suppression.

Fire Resistant Materials

Construction materials designed to resist the spread of fire. For detailed descriptions see the Uniform Building Code

Fire Weather

Weather conditions favorable to the ignition and rapid spread of fire. In wildfires, this generally includes high temperatures combined with strong winds and low humidity (see also Critical Fire Weather).

Fish Farm

The hatching and raising of fish for the purpose of harvesting and sale. Fish farms are exclusive of recreational fishing operations.


Items that were once movable chattels but have become physically incorporated in a building or affixed to land.

Flood Insurance Rate Map (FIRM)

An official map of the Federal Emergency Management Agency (FEMA), on which the area subject to flooding by the base flood has been delineated either by approximate or detailed engineering study. These maps also delineate flood insurance rate zones and may include the delineation of water surface elevations and floodway boundaries.

Flood Insurance Study

The official report provided by the Federal Emergency Management Agency (FEMA) that includes flood profiles, the Flood Boundary Floodway Map, and the water surface elevation of the base flood.

Flood or Flooding

A general and temporary condition of partial or complete inundation of normally dry land areas from either the overflow of watercourses, or the unusual and rapid accumulation or runoff of surface waters from any source.

Flood Plain

The flat surfaces along the courses of rivers, streams, and other bodies of water that are subject to overflow and flooding.

Flood Profile

A graph showing the flood water surface elevations and the elevations of the underlying land as a function of distance along a path of flow.

Flood Protection Elevation

An elevation two feet above the water surface elevation of the base flood. The two foot freeboard is a factor of safety, attempting to compensate for the many unknown factors that could contribute to flood heights greater than the height calculated for a selected size flood and floodway conditions, such as wave action, bridge and culvert openings, and the hydrological effect of urbanization of the watershed.


Those portions of the Floodplain Overlay District that are not in the floodway.


Areas that are inundated by the base flood.

Floodplain Development

Under floodplain regulations, any public or private construction or activity that changes the basic character or the topography of the land on which the construction or activity occurs, including but not limited to any manmade change to improved or unimproved real estate, construction or substantial improvement of buildings or other structures. Development includes mining, dredging, filling, grading, paving, excavation, or drilling operations; and all dams, reservoirs, walls, embankments, berms, levees, dikes, piles, abutments, projections, channel rectification, roads, bridges, culverts, excavations, and fills.

Floodplain Encroachment

Any development, stockpile, refuse, or matter in, along, across, or projecting into any floodplain which might impede, retard, or change the direction of a flow of water, either by itself or by catching or collecting debris carried by such water. The term floodplain encroachment shall not include any device or structure reasonably necessary for flood control or prevention.


A combination of provisions, changes, or adjustments to structures, moveable objects, or properties for the purpose of the reduction or elimination of the potential for flood damage from the base flood.


A. Those portions of the Floodplain Overlay District required for the passage or conveyance of the base flood in which waters will flow at significant depths or with significant velocities. It includes the channel of a river or creek and any adjacent floodplain areas that must be kept free of development and other encroachments so the base flood can be conveyed without substantial increase in flood height.

B. Specifically, the floodway is defined according to the following criteria:

Those areas defined by the effective Flood Insurance Rate Map with cross-hatching overlay of areas in Zone AE;

Those portions of the Floodplain Overlay District that must be kept free of development and other encroachments so the base flood is conveyed with no more than a one foot increase in the water surface elevations, and which areas have been identified as floodway by the Colorado Water Conservation Board within those reports (including technical addendum thereto) listed in Section 4-402 of this Code;

Where the floodway has not been so identified, it is those portions of the Floodplain Overlay District determined to be in the floodway by a detailed hydraulic analysis approved by the County Engineer as set forth in Section 4-407(B)(7) of this Code;

Where the floodway has not been so identified or determined, it is those portions of the Floodplain Overlay District where floodwater from the base flood is 18 inches or greater in depth.

C. However, in no instance shall the floodway extend less than 25 feet from the banks of the river or creek, unless such bank consists of an impervious natural rock wall or cliff which is higher than the flood elevation.

Floor Area

The area of a building or structure, existing or new, including basements and attached garages calculated without deduction for corridors, stairways, closets, the thickness of interior walls, columns, or other features as measured from the exterior face of the exterior walls. Floor area does not include the area of any covered porch. (For Residential Structures, see also the Boulder County Land Use Code Article 18-189D.)

A. Above Grade Floor Area Any floor area in which the floor is higher than existing grade, plus a portion of basement floor area in cases where any part of the basement story is higher than existing grade. The first two vertical feet of any basement story that are exposed above existing grade are excluded from the above grade floor area calculation. The above grade portion of the basement floor area is calculated by multiplying the total basement floor area by the percentage of the volume of the basement story that is higher than existing grade.

1. If the finished floor surface of the main story of a residence is partially or completely above finished grade, then all floor area in the main story will be considered above grade floor area. All floor area in any stories above the main story will also be considered above grade floor area. The main story is defined as the story that includes, but is not limited to the kitchen, dining room, and living room.

B. Below Grade Floor Area Excepting the portion that is defined as above grade floor area, a portion of the basement floor area in which all or part of the floor is below existing grade. The first two vertical feet of any basement story that are exposed above existing grade are included in the below grade floor area calculation. Below grade floor area is calculated by multiplying the total floor area of the basement by the percentage of the volume of the basement that is below existing grade.

Forced Sale

Offering and transferring property for a valuable consideration under conditions of compulsion.


The legal process in which a mortgagee forces the sale of a property to recover all or part of a loan on which the mortgagor has defaulted.


Any biological material (vegetation), living or dead, which contributes to wildfire spread. Fuels are classified into medium, light and heavy, and correspond to the various fuel models:

Light fuels

consist of grasses, herbaceous plants, and round wood (stems) less than 0.25 inches (6.4 mm) in diameter (See Fuel Models A, C, E, L, N, P, R, and S).

Medium fuels

consist of round wood (stems) 0.25 to 3 inches (6.4 mm to 76 mm) in diameter. See Fuel Models B, D, F H, O, Q and T).

Heavy fuels

consisting of round wood (stems) 3 to 8 inches (76 to 203 mm) in diameter (see Fuel Modes G, I J, K and U).


Gas/Other means all fuel types except diesel.

Fuel Break

An area where native vegetation has been permanently modified or replaced so that fire burning into it can be more easily controlled. Generally this involves removing selected trees and shrubs from an area to break up fuel continuity. Fuel breaks are strategically located for fighting anticipated wildfires. Breaks also divide fire-prone areas into smaller areas that provide easier fire control and to provide access for firefighting.

