Differences Between Miami's Form-Based Code and Traditional Zoning Code in Integrating Planning Principles

Abstract

Problem, research strategy, and findings: Form-based codes (FBCs), by definition, put more emphasis on built-form characteristics than do traditional zoning codes. Several municipalities are adopting FBCs as an alternative to Euclidean (traditional) zoning codes to achieve certain objectives; however, the extent to which these codes differ in integrating important planning and design criteria has not been examined. We use a case-study method and evaluate the extent to which the FBCs adopted by the City of Miami (Miami 21), as compared with the city's previous code (Ordinance 11000), reflects the Leadership in Energy and Environmental Design for Neighborhood Development (LEED-ND) criteria. We evaluate the contents of these codes on a 5-point scale for their concordance with LEED-ND criteria. The results indicate that Miami 21 generally goes beyond Ordinance 11000 in reflecting LEED-ND criteria; however, some of the important criteria, such as mixed-income diverse communities and certified green building, deserve more attention in Miami 21.

Takeaway for practice: Planners in municipalities seeking alternatives to their traditional zoning code should not only consider replacing it with an FBC, but also to integrate planning principles that LEED-ND incorporates to strengthen the proposed code. They can benefit from the findings of this study when determining the extent to which certain built-form characteristics and LEED-ND criteria should be emphasized and in choosing an appropriate alternative to traditional zoning codes.

Keywords:

• form-based codes
• LEED-ND criteria
• Miami 21
• zoning regulations

Acknowledgements

The authors would like to thank the five anonymous reviewers for their important comments. We owe a special note of thanks to Asiya Natekal for her research assistance.

Notes

i . This is based on Miami's estimated population of more than 414,000 in 2012 (U.S. Census Bureau, 2010).

ii . For instance, a transect-based code permits multistory buildings in urban zones, but not in rural or suburban zones, to minimize the possibility of facilitating tall office towers in rural areas (Duany & Talen, 2002).

iii . Rangwala (2012) identifies three types of FBCs based on the implementation strategy adopted by jurisdictions: 1) mandatory codes, 2) optional codes, and 3) floating-zone codes. Mandatory FBCs are obligatory. Optional FBCs may be used voluntarily in place of the existing traditional zoning code. Floating-zone codes can be used when it is deemed that undeveloped land is not yet ready for development. These floating-zone codes are applicable only when a property needs rezoning.

iv . Given that the development of the LEED-ND rating system is influenced by the Congress for the New Urbanism (CNU) to some extent, and Miami 21 was developed by Andres Duany and Elizabeth Plater-Zyberk, founding members of CNU, we expected that Miami 21 would reflect LEED-ND criteria to a greater extent than Ordinance 11000.

v . We evaluated Miami 21 and Ordinance 11000 using prerequisites that must be satisfied and optional credits for which points could be earned. Because there is considerable overlap in the intent between most credits and prerequisites, and given that the credits generally require higher standards to achieve points, the findings related to LEED-ND prerequisites are not included in this study for the purpose of brevity. The results related to prerequisites are available from the corresponding author upon request.

vi . Miami 21 divides the city into 11 transect zones, while Ordinance 11000 divides the city into 14 zoning districts. However, both codes use groupings of zones to regulate zones of certain similar characteristics. The findings are presented using these groupings of zones (seven zones for Miami 21 and nine zones for Ordinance 11000).

vii . For instance, in addition to bonuses that pertain to dwelling unit, square footage, and parking offered in Ordinance 11000, Miami 21 offers incentives that pertain to building height, site design, lot area, and design standards for building areas above the eighth floor. Further, while both Miami 21 and Ordinance 11000 require contribution to an Affordable Housing Trust Fund, Miami 21 does not require a Major Special Use Permit for the application of these development bonuses.

viii . Moreover, there is a notable difference between the two codes in how they address tree-lined streets in their regulations specific to zones. Miami 21 requires street trees in all zones, except the Civic zone, and shaded streets in the T6 zone, whereas Ordinance 11000 encourages street trees only in the Commercial zone.

ix . This is because the LEED-ND rating system defines compact development in terms of greater development capacity: more dwelling units per acre for residential density and greater floor–area ratio for nonresidential density.

x . Ordinance 11000 addresses green buildings and their qualifications for development incentives in a single special district, the Miami Worldcenter project area; however, special districts were excluded from this analysis and thus are not included in our findings.

xi . Ordinance 11000 addresses historic preservation in specific zones through the use of special permits, overlay districts, and planned unit developments; however, given the objectives of this study, these special regulatory tools were excluded from this analysis.</nr>