Public Improvements for Infill Lots

Oregon City Municipal Code (OCMC) 16.12.011 provides requirements for vacant lots of existing lots with existing residential structures who want to either build a new house or expand their existing house. A short summary of those requirements follows:


  • Compliance with OCMC 16.12.011 is required for new construction or additions which exceed 50% of the existing square footage of all 3- to 4-plexes, single- and 2-family dwellings living space. Garages, carports, sheds, and porches may not be included in the calculation if these spaces are not living spaces
  • Accessory dwelling units (ADU) are not subject to compliance with OCMC 16.12.011
  • All applicable 3- to 4-plexes, single- and 2-family dwellings shall provide any necessary dedications, easements or agreements as identified in the transportation system plan and OCMC 16.12


When applicable, the following public improvements are required with respect to street and/or right-of-way:

  • Improve street pavement, construct curbs, gutters, sidewalks and planter strips
  • Plant street trees

All required improvements are required to be engineered by a Professional Engineer licensed in the State of Oregon except for infill sidewalk that has no Americans with Disabilities Act (ADA) ramps unless grade, as determined by the City, requires engineered plans.

Also, if sewer and water are not readily available, those lines are required to be extended and do not count against the maximum cost of compliance.

Limitations for Infill Lots & Residential Structure Expansions

The cost of compliance with the standards identified in subsections 16.12.011.B.1 and 16.12.011.B.2 is calculated based on the square footage valuation from the state of Oregon Building Codes Division and limited to 10% of the total construction costs.

The value of the alterations and improvements is based on the total construction costs for a complete project rather than costs of various project component parts subject to individual building permits.

The entire proposed construction project cost includes engineering and consulting fees and construction costs. It does not include permit fees, recording fees, or any work associated with drafting or recording dedications or easements.

The value of public improvements can be calculated by staff or by a contractor or civil engineer which the City concurs with. When public improvements exceed 10%, City staff works with the applicant to determine the best resolution whether that be fewer improvements or a fee-in-lieu.


If the applicant believes the requirements within OCMC 16.12.011 are not appropriate for their proposed development, they may apply for a modification. Review the Public Improvement Modification page for more details.

It is strongly recommended to speak with staff prior to making an application to understand if the request is likely to get approved.