Fuel Continuity

The proximity of fuels to each other. This measure helps in determine if a fire can sustain itself and grow.

Fuel Loading

The oven-dry weight of fuels in a given area, usually expressed in pounds per acre (lbs/ac). Fuel loading may be referenced to fuel size or time lag categories, and may include surface fuels or total fuels.

Fuel Model

A lettering or numbering system that identifies the types and quantity of fuels found in an area that directly influence fire behavior. Models generally range from light to heavy and roughly correspond to potential increase in fire behavior and intensity.

Fully Shielded Light Fixture

A lighting fixture constructed in such a manner that all light emitted by the fixture, either directly from the lamp or a diffusing element, or indirectly by reflection or refraction from any part of the luminaire, is projected below the horizontal as determined by photometric test or certified by the manufacturer. Any structural part of the light fixture providing this shielding must be permanently affixed.


Gas Distribution Pipeline

Mains, services, equipment and appurtenant facilities which carry or control the supply of gas from the point of local supply to and including the sales meter.

Gas Regulator Station

An assemblage of equipment which reduces, regulates and meters natural gas pressure in the transmission line, holder, main, pressure vessel or the compressor station piping. This may include auxiliary equipment such as valves, control instruments or control lines as well as piping.

Gas Transmission Pipeline

Pipelines and appurtenant facilities installed for the purpose of transmitting gas from a source to a distributing center, to a large volume customer, or to interconnect sources of supply.

Geologic Hazard

A geologic condition which may pose a significant threat to persons or property.


The sensation produced by a bright source within the visual field that is sufficiently brighter than the level to which the eyes are adapted to cause annoyance, discomfort, or loss in visual performance and visibility; blinding light. The magnitude of glare depends on such factors as the size, position, brightness of the source, and on the brightness level to which the eyes are adapted.


Any excavating, filling or combination thereof. Grading is regulated by the appendix chapter titled “Excavation And Grading,” of the most current edition of the Uniform Building Code, as published by the International Conference of Building Officials, 5360 Workman Mill Road, Whittier, California 90601, with the administration of the excavation and grading provisions otherwise being in accordance with the administrative provisions of the current edition of the Boulder County Building Code.


A person to whom property is transferred by deed or to whom property rights are granted by a trust instrument or other document.


A person who transfers property by deed or grants property rights through a trust instrument or other document.


To feed on growing herbage; to crop and eat in the field: to feed on herbage.

Ground Fire

A fire that occurs sub-surface (underground) in the duff, litter or roots.

Guaranteed Title

A title whose validity is insured by an abstract, title, or indemnity company.



A source of danger or a chance event; something that creates risk.

Hazard Tree

A tree that is weakened in some way (such as by wind, fire, or disease) such that it represents a hazard to specific target (such as a home or roadway) if it were to fail and fall.

Heavy Timber

A solid wood member with at least 6″ nominal thickness.

Highest and Best Use

The reasonable, probable, and legal use of vacant land or an improved property, which is physically possible, appropriately supported, financially feasible, and that results in the highest value. The four criteria the highest and best use must meet are legal permissibility, physical possibility, financial feasibility, and maximum profitability.


Having to do with the growing of fruits, vegetables, flowers, or ornamental plants.



International Association of Assessing Officers.

Ignition Resistant (IR) Construction

Building with materials that are inherently non-combustible or that don’t readily contribute to fire spread. Also a schedule of additional requirements for construction in WUI areas base on the wildfire hazard of a particular site. These requirements may be broken down into three categories, (IR-1, IR-2, IR-3) corresponding to the specific wildfire hazard of a site (Extreme, High, Moderate).


The amount of light falling onto a unit area of surface (luminous flux per unit area) – measured in lumens per square meter (lux) or lumens per square foot (footcandles).

Improved Land

Land that has been developed for some use by the construction of improvements; also land that has been prepared for development by grading, draining, installing utilities, etc., as distinguished from raw land.

Improvement Location Certificate

An Improvement Location Certificate (“ILC”) is primarily used by mortgage and/or title companies to assist in residential property transactions. This certificate typically documents the location of improvements upon a parcel of land and graphically shows the location of easements and/or other encumbrances affecting the property as disclosed in information provided by the title company. Typically, the surveying methods used in the preparation of an “ILC” are not sufficient to precisely determine the location and dimensions of property lines, or the exact location of improvements upon or adjacent to the subject property. Therefore, an “ILC” should not be construed to be a land survey plat or an improvement survey plat. By State law the professional land surveyor who prepares an “ILC” must use a mandated certification that includes the following phrase “…that it is not to be relied upon for the establishment of fence, building or other future improvement lines…” For more information go to the County Surveyor’s page.


Buildings or other relatively permanent structures or developments (such as buildings, fixtures, fences, and water rights) located on or attached to land. Homes and buildings are appraised and valued separately from the land.


Street grading, street surfacing and paving, curb and gutters, street lights, street signs, sidewalks, crosswalks, water mains and lines, water meters, fire hydrants, sanitary sewers, storm drainage facilities, culverts, bridges, public utilities, or other such installations designated by the Planning Commission or Board of County Commissioners.

Income Approach

A set of procedures through which an appraiser derives a value indication for an income-producing property by converting its anticipated benefits into property value. This conversion can be accomplished in two ways. One year’s income expectancy can be capitalized at the market-derived capitalization rate or at a capitalization rate that reflects a specified income pattern, return on investment, and change in the value of the investment. Alternatively, the annual cash flows for the holding period and the reversion can be discounted at a specified yield rate.

Incurable Depreciation

An element of accrued depreciation; a defect caused by a deficiency or superadequacy in the structure, materials, or design, which cannot be practically or economically corrected.

Individual Sewage Disposal System

A system or facility for treating, neutralizing, stabilizing, or disposing of sewage which is not a part of or connected to a sewage treatment facility.

Industrial Property

Land and /or improvements that can be adapted for industrial use; a combination of land, improvements, and machinery integrated into a functioning unit to assemble, process, and manufacture products from raw materials or fabricated parts; factories that render service, e.g., laundries, dry cleaners, storage warehouses, or those that produce natural resources, e.g., oil wells.


Resources (such as roads, bridges, buildings, homes, equipment, utilizes) at risk from hazards.


A means of entering; an entrance.


A professional that has been trained and certified to perform inspections. See also: building inspector, septic systems inspector.


A professional that has been certified to install or repair. See also: septic systems installer.


In real estate, a formal, legal document, e.g., a contract, a deed, a lease, a will.

Intangible Personal Property

Nonphysical items of Personal Property A right rather than a physical object; consists of trademarks, patents, copyrights, stocks, bonds, and computer software not used as built-in machine language initiated during the computer startup. Except for public utility valuation, all intangible personal property is exempt from property taxation in Colorado.


