Zoning reform for advancing sustainability: insights from Denver’s form-based code

ABSTRACT

Many municipalities are adopting form-based codes (FBCs) for advancing the sustainability of development and for facilitating sustainable design criteria that are difficult to achieve under conventional zoning codes (CZCs). The City of Denver recently adopted a citywide FBC. A case-study method was used to examine the extent to which Denver’s FBC differs from the CZC in integrating sustainable design criteria included in the LEED-ND rating system. The results indicate that Denver’s FBC addresses most LEED-ND criteria more strongly than does the CZC; however, some criteria deserve more attention. The paper concludes with recommendations for Denver’s FBC and for other municipalities that are considering zoning reform.

Acknowledgements

We owe a special note of thanks to city planners at the City of Denver who were supportive of our research and provided valuable information and zoning maps. We are grateful for the insights provided by the interviewees for this research.

Notes

1. Within this framework, the first six neighbourhood contexts (Suburban, Urban Edge, Urban, General Urban, Urban Center and Downtown) include a total of 106 zoning districts, while the Special Contexts and Districts include another 29 districts.

2. The FBC for the three Main Street zones along Colfax Avenue, which is generally referred to as Denver’s Main Street, was adopted in 2006 (Elliot, Goebel, and Meadows 2012).

3. The latest versions of the FBC and the CZC were retrieved (that is, the latest version of Former Chapter 59 of the Revised Municipal Code that was replaced by the FBC) available online from the City of Denver (City of Denver 2010, 2014) and the citywide zoning maps for the CZC and FBC were obtained from city officials.

4. In the analysis of the CZC, the three Main Street zones included in the CZC were excluded. This approach was used to appropriately compare the FBC and the CZC given that these three Main Street zones were conceived as FBCs.

5. While the LEED-ND rating system differs from BREEAM Communities and DGNB-NSQ rating systems that are used in other countries, including the United Kingdom and Germany, in terms of certification process, certification types and specific thresholds for certification, key sustainable design criteria are similar across these rating systems.

6. Denver’s FBC and CZC include regulations for special cases including Master Planned Development, Planned Unit Developments (PUD), special area plans and overlay districts. These regulations for special cases were excluded from the analysis because their applicability is restricted to distinctive areas in Denver and because the findings are unlikely to provide useful insights for other municipalities.

7. Given that the rating system assigns more (or fewer) credit points to sub-criteria that it deems more (or less) important, the authors retained these credit points as weights to maintain the overall integrity of the rating system. However, for sub-criteria without defined points, the authors used the maximum achievable credit points for that specific criterion as the weight.

8. The three Main Street zone districts that were included in the CZC (as an amendment to the previous CZC) prior to adoption of the FBC are an exception to this general trend in the CZC.