Portland is home to thousands of significant historic resources ranging from parks to schools, residential districts to cultural landmarks. Many, but certainly not all, of the city’s significant historic resources have been designated on the National Register of Historic Places or on the City of Portland’s list of Historic and Conservation Landmarks. Designated historic resources are subject to regulatory protections outlined in the Portland Zoning Code, primarily Chapters 445 and 846. Because the Zoning Code can often be a complex source of information, the following page summarizes the regulatory protections that are most frequently applied to historic resources.
The Portland Zoning Code applies different preservation protections to historic resources based on designation type (e.g., a National Register resource is treated differently than a Conservation Landmark). This tiered system provides a menu of designation and regulation options based on the significance of the resource and the motivations of the property owner at the time of designation (Note that owner consent is required for a historic resource to be designated). In some cases, a resource may have more than one designation, such as a Conservation Landmark that is also listed in the National Register. In these cases, the regulations that apply to the “higher” designation are generally those that apply to the resource.
The handout, An Overview of Historic Resource Designations and Protections, provides a summary of the different types of historic resource designations and their accompanying protections. For more information on the specific application of historic resource protections, visit the Bureau of Development Services’ Historic Review webpage.
National Register Properties and Districts
The National Park Service designates buildings, districts, objects, sites, and structures on the National Register of Historic Places. Owner consent is required for individual property designation and majority implied consent is required for historic district designation. The National Register is the “highest” level of designation and, as such, generally comes with the most protections.
State rules require the City of Portland to review applications to demolish National Register resources that are individually listed or contributing to a historic district. Demolition Review requires a vote of the City Council before an application to demolish a National Register can be approved. To approve a demolition, the Council must find that an economic hardship exists and/or that the demolition would better meet the goals and policies of the Comprehensive Plan.
All National Register resources designated before February 2017 are subject to Historic Resource Review, a form of design review intended to protect the defining features of historic properties and districts. Historic Resource Review applies to alterations, additions, and new construction. The approval criteria used in Historic Resource Review are found in the Portland Zoning Code and/or design guidelines that have been adopted for several historic districts. In accordance with State rules, National Register resources designated after February 2017 can only have Historic Resource Review applied following a City hearing and adoption process.
Local Historic Landmarks and Districts
The City of Portland designates Historic Landmarks and Districts that are architecturally, culturally, and/or historically significant at the local, state, or national level. Owner consent is required for individual Historic Landmark designation and unanimous consent is required to create a Historic District (note that Portland currently has no local Historic Districts). State rules adopted in January 2017 allow cities to create historic districts with majority owner consent; however, revisions to Portland’s program are not expected until 2018.
Individually listed Historic Landmarks are subject to a 120-day demolition delay period but, unlike National Register resources, there is no local ability to deny demolition. Alterations to, additions to, and new construction on the site of Historic Landmarks are subject to Historic Resource Review. The Historic Resource Review approval criteria can be found in the Portland Zoning Code.
Moulton House, a Conservation Landmark that has been adaptively reused into six condominium units.
Local Conservation Landmarks and Districts
The City of Portland designates Conservation Landmarks and Districts that are architecturally, culturally, or historically significant at the local or neighborhood level. Owner consent is required for individual property designation and majority implied consent is required for historic district designation. State rules adopted in January 2017 allow cities to create conservation districts with majority owner consent; however, revisions to Portland’s program are not expected until 2018.
Individually listed Conservation Landmarks and contributing properties in Conservation Districts are subject to a 120-day demolition delay period. Alterations to, additions to, and new construction on the site of a Conservation Landmark or within a Conservation District are subject to Historic Resource Review. The Historic Resource Review approval criteria can be found in the Portland Zoning Code, however, most projects in Conservation Districts have the option of following clear and objective Community Design Standards as an alternative to Historic Resource Review.
Historic Resources Inventory (HRI)
The City of Portland conducted a citywide inventory of more than 5,000 potentially significant historic resources in 1984. The “HRI” is not a designation, but an evaluation of historic significance and likely eligibility for future designation. Resources on the Inventory fall into two categories: ranked and unranked. Ranked resources (rank I, II, and III) were found to have enough significance to be considered for designation. Unranked resources, while having distinctive qualities, were found to be lesser candidates for designation.
Ranked resources on the Inventory are subject to 120-day demolition delay. Unranked resources are not subject to any historic resource protections, but may be subject to a 35-day demolition delay applied to permits to demolish residential structures in residential zones.
Over 5,000 properties are included in the citywide Historic Resources Inventory. This 1893 North Portland home was determined to be a “rank II” and still stands today (1984 HRI photo).
Properties not Inventoried or Designated
There are properties citywide that are neither on the HRI nor designated, but may still be significant historic resources. The City of Portland does not apply historic resource protections to properties that have not been added to the Inventory or designated by the National Park Service or City. Residential structures in residential zones are, however, subject to a 35-day demolition delay period.
For information about designating a property as historic, visit the Individual Historic Resources and Landmarks page.