The condition of dying without leaving a valid will.

Investment Property

Property that constitutes a business enterprise consisting of all tangible and intangible assets assembled and developed as a single unit of utility for lease or rental, in whole or in part, to others for profit; normally purchased in expectation of annual net income and/or capital gain.

Irrigation Ditch

A long narrow excavation dug in or placed on grade for carrying water which is listed in the Boulder County Ditch and Reservoir Directory.


Joint Tenancy

Joint ownership by two or more persons with the right of survivorship.

Junk Yard

A building, structure, or parcel of land, or portion thereof, used for the collecting, storage or sale of waste paper, rags, scrap metal, or discarded material; or, for the collecting, dismantling, storage, salvaging, or demolition of vehicles, machinery or other materials. Considered a General Industrial use.



A small, self-standing structure located in the jail lobby or alternative sentencing building. The kiosk allows you to place money on an inmate’s account by using cash or a credit card. There is a fee associated with using the kiosk.


Ladder Fuels

Materials that provide vertical continuity between the surface fuels (such as grass and duff) and crown fuels (tree canopies, pine needles) that contribute to a fire moving into the crowns of trees. These are generally shrubs and/or small seedling and sapling size trees that can act as a ladder for fire to get into the crowns of the larger trees (e.g. from dead fuels to lower branches to other intermediate trees and shrubs to the upper tree canopies).

Land or Site Analysis

A careful study of factual data relating to the neighborhood characteristics that create, enhance, or detract from the utility and marketability of the land or site as compared with competing, comparable land or sites.

Land Use Analysis

A systematic study of an area or region that documents existing conditions and patterns of use, identifies problem areas, and discusses future options and choices. As part of the general planning process, such an analysis might cover topics such as traffic flow, residential and commercial zoning, sewer services, water supply, solid-waste management, air and water pollution, or conservation areas. In short, any factors that could affect how particular areas of land should, or should not, be used.

Land-To-Building Ratio

The proportion of land area to gross building area; typical land-to-building ratios for properties combine land and building components into a functional economic unit.

Leasehold improvements

Additions or remodeling permanently made by a lessee.

Legal Description

A description of land that identifies the real estate according to a system established or approved by law; an exact description that enables the real estate to be located and identified.

Legal Owner

The owner of title, as distinguished from the holders of other interests, e.g., beneficial or possessory interests.

Level of Value

The value as established for a statutorily prescribed appraisal date.

License Fee

License fee is based on the empty weight of the vehicle (CWT) and vehicle type. Additional fees that may be included in the license fee are based on vehicle type, age of vehicle, fuel type, and material fees (plates and validation stickers) are: Highway user fee; Emission fee; Diesel fee; Emergency Medical Services fee; Motorist Insurance Identification fee; and Peace Officer Standards & Training fee.

Issuance of Designer plates, Special Organizational plates and Military plates will increase the license fee by $50.00 for the first time issuance and at time of replacement. Designer plate registration will include an additional $25.00 annually assessed at time of renewal.

Light Trespass

Light falling where it is not wanted or needed, typically across property boundaries.

Limb (de-limb)

To remove branches from a tree (a.k.a. pruning).

Limited Partnership

An ownership arrangement consisting of general and limited partners. General partners manage the business and assume full liability for partnership debt, while limited partners are passive and liable only to the extent of their own capital contributions.


Farm animals kept or raised for pleasure, food for human or animal consumption, breeding, draft, or profit.

Living Trust

A trust that becomes effective during the lifetime of its creator, as distinguished from a trust under a will.


A distinct piece of land; a piece of land that forms a part of a district, community, city block, etc.

Lot Area

The area of the horizontal plane within the lot lines of a lot.

Lot Line

Subdivided land in plats recorded prior to October 19, 1994:

A. FRONT That part of a property line dividing a lot from a road. On a corner lot, only one property line shall be considered as a front line. The shorter property line shall be considered the front unless the property owner chooses another property line dividing the lot from a road.

B. REAR The line opposite and parallel to the front line. In the event no lot line is opposite and parallel to the front lot line, there shall be no rear.

C. SIDE All lot lines other than front lot lines or rear lot lines. A triangular lot has two side lot lines and no rear lot line.

Unsubdivided land, and subdivided land in plats recorded on or after October 19, 1994:

A. FRONT That part of a property line dividing a lot from a road, exempting private thoroughfares which are not in subdivided land. On a corner lot or other lots with multiple frontages, all street frontages shall be governed by front yard regulations.

B. REAR The boundary line opposite and parallel to the front line. In the event no lot line is opposite and parallel to the front lot line, there shall be no rear.

C. SIDE All lot lines other than front lot lines or rear lot lines. A triangular lot has two side lot lines and no rear lot line.


The complete lighting assembly (including the lamp, housing, reflectors, lenses and shields), less the support assembly (pole or mounting bracket); a light fixture.


Manufactured Home

A. A structure, transportable in one or more sections, which, when erected on site, is 320 or more square feet, and which is built on a permanent chassis. These homes are designed to be used for residential purposes, with or without a permanent foundation when connected to the required utilities, and contain the necessary plumbing, heating, air-conditioning, and electrical systems. A home which does not meet the minimum size requirements stated above, is a manufactured home if it either (1) is certified as such by HUD pursuant to the federal Manufactured Home Construction and Safety Standards Act, 41 U.S.C. 778 5401, et. seq., as amended, or (2) complies with the NFPA 501B/ANSI A119.1 (1973, 1974 and 1975 editions).

B. A manufactured home also means a residential building which, whether or not a manufactured home as defined above (and which under the County’s prior regulations may have been defined as a mobile home), is either:

1. Located in a legally existing manufactured home park in the unincorporated County on the rezoning date; or

2. Proposed to be relocated onto a legal manufactured home space in a manufactured home park; predates the certification requirements of the Federal Manufactured Home Construction and Safety Standards Act and NFPA 501b/ANSI a119.1 (1973 through 1975 editions); and is inspected by the Chief Building Official and determined to be in a safe, sound physical condition and to meet any other requirements for such homes as may be specified in the County’s Building Code.

C. The term manufactured home shall not include travel trailers, camper trailers, campers or self-contained motor homes or camper buses.

Manufactured Home Park

A parcel upon which two or more manufactured homes, occupied or intended to be occupied for dwelling purposes, are located.

Manufactured Home Space

A portion of ground within a manufactured home park designated for the permanent location of one manufactured home.

Market Area

A group of properties, identified by a combination of geography and use, that are subject to similar economic forces.

