How it Works
Density bonuses allow greater density to be built on a site than would otherwise be allowed through underlying zoning. Density bonuses are often granted as an incentive to encourage preferred types of development activity. Some communities grant density bonuses for additional protection of open space, for example, beyond what is required by the underlying zoning, or for higher-quality building design or provision of other amenities. While the exact bonus granted is typically considered on a case-by-case basis, the amount of additional density granted is usually roughly proportional to the amount of benefit provided. Any additional density allowed can be subject to design standards that ensure a high level of site protection and building quality; such standards can help promote community buy-in for the bonus program.
Density bonuses can be somewhat challenging to introduce in a community. Depending on why a density bonus is issued, it is important to have a process by which the local government can ensure that both ends of the bargain are maintained. For example, if a developer is issued a density bonus for conserving land in a geologic hazard area, the local government should require a permanent conservation easement to protect that area in perpetuity in exchange for the added density. (Conservation easements are profiled in the “Protecting Sensitive Areas” section.)
The community should consider the following basic steps:
- Define the purpose of the program. It is important that density bonuses be tied to the goals and policies of a community’s comprehensive plan.
- Identify where density bonuses are permitted. Consider whether the incentives should apply to all zoning districts, only areas meeting certain conditions, or on a case-by-case basis.
- Develop the specifics of the program. Identify the degree to which incentives are issued, whether they are permitted by right or require a public hearing, and other conditions or agreements that must accompany the program.
Density bonuses are often used in tandem with conservation subdivisions, which are addressed in a separate profile. Garfield County provides density bonuses for conservation subdivisions in Section 7-501 of the Land Development Code. The applicant may propose a density neutral development plan, by which the overall density is not increased, but the lot sizes may be reduced to preserve the remainder of the parcel as open space. The applicant may also propose an increased density development plan, by which the calculation of total bonus lots permitted depends on the total expected yield allowed under the base zoning district and the proposed percentage of open space preserved.
The Town of Milliken issues conservation density bonuses for rural subdivisions that conserve areas in the 100-year floodplain, wetlands, valuable habitat areas, and natural geologic hazard areas (as defined by the Colorado Geological Survey). Rural subdivisions are permitted development up to a maximum of one unit per 20 acres by right. A conservation density bonus increases that maximum density to one unit per five acres.
Density bonuses can be effective ways to not only protect hazard areas, but also to direct growth toward desirable areas throughout a community as identified in the comprehensive plan. Other benefits include:
- Increased opportunity for developers to boost their bottom line. By purchasing development rights, a developer can increase the number of units and realize a higher profit.
- Increased density where the community wants it. Densifying receiving areas can result in a more diverse housing stock, can help boost surrounding commercial areas, and could potentially result in development of affordable housing units not otherwise feasible without the added density bonus.
- Density bonuses provide a direct incentive to a developer without requiring complex negotiations often associated with Transfer of Development Rights (TDRs).
- Density bonuses can be calibrated to be either by-right or discretionary, depending on community values and political climate.
- Density bonuses provide a community benefit without requiring public funding.
Challenges include the following:
- Requires additional maintenance to determine that the exchange of density is met with the agreed conservation in perpetuity.
- Like TDRs, density bonuses must be calibrated to local market demands, or the program might not be used.
- Requires education to inform the public about appropriate trade-offs for increased density in some areas.
Key Facts
- Administrative Capacity: Experienced planner with city or county attorney to write ordinance; skilled planners to administer
- Mapping: Not typically, although maps indicating sensitive or hazardous lands may be required as part of the development application process
- Regulatory Requirements: Land use and subdivision regulations
- Maintenance: Some on-going tracking with explicit documentation of density bonuses is required
- Adoption Required: Yes
- Statutory Reference: N/A
- Associated Costs: Ordinance development or amendment costs and staff time to review density bonus applications