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Large Homes and Lots


Latest News

During the Sept. 10, 2019 City Council Study Session, council decided to not  take up the proposed Residential Estate (RE) and Residential Rural (RR) code amendments for further consideration, citing the Aug. 22, 2019 Planning Board recommendation, and the public feedback expressing opposition. The proposed ordinance will not be considered by City Council. Video of the Sept. 10, 2019 City Council discussion may be  viewed online , and additional information on the proposed ordinance may be found from search links on the  Planning Board webpage .

The proposed code amendments would have conditionally allowed one additional ADU and the conversion of existing homes to a duplex or triplex in the RE and RR zones. Council directed that the next City Council should look holistically at addressing the issue of large home redevelopment across the broader community next year - should the next council prioritize the project. 


City Council identified Large Homes and Lots as a priority item for Land Use Code updates in 2018. Council held two study sessions in September and December 2018, and received feedback from the public during a discussion about a potential emergency development regulation for large homes and lots – no action was taken and there is not a moratorium or emergency large home ordinance in effect at this time. The Planning Board also provided feedback on Nov. 15, 2018. The meeting can be viewed here. 

The Large Homes and Lots project includes the study of potential land use and energy-related regulatory tools to address large homes being constructed within the residential zoning districts of the city, including but not limited to the Residential – Estate (RE) and Residential – Rural (RR) zoning districts, that may be incompatible with the existing neighborhood character, and the city’s energy-efficiency and affordability goals. The project will explore regulations related to:

  • Form, bulk, and intensity standards of the Land Use Code.
  • Incentives or disincentives, to encourage the construction of smaller energy-efficient homes and/or the preservation of existing homes.
  • Creative infill standards to consider multiple smaller-units on large lots (where appropriate), including the subdivision of large lots into two or more smaller lots.

City Council held a  Study Session on May 28, 2019  directing staff to narrow the project scope for phase one, focused on conditionally allowing one additional Accessory Dwelling Unit (ADU) per lot, and the option to conditionally convert an existing single-family dwelling unit to a duplex or triplex unit, within the RE and RR zoning districts.  Council did not request a cap on floor area or home size, and other residential options could be pursued as a phase two at a later time.   Read the staff memo  and  view the study session  for more information.

A proposed ordinance was then drafted in Q3 of 2019 to conditionally allow one additional Accessory Dwelling Unit (ADU) on a given lot (two total ADUs per lot), and to conditionally allow the conversion of existing detached dwelling units into duplex or triplex units in the Residential Estate (RE) and the Residential Rural (RR) zoning districts. The proposed changes were intended to align with the direction received from City Council on May 28, 2019, and with the Boulder Valley Comprehensive Plan (BVCP) goals and policies for increased housing diversity and capacity, as well as enabling more affordable housing options. The proposed ordinance was considered by Planning Board on August 22, 2019, where a public hearing was conducted. Read the Aug. 22 Planning Board packet . Planning Board did not recommend approval of the proposed ordinances, instead recommending to council that a broader more comprehensive approach be taken. View the Aug. 22 Planning Board minutes.  


The preliminary goals of the project were to  study and consider :

  1. Creative solutions to potentially allow infill redevelopment of large lots into two or more houses / units – additional units may be allowed where appropriate, provided they are more affordable and designed in such a way as to be sensitive to the neighborhood context.
  2. Potential hard cap on floor area for single family residential development.
  3. Incentives / disincentives for preserving existing housing stock, and creative infill solutions that are also affordable.
  4. Potential strategies and phasing for adjusting the Land Use Code’s size, form and bulk compatibility standards.
  5. Updates to the city Energy Conservation Code to accelerate the city’s energy conservation goals.

For questions on the project please contact Andrew Collins at  [email protected]  or Karl Guiler at  [email protected]

Why and Purpose

The city’s residential neighborhoods are experiencing a dramatic demographic and economic shift with the replacement of modest more-affordable homes with larger more-expensive homes. These large homes are often inconsistent with the existing character of the neighborhoods, and are an inefficient use of land that has exacerbated the city’s housing / jobs imbalance and the high-cost of housing. In addition, large homes do not align with the city’s energy-conservation goals and policies as they consume greater amounts of energy, both in operation and construction, than do modest-sized homes. To address these shortcomings, smaller home sizes and creative infill solutions that consider the potential for multiple smaller-homes in large lot areas (where appropriate), should be encouraged to foster a more efficient use of land, energy and resources, and to support a broader housing and economic diversity in the city’s residential neighborhoods.

Consistent with newly updated Boulder Valley Comprehensive Plan (BVCP) policies (see below), staff will amend the Land Use Code to require smaller homes in residential zones that are consistent with the character of the existing neighborhoods, and that advance the city’s energy-efficiency, climate sustainability, and housing affordability goals and policies. This includes creative solutions for both the preservation of existing homes and the development of more small houses (rather than fewer large houses) in residential zones.

How could this affect my property?

Depending on recommendations and the public’s input, potential changes may include adjustments to the permitted new home size and floor area regulations. It may also provide creative regulations to permits more smaller homes and potentially additional housing types. In addition, incentives and Energy Conservation Code updates are also possibilities to encourage more smaller homes. Please note that there is not a moratorium or emergency large home ordinance in effect at this time. The existing regulations continue to apply, and any legally existing use or structure may continue to be legally maintained and operated as prescribed by the Land Use Code.

Process and Engagement

Engagement activities will kick-off in early 2019 where community members will be able to share their feedback by participating in events and online. Community feedback will be presented to City Council and will help inform recommendations from city staff. The Project and recommendations are anticipated to conclude by during the Fall of 2019.

Additional Information



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