Market Value

The most probable price, as of a specified date, in cash, or in terms equivalent to cash, or in other precisely revealed terms for which the specified property right should sell after reasonable exposure in a competitive market under all conditions requisite to a fair sale, with the buyer and seller each acting prudently, knowledgeably, and for self-interest, and assuming that neither is under undue duress.

Mass Appraisal

The process of valuing a universe of properties as of a given date utilizing standard methodology, employing common data, and allowing for statistical testing. See also The mass appraisal process.

Metes and Bounds System

A system for the legal description of land that refers to the parcel’s boundaries, which are formed by the point of beginning (POB) and all intermediate points (bounds) and the courses or angular direction of each point (metes).


A living single cell that is too small for the human eye to see.


One-tenth of one cent; often used to express real estate taxes.

Mill Levy

A tax rate expressed in tenths of a cent; e.g., a tax rate of one mill per thousand means $1 of taxes per $1000 of assessed value.

Mines, quarries, and minerals

Real property including all rights and privileges connected with mines and quarries in and under the land and the minerals connected with it.

Minor Modification

A change which does not result in increased impacts or a greater intensity of either the uses of the development or in the activity under consideration.


An effort made to reduce or eliminate the impacts of injury or damage from a natural hazard or disaster.

Mountainous Areas

The area west of Colorado Highway 93 from its intersection with the south county line to the City of Boulder, west of the City of Boulder city limits, west of US 36 from City of Boulder to Colorado Highway 66, and west of the St. Vrain Supply Canal from Colorado Highway 66 to its intersection with the north county line.

Moveable Objects

Items not anchored to the ground that are subject to being transported by water, including trailers, automobiles, manufactured homes, tanks, trash dumpsters, lumber, or other materials.

MSRP (Manufacturer’s Suggested Retail Price)

The manufactures suggested retail price of a motor vehicle including any accessory or item of optional equipment physically attached to such vehicle prior to the sale to the purchaser. The MSRP is used to determine the taxable value.

Note: The purchase price cannot be used for the MSRP.

Multiple Regression

Multiple Regression Analysis (MRA) is a statistical method to predict the market value of all properties as of the appraisal date, based on actual sales in comparable areas (neighborhoods). MRA models create adjustments based on the contributory value of characteristics such as quality, age, architectural style, and square footage.

Multiple Use

A combination of compatible land uses in an area.

Municipal Separate Storm Sewer System (MS4)

Publicly-owned facilities by which storm water is collected and/or conveyed, including but not limited to any roads with drainage systems, municipal streets, gutters, curbs, catch basins, inlets, piped storm drains, pumping facilities, retention and detention basins, natural and human-made or altered drainage ditches/channels, reservoirs, and other drainage structures.

Municipal Writ Of Execution

The court requires that the defendant pay a cash fine or remain in jail until the cost of the fine is worked off. The defendant receives $50.00 a day credit towards the fine for each day they are in custody.



A neighborhood is defined as a geographic area established by commonality based on land uses, types and age of building or population, the desire for homogeneity, or similar factors. Neighborhood is described as the location of a property that has a direct and immediate effect on value.


An oxidized salt compound made up of nitrogen and oxygen. Nitrate is a waste byproduct that is commonly found in wastewater.

No Bond

A defendant does not qualify for a Bond until seen by a judge. In most cases this should happen within 48 hours of the arrest.

Noncombustible Materials

A material that, in the form in which it is used, is either one of the following: 1) Material of which no part will ignite and burn when subjected to fire, or 2) Material having a structural base of noncombustible material as defined in the previous item, with a surfacing material not over 1/8 inch thick, which has a flame-spreading rating of 50 or less (flame-spreading rating obtained to tests conducted in ASTM E 84-91a). Noncombustible does not apply to surface finish materials.

Notice of Valuation

The Assessor must notify the property owner of any change in value. The “NOV” is mailed no later than the 1st of May for real property and June 15th for personal property each year. This provides the property owner with the opportunity to appeal the value.



One cause of depreciation; and impairment of desirability and usefulness caused by new inventions, changes in design, improved processes for production, or other external factors that make a property less desirable and valuable for a continued use; may be either functional or external.

Oil and Gas Operation

Any structure, facility, or activity which is constructed on or disturbs land in association with oil or gas drilling, production, or waste treatment and disposal, including but not necessarily limited to wells, tanks or tank batteries, pits, access roads for ingress and egress, and pipelines.


Opaque means that a material does not transmit light from an internal illumination source. Applied to sign backgrounds, means that the area surrounding any letters or symbols on the sign either is not lighted from within, or allows no light from an internal source to shine though it.


A designated portion of subdivided land which, unless otherwise noted on the plat, is not a building lot.


An improvement that does not represent the most profitable use for the site on which it is placed because it is too large or costly and cannot develop the highest possible land value; may be temporary or permanent.


Vegetation that forms the uppermost layer of a forest or shrub community. These are most often trees or shrubs that grow best in the open (dominant) or with other trees (co-dominant).

Owner of Record

The owner of title to a property as indicated by public records.

Ownership Tax

Ownership tax is based on the vehicle year of manufacture and the taxable value of the vehicle. The taxable value will not change during the life of the vehicle. The calculation used to determine ownership taxes due will change as the vehicle ages.

Ownership tax is always calculated for 12 months based on the month following the month of application for registration through the determined expire month next year.


An onsite wastewater system, commonly referred to as a septic system. An absorption or dispersal system of any size or flow or a system or facility for collecting, storing, treating, neutralizing, stabilizing, or disposing of domestic-type sewage which is not part of, or connected to, a sewage treatment works.



All contiguous land held under one deed, except where a portion of the land is designated a building lot pursuant to the provisions of the Boulder County Land Use Code.


A piece of land of any size in one ownership.

Parcel Number

A code number that serves as an abbreviation of, or replacement for, a parcel’s legal description; used to facilitate the storage and use of land data in an information system; may be based on geocodes, government surveys, or tax maps.

Partial Interest

Divided or undivided rights in real estate that represent less than the whole.


A business arrangement in which two or more persons jointly own a business and share in its profits and losses.

Personal Property

Identifiable portable and tangible objects that are considered by the general public to be “personal”, e.g., furnishings, artwork, antiques, gems and jewelry, collectibles, machinery and equipment; all property that is not classified as real estate. Personal property includes movable items that are not permanently affixed to, and part of, the real estate.

Personal Recognizance Bond (PR)

A dollar amount of the bond is established, however the defendant only has to sign the bond promising to appear on the future court dates. The defendant must have a mailing address and be approved through the courts or Bond Commissioners.


A plan, map, or chart of a city, town, section, or subdivision indicating the location and boundaries of individual properties.


A map of certain described subdivided land, including supporting materials, which constitutes an instrument for recording real estate interests, is prepared and approved in accordance with the Subdivision Regulations, and is recorded in the office of the County Clerk and Recorder. The term “plat,” as used in this Code as a reference to subdivided land, does not include any map, depiction, or document of any kind describing unsubdivided land, even though the term “plat” may be used in such document (for example, a document denominated as a “survey plat” or “subdivision exemption plat” which does not describe divisions of land approved pursuant to the Subdivision Regulations).

(as a verb:) To undertake and accomplish the process of creating subdivided land.

Plat Book

A record showing the location, size, and owner of each plot of land in a stated area.

Plot Plan

A plan showing the layout of improvements on a property site or plot; usually includes location, dimension, parking areas, landscaping, and other features.

Point of Beginning(POB)

A survey reference point that is tied into adjoining surveys. In a metes and bounds description, courses that connect monuments or points are generally described from this point.

Possessory interest

Please see the Possessory interest web page on this site.

Power of Attorney

A legal instrument in which a person authorizes another to act as his or her attorney or agent.

Power Plant

An electrical energy generating facility with generating capacity of more than 50 megawatts and any appurtenant facilities.

Preliminary Plan

A map of land proposed to become subdivided land, and specified supporting materials, whose purpose is to allow evaluation of the feasibility of and preliminary engineering design for the development, prior to the applicant undertaking more detailed engineering and design work. The preliminary plan is the second of the three required steps (sketch plan, preliminary plan, and final plat) for obtaining approval of subdivided land, and must be consistent with the approved sketch plan.

Prescribed Burn

The controlled application of fire to fuels in a predetermined area. Done under controlled or known conditions of weather, fuel moisture. Conducted for specific management objectives, such as fuel reduction, weed control, growth stimulation, sanitation.

Principal Use

The primary purpose or function for which a parcel is used.

Prior Ownership Tax

Ownership Tax is equivalent to personal property tax. Prior ownership taxes are calculated from the month following the month of purchase through the month of the application for registration.

Example: Month following the month of purchase is February. Month of application for registration is March. Prior ownership taxes will be assessed for two months of prior ownership taxes.

Private Access

An access road that serves more than two separate buildings or structures. These are generally routes that access multiple home sites and are privately maintained.

Professional Bail Bondsman

A bail bond agent, or bondsman, is any person or corporation, which will act as a surety and pledge money or property as bail for the appearance of a criminal defendant in court.

Property Bond

This type of bond requires the courts approval. The defendant or family, friends, etc. must post property with the court that is of greater value than the bond. The courts would retain legal title to the property and could sell it in the event the defendant fails to appear in court.

Public Improvement

Any drainage ditch, roadway, parkway, sidewalk, pedestrian way, tree, lawn, off street parking area, lot improvement, or other facility which benefits the public.

Public Water and Public Sewer Facilities

Those facilities of a municipality or a sanitation and/or water district which are organized and operated pursuant to State Statute.


A point in a roadway where one vehicle can pull over off the main travel way out of traffic flow, or where two vehicles going opposite directions can pass one another on a one-lane road. No change in direction of the primary vehicle is intended (compare to a “Turnaround”).

Purchase Date

The purchase date is used to calculate prior ownership taxes due from the date of sale to date of registration. If you have not purchased the vehicle enter the estimated purchase date.



Quality descriptors are based on standard ratings of Low, Fair, Average, Good, Very Good, Excellent and Exceptional. A “plus” (+) or “plus plus” (++) rating reflects higher quality attributes from the building’s interior, exterior and overall design which contribute to additional market appeal. For example, attributes such as above-average interior trim, custom kitchen design, or unique architectural embellishments add to the property’s quality rating. The “plus” ratings distinguish higher quality differences in properties as demonstrated in the market. These rating adjustments are useful in the mass appraisal of large numbers of properties.

Quitclaim Deed

A form of conveyance in which any interest the grantor possesses in the property described in the deed is conveyed to the grantee without warranty of title.



A parcel of land that is used for grazing livestock for the primary purpose of obtaining a monetary profit.


A term to describe longitudinal segments of a river, creek, or other watercourse.

Real Estate

Physical land and appurtenances attached to the land, e.g., structures. An identified parcel or tract of land, including improvements, if any.

Real Property

All interests, benefits, and rights inherent in the ownership of physical real estate (considered to be permanently fixed in nature such as land, and improvements on the land); the bundle of rights with which the ownership of the real estate is endowed. In some states, real property is defined by statute and is synonymous with “real estate”.


Review and adjustment of property value to a different level of value.


The process in which all property within a taxing jurisdiction is revalued to assign new assessed values.


The last phase of any valuation assignment in which two or more value indications derived from market data are resolved into a final value estimate, which may be either a final range of value or a single point estimate.

Recorded Map

A map of a parcel of land that has been filed in the office of the County Clerk and Recorder; e.g. “As per map recorded in book 56 at page 20”


The filing of a copy of a legal instrument or document, e.g., a deed, in a government office provided for this purpose; creates a public record of the document for the protection of all concerned and gives constructive notice to the public at large.

Recreational Vehicle

A vehicle which is:

A. Built on a single chassis;

B. 400 square feet or less when measured at the largest horizontal projection;

C. Designed to be self-propelled or permanently towable by a light duty truck; and

D. Designed primarily not for use as a permanent dwelling but as temporary living quarters for recreational, camping, travel, or seasonal use.

Rectangular Survey System

A system for the legal description of land that refers to the parcel’s location in a township, an area approximately six miles square that is formed by the intersection of principal meridians and base lines. Each township contains 36, one-square-mile sections of 640 acres.

Registration date

Registration date is the date when plates and registration is issued to your vehicle. The registration date is used to calculate ownership taxes due for the twelve- month period. If you do not have a definite registration date enter the estimated registration date.


An amendment or change to a plat which exceeds the scope of a correction plat and is approved according to the applicable provisions of the Subdivision Regulations, or the Exemption Plat provisions of Article 9. In the discretion of the Director, replats which cannot be processed as Exemption Plats may, in accordance with the Subdivision Regulations, require sketch plan, preliminary plan, and final plat review, or preliminary plan and final plat review, or simply final plat review, depending upon the nature of the proposed change with reference to the definitions and purposes of the three required steps for obtaining approval of subdivided land.

(as a verb): To undertake and accomplish the process of amending or changing a plat.


Any property used as a dwelling; in law, the legal domicile; used for owner occupancy, not investment income.

Residential Floor Area

For the purposes of Site Plan Review and the presumptive size thresholds associated with the Expanded Transfer of Development Rights Program, Residential Floor Area includes all attached and detached floor area (as defined in 18-162) on a parcel including principal and accessory structures used or customarily used for residential purposes, such as garages, studios, pool houses, home offices, and workshops. (Exemptions: Gazebos and carports under 200 square feet each, up to 400 square feet total.)

Right of Survivorship

Right of surviving joint tenant to acquire the interest of the deceased joint tenant in joint tenancies and tenancies by the entirety without any probate proceedings.


Land occupied or intended to be occupied by a public crosswalk, trail, road or other public transportation use; or railroad, electric transmission line, or other utility uses.


The possibility/probability of sustaining a loss or injury; something that creates or suggests a hazard.


A public or private thoroughfare which affords a means of access to abutting property.

Road Profiles

A drawing of an existing or proposed vertical section of a road, street, or alley, which may include curb, gutter, and sidewalk. It may be a true or exaggerated profile, and may reflect either a centerline and/or both flow lines of a road, street or alley.

Road Safety Surcharge

Provides for “Funding Advancement For Surface Transportation and Economic Recovery as described in Senate Bill 09-108. This surcharge shall be imposed on any registration made on or after July 1, 2009.


Precipitation which enters downstream waterways or properties.


Sales Comparison Approach

A set of procedures in which a value indication is derived by comparing the property being appraised to similar properties that have been sold recently, applying appropriate units of comparison, and making adjustments to the sale prices of the comparables based on the elements of comparison. The sales comparison approach may be used to value improved properties, vacant land, or land being considered as though vacant; it is the most common and preferred method of land valuation when comparable sales data are available.

Sales-Ratio Analysis

A study of the relationship between actual values and sale prices and the deviations that result from differences between the two; used to determine the efficiency and fairness of the assessment process in a particular jurisdiction.


A lighting assembly designed to direct the output of a contained lamp in a specific tightly focused direction (a beam) with a reflector located external to the lamp, and with a swiveled or gimbaled mount to allow the assembly to be easily redirected. Such lights are used commonly to sweep the sky for advertisement purposes.


In the government survey system of land description, one of the 36 sections, each one mile square, into which each township is divided.


The defendant is released upon completion of his required amount of time of incarceration. The courts often modify a sentence so releases may occur earlier.

Septic systems inspector

A professional that has been trained and certified to perform inspections of septic systems

Septic systems inspector list (PDF)

Septic systems installer

A professional that has been certified to install or repair septic systems


The required minimum distance between the building and the related front, side, or rear lot line. (See Article 7-1403 of the Boulder County Land Use Code – Supplemental Requirements for Yards Along Major Roads)


Refuse liquids or waste matter typically carried off site by a sewer system or treated on site by an on-site wastewater system.

Site Specific Development Plan

A plan which has been submitted to the County as part of a special use, final plat, or final plat replat approval, to establish a vested right pursuant to Part 1 of Article 68 of Title 24, C.R.S., as amended, describing with reasonable certainty the type and intensity of the proposed land use for a specific parcel or parcels of property (see Boulder County Land Use Code Section 3-207).


In real estate, the physical location of a property; in personal property, the taxable location because personal property may be moved from one place to another.

Sketch Plan

A map of land proposed to become subdivided land, and specified supporting materials, whose purpose is to allow the evaluation of the basic or conceptual feasibility and design characteristics of the development at an early stage in the planning process, in accordance with the Subdivision Regulations. The sketch plan is the first of the three required steps (sketch plan, preliminary plan, and final plat) for obtaining approval of subdivided land.


The debris (limbs, branches, and tops of trees) accumulated as part of forest thinning or harvesting operations.


A standing dead tree, or part of a tree from which at least the smallest branches have fallen. Commonly a result of insect attack or disease, or possibly from a wildfire. Snags are often used by wildlife such as woodpeckers, owls, and various small mammals, either as cover, nesting sites, or as a food source (insects). They may represent a source of firebrands or embers during a wildfire event and may represent a hazard after the fire.

Soil Survey

The soil survey conducted by the U.S. Department of Agriculture in cooperation with the State Agricultural Experiment Stations and other Federal and State agencies.

Solar Access

The ability to receive sunlight across real property for any solar energy device.

Solar Energy Device

A device which converts the sun’s radiant energy into thermal, chemical, mechanical, or electric energy.

Solid Waste

Any garbage, refuse, rubbish, or other discarded materials, which may be in solid, liquid, or gaseous form.

Special Assessment

An assessment against real estate levied by a public authority to pay for public improvements, e.g., sidewalks, street improvements, sewers; an amount levied against individual owners in a condominium or cooperative to cover their proportionate shares of a common expense.

Special Districts

Special service governments created to provide a particular service, e.g., economic development districts, water resource management districts.

Square Foot Cost

The cost of one square foot of an improvement; obtained by dividing the actual, or estimated, cost of a building by its gross floor area or by dividing the actual, or estimated, cost of a land improvement by its square foot area; can be multiplied by the number of square feet in a building or land improvement to produce the actual or estimated cost.

Start of Construction

The first placement of permanent construction of a building or other structure on a site, such as the pouring of slabs or footings or any work beyond the stage of excavation.


Any surface flow, runoff, and drainage consisting entirely of water from any form of natural precipitation, and resulting from such precipitation.


A. A combination of materials forming an edifice or building of any kind, or any piece of work artificially built up or composed of parts joined together in some definite manner, but excluding the following:

  • retaining walls;
  • fences not over 6 feet high;
  • platforms or decks not more than 30 inches above grade and not over any basement or story below;
  • utility mains, lines, and underground facilities; and
  • yard and play equipment.

B. A permanent structure is built of materials in a manner which would commonly be expected to remain useful for a substantial period of time.

C. A temporary structure is built of materials in a manner which would commonly be expected to have relatively short useful life, or is built for a purpose that would be expected to be relatively short-term in duration.

Subdivided Land

Land located within a platted subdivision, as depicted on a plat approved in accordance with the Subdivision Regulations, and recorded in the office of the County Clerk and Recorder.

Subdivided Lot

A designated portion of subdivided land which is intended to be a building lot.


Any parcel of land to be used for condominiums, apartments, or any other multiple-dwelling units, or any parcel of land which is divided into two or more parcels, separate interests, or interests of land, as defined pursuant to C.R.S. Section 30-28-101(10). Subdivisions are generally divisions of land into parcels comprising less than 35 acres occurring on or after May 5, 1972, as further set forth in C.R.S. Section 30-28-101(10). Prior to May 5, 1972, what constituted a “subdivision” of land in the unincorporated County is set forth in the applicable Subdivision Regulations, first passed on March 3, 1954. Subdivisions of land as defined under the applicable Subdivision Regulations require approval under the Subdivision Regulations, unless exempted from such requirements under applicable law.


Any parcel of land to be used for condominiums, apartments, or any other multiple-dwelling units, or any parcel of land which is divided into two or more parcels, separate interests, or interests of land, as defined pursuant to C.R.S. Section 30-28-101(10). Subdivisions are generally divisions of land into parcels comprising less than 35 acres occurring on or after May 5, 1972, as further set forth in C.R.S. Section 30-28-101(10). Prior to May 5, 1972, what constituted a “subdivision” of land in the unincorporated Boulder County is set forth in the applicable Subdivision Regulations, first passed on March 3, 1954. Subdivisions of land as defined under the applicable Subdivision Regulations require approval under the Subdivision Regulations, unless exempted from such requirements under applicable law.

Subdivision Exemption

Pursuant to the authority granted in C.R.S. Section 30-28-101(10)(d), an approval by the Board of County Commissioners to take certain unsubdivided land or divisions of unsubdivided land out of the definition of “subdivision,” with the result that such land or divisions of land do not have to meet the requirements of the Subdivision Regulations. The requirements for Subdivision Exemptions are contained in Sections 9-100 through 9-102 of the Boulder County Land Use Code. Land with approved subdivision exemptions is not platted (subdivided) land, even though it may be described according to a so-called “Subdivision Exemption Plat” as defined in the Colorado surveying statutes in Title 38, C.R.S. Exemptions from the Subdivision Regulations for subdivided land are called “Exemption Plats” and are contained in the Exemption Plat requirements of Sections 9-200 through 9-203 and Section 9-300 of the Boulder County Land Use Code (see also Article 4-300).

Subdivision Regulations

The regulations contained in Article 5 of the Boulder County Land Use Code and predecessor regulations enacted by the County pursuant to the authority granted in Part 1 of Article 28 of Title 30, C.R.S. and predecessor Colorado county planning statutes, which set forth the process and requirements to plat subdivided land.

Substantial Improvement

A. Any cumulative repair, reconstruction, or improvement of a building or other structure, the market value of which equals or exceeds 50 percent of the market value of the structure either before the improvement or repair is started, or if the structure has been damaged and is being restored, before the damage occurred. Substantial improvements are calculated on a cumulative basis, beginning with improvements commenced on or after November 1, 1991.

B. The term substantial improvement does not include:

Either any project for improvement of a structure to comply with existing state or local health, sanitation, safety, or building code specifications which are solely necessary to assure safe living conditions; or

Any alteration of a structure listed on the National Register of Historic Places or on the Colorado State Historical Society’s list of historic places.

Substantial Modification

A change which significantly alters the impacts and/or character of a structure, development, or activity. Considerations relevant to what constitutes a substantial modification of an approved special use are further detailed in Article 4-603.B., and may be relevant to substantial modification determinations for other categories of approvals under the Boulder County Land Use Code.

Surety Bond

The defendant or family, friends, etc. must contact a professional Bail Bondsman to post the bond. The Bondsman has an attached fee for their services and usually requires some type of collateral. Their fee is generally 15% and they usually require a minimum fee to provide the service. The Bondsmen are registered through the state and we maintain a list of unacceptable Bondsman who have defaulted on their bonds. Staff members will not recommend a bondsman.

Surface Fire

A fire that occurs in surface fuels (grasses, forbs, low shrubs) (compare to crown fire).

Survey Monument

Iron, brass or aluminum shaft a minimum of 1/2 inch in diameter with a 24 inch minimum length set in concrete at least five inches in diameter and located in the ground at all points on streets, alleys, or boundary lines where there is a change in direction or curvatures.


Tangible Personal Property

Physical objects such as equipment, furniture, drapes, and free-standing appliances.


A compulsory contribution legally exacted from persons, corporations, and other organizations by a government, for the support of government and the maintenance of public services.

Tax Base

The unit of value to which the tax rate is applied to determine the tax due; for property taxes, the assessed valuation; for income taxes, the net taxable income.

Tax District

A political subdivision of one or more assessment districts where a governmental unit has the authority to levy taxes.

Tax Exemption

Total exemption or freedom from tax; granted to educational, charitable, religious, and other nonprofit organizations. Partial exemptions from ad valorem tax are granted to homesteads in some states.

Tax Levy

In property taxation, the total revenue that will be realized by a tax.

Tax Lien

A lien that is automatically attached to property in the amount of its unpaid property taxes.

Tax Rate

The ratio between that tax and the tax base; applied to the assessed value to determine the amount of tax; obtained by dividing the amount of the tax levy by the total assessed value of all properties in the tax district; usually expressed in dollars per $100 or $1,000 (mills) of assessed value.

Tax Roll

The official list of all taxpayers subject to property tax, the amounts of their assessments, and the taxes due.

Tax Warrant

Annual report showing the taxable assessed valuation for Boulder County by taxpayer and the amount of taxes due. This report includes the legal description and assessed value attributable to land, improvements, or personal property on each property record.


All personal property is taxable unless it is specifically exempt by law.

Taxable Property

All property classified as Real or Personal Property which is not exempt by law.

Taxable Value

A percentage of the MSRP (Manufacturer’s Suggested Retail Price). If the vehicle is a passenger vehicle multiply the MSRP by 85% and the sum is the taxable value. If the vehicle is a light truck multiply the MSRP by 75% and the sum is the taxable value.

The taxable value is used to determine ownership taxes due. You can find the taxable value on your application for title or Colorado title provided to you by the dealer. If you financed your vehicle purchase a Title Complete Notice will be forwarded to you and notes the taxable value.

Note: The purchase price cannot be used for the taxable value. Taxable values do not change throughout the life of the vehicle. The tax factors used to calculate ownership taxes decrease as the vehicle ages.


The right of government to raise revenue through assessments on valuable goods, products, and rights.

Taxing Entity

Political subdivision of the state with the power to levy tax on property that lies within its geographical boundaries.


One who pays or is liable for a tax.


The holding of property by any form of title.

Tenancy in Common

An estate held by two or more persons, each of whom has an undivided interest.

Time Trending

Colorado Statute requires that sales prices be adjusted for time to an appraisal date of the last date of the study period. Time adjusted sales prices reflect market conditions on that date.


The combination of all elements that constitute proof of ownership.


Fire burning through the crown of an individual tree or group of trees, not extending to an entire stand (compare to crown fire).


In the government survey system of land description, the area between two township lines and two range lines; normally contains 36 sections of approximately 640 acres each.

Township Lines

In the governments survey system of land description, survey lines that run east and west at six-mile intervals north and south of a baseline and form the north and south boundaries of townships.


A parcel of land; an area of real estate that is frequently subdivided into smaller parcels.

Trust Deed

A deed that establishes a trust, an instrument that conveys legal title to a property to a trustee, stating the trustee’s authority and the conditions that bind the trustee in dealing with the property.


A person who controls legal title to a property under a trust agreement.


A point in a road where a vehicle can change direction (180°) (compare to pullout). Turnarounds are generally circular, hammerhead or “Y” shaped.



An improvement that is inadequate to develop the highest and best use of its site; usually a structure that is of lesser cost, quality, and size than typical neighborhood properties.


Vegetation that grows underneath the overstory species, or that form a secondary layer. Most often these are shade tolerant shrubs, forbs and grasses.

Undivided Interest

Fractional ownership without physical division into shares.

Uniform Standards of Professional Appraisal Practice (USPAP)

Current standards of the appraisal profession, developed for appraisers and the users of appraisal services by the Appraisal Standards Board of the Appraisal Foundation. The Uniform Standards set forth the procedures to be followed in developing an appraisal, analysis, or opinion and the manner in which an appraisal, analysis, or opinion is communicated. They are endorsed by the Appraisal Institute and by other professional appraisal organizations.

Unimproved Land

Vacant land or land that lacks the essential, appurtenant improvements required to make it useful.

Units of Comparison

The components into which a property may be divided for purposes of comparison, e.g., price per square foot, front foot, cubic foot, room, bed, seat, apartment unit.

Unsubdivided Land or Unsubdivided Parcels

Land or parcels which do not fall within the definition of subdivided land (i.e., land or parcels which are not within a platted subdivision).

Urbanized Area

As used in the Boulder County Land Use Code Article 7-904… A land area comprising one or more places – central place(s) – and the adjacent densely settled surrounding area – urban fringe – that together have a residential population of at least 50,000 and an overall population density of at least 1,000 people per square mile.

Useable Area

The actual occupiable area of a floor or an office; computed by measuring the finished surface of the office side of corridor and other permanent walls, to the center of partitions that separate the office from adjoining usable areas, and the inside finished surface of the dominant portion of the permanent outbuilding walls. The usable area of a floor is equal to the sum of all usable areas of that floor. No deductions are made for columns and projections necessary to the building.

Utility Storage Area

Any surface facility designed to store 50 million cubic feet or more of natural gas; or, 35,000 barrels or more of petroleum derivatives.


Vacant Building Lot

For the purposes of the Expanded Transfer of Development Rights Program under Article 4-1300 of the Boulder County Land Use Code, a vacant building lot is a lot that qualifies as a building lot under the Boulder County Land Use Code, but has no structures on it, except for improvements that are minor in nature and do not compromise the overall open land quality of the lot.


The process of estimating the market value, insurable value, investment value, or some other properly defined value of an identified interest or interests in a specific parcel or parcels of real estate as of a given date. Valuation is a term used interchangeably with appraisal.


The monetary worth of a property, good, or service to buyers and sellers at a given time; 2. The present worth of the future benefits that accrue to real property ownership.

Vehicle Type

The passenger vehicle category includes sedan (4 door), coupe (2 door), convertible (CV), hatchback or lift back (3 or 5 door) station wagon (SW), passenger van (PV), and passenger utility (UP) or sport utility (SUV). The light truck vehicle category includes open bed pick up (PK) trucks and cargo vans (VN) with an empty weight of 16,000 lbs or less. This estimation program will not calculate registration fees for heavy-duty commercial trucks such as dump trucks, trash trucks, etc.

Vested Property Right

As defined in C.R.S. 24-68-102(5), the right to undertake and complete the development and use of property under the terms and conditions of a County-approved site specific development plan (special use, final plat, or final plat replat approval), as implemented through an executed and recorded development agreement. Unless otherwise specified in the site specific development plan approval, a property right shall remain vested for a period of three years.


Warranty Deed

A deed that conveys to the grantee title to the property free and clear of all encumbrances, except those specifically set forth in the document.

Water Surface Elevation

The projected heights in relation to Mean Sea Level (as established by U.S.G.S.. datum) reached by floods of various magnitudes and frequencies.


The specific land area that drains water into a river system or other body of water.

Weighted Average

An average in which each component is adjusted by a factor that reflects its relative importance to the whole; obtained by multiplying each component by its assigned weight, adding the products, and dividing the sum of the products by the sum of the weights.


An open fire that can spread unconstrained through the environment. If not quickly controlled, the result can be a firestorm, often termed a “conflagration,” which destroys large amounts of property and threatens lives. Since prehistoric times, wildfires have been a natural force in shaping and changing Colorado’s landscape. Many of the native tree, brush, and grass species have evolved into fire-dependent vegetation. Some are so fire dependent that their combustibility increases with age, thus assuring renewal and continuation of the species. Lightning provides the ignition for most of these naturally occurring fires. Increasingly, human-caused fires may also become firestorms.

Wildfire Hazard

As defined in the Colorado Land Use Act – A wildfire phenomenon that is so adverse to past, current or foreseeable construction or land use as to constitute a significant hazard to the public health and safety or to property. The term includes but is not limited to slope and aspect; wildfire behavior characteristics; and existing vegetation types.

Wildfire Mitigation Plan (WMP)

A plan to reduce wildfire hazards around a home or on a property. It is a document prepared for a specific project or development proposal in the WUI. It describes ways to minimize and mitigate the fire problems created by the project or development, with the purpose of reducing impact on the community’s fire protection delivery system.


An area in which development is essentially non-existent, except for minor roads, railroads, power lines, and similar transportation facilities. An example of area in Boulder County that conforms to this description is the North Saint Vrain drainage.

Wildland Urban Interface (WUI)

A term used to describe areas where structures (most commonly homes and other related development) are built in otherwise undeveloped natural areas where infrastructure and other human disturbance is minimal. The WUI can be further described as interface (where areas of development directly abuts wildlands, such as the City of Boulder), intermix (where development is scatted amongst forested or native vegetation, as is the case in many mountain subdivisions in unincorporated Boulder County), or occluded (concentrated development, such as a townsite, situated in an area surrounded by wildlands). This human encroachment into the wildland is an area at increased risk of loss to wildfires.



The space which lies between the lot line and the nearest point of a structure. The minimum yard required is defined for each zoning district.



The public regulation of the character and extent of real estate use through police power; accomplished by establishing districts or areas with uniform restrictions relating to improvements; structural height, area, and bulk; density of population; and other aspects of the use and development of private property.


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