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PJR-114 Design Review for Historic Resources

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The Board of Supervisors adopted the design review process for historic resources process to preserve the County’s unique and irreplaceable structures and sites that have significant historic, architectural, or aesthetic interest. This process is intended to ensure that exterior alterations, additions, new construction, and relocation of structures involving historic resources or sites are conducted in a way that preserves the significance of the resource and the character of any historic district in which it is located. 


When is Landmarks Commission Design Review Required?

The level of Landmarks Commission Design Review varies based on the scope of the project. All projects must be consistent with applicable policies of the General Plan, specific or area plans, and the Zoning Ordinance. 

Ministerial Permits

For ministerial permits (i.e., building and demolition permits), design review is required if the project site is a designated County Landmark or has Historic District (HD) Zoning. There are two types of projects that staff can review and approve:

  1. Replacement in kind. Building permit clearance for projects consisting of “replacement in kind” using the same materials and colors in the same location. Foundation repairs, re-siding, re-roofing, replacement/repair of windows using the historical window type are examples of projects that staff can approve with no additional plans or applications beyond the building permit submittal. An  Administrative Design Review application is required for documentation purposes. 
  2. Minor alterations in a Historic District with guidelines. Staff can also approve minor alterations when in conformance with  HD Guidelines. An application for Landmarks Commission Design Review is required. If there is any question on whether the alteration is considered minor, staff will schedule the item as a “Consent” item for the next Landmarks Commission meeting. If the Commission determines the item should be brought back on the regular calendar, an additional processing fee will be charged for Commission approval.

Discretionary Permits

For discretionary permits (i.e., use permits), design review is required. A referral to the Landmarks Commission is required if the project site is a designated County Landmark, has Historic District (HD) Zoning, is in the Historic Resource Inventory indicating that it is potentially eligible for historic designation, or there is other evidence that it could be eligible for historic designation. The referral to the Commission is to determine if a Historic Resource Survey or Evaluation is required, and/or if the project requires review and recommendation at a Landmarks Commission meeting. 

In the case of discretionary permits, the Landmarks Commission acts in an advisory role to the decision-making body authorized to approve the permit, such as the Board of Zoning Adjustments. A joint session of the Landmarks Commission and Design Review Committee will be required for commercial projects involving major alterations or new construction. Some residential development projects that include significant site planning may also require review by both the Landmarks Commission and Design Review Committee. 

Application Submittal

A project proponent submits a complete application to Permit Sonoma’s Planning Division, including all required plans and materials, and filing fees. A planner is assigned to the project, and the application reviewed for completeness within thirty days. The project proponent is notified in writing if the application is found to be incomplete and what information must be submitted to complete the application. Incomplete means that either all information required was not submitted or some of that information was found inadequate. After the application is determined to be complete, the assigned planner may refer the application to other Permit Sonoma departments and appropriate outside agencies for review, comment, and conditions. 

Environmental Review

Projects involving historical resources are subject to the California Environmental Quality Act (CEQA) and environmental review is required unless the Department can apply an exemption to the proposed project. The Secretary of the Interior’s Standards for the Treatment of Historic Properties are nationally accepted standards for preservation, rehabilitation, restoration and reconstruction of projects that affect historic properties and districts. Projects that meet these standards are typically categorically exempt from CEQA. The majority of the projects reviewed by the Landmarks Commission qualify for a categorical exemption. Projects that are not specifically exempt from CEQA may require additional fees and studies to complete the environmental analysis and prepare the required documents

Application Review

Staff Approval Process

The assigned planner will evaluate the project proposal for consistency with all applicable standards and policies. Upon completion of the project review, the planner may approve the project. 

Landmarks Commission Hearing Process

If the project scope of work exceeds what can be approved at the staff level, the project must be reviewed by the Landmarks Commission. The project proponent submits a complete Landmarks Commission Design Review application. The deadline for submitting for the monthly meetings is three weeks prior to the meeting date.

In the case of a demolition of an historic structure, the demolition permit may be suspended for up to 6 months in order to evaluate alternatives to demolition, but may not be denied by the Landmarks Commission. The Landmarks Commission reviews the design of the proposed project at a meeting and may approve, approve with conditions or deny the project.

The Commission holds regular public meetings as needed on the first Tuesday of each month. A 10-day notice of the public meeting is provided for all projects located within any of the County’s Historic Districts. All interested persons have an opportunity to comment on the proposed project at the meeting. Landmarks Commission approval must be obtained, and all conditions must be met, before any building permits may be issued. The decision of the Landmarks Commission is appealable to the Planning Commission. Appeals must be submitted within ten calendar days of the date of the Landmarks Commission action. 

Conceptual Design Review

When design review is required, applicants are encouraged to meet with the Landmarks Commission staff for early input on proposed alterations prior to submitting the formal Design Review application. For more complex projects or major alterations, applicants are encouraged to get early input from the Landmarks Commission as a “Conceptual Design Review” item. The minimum submittal requirements are:

  1. Planning Application PJR-001(PDF)
  2. Cover letter with project description
  3. Current site photos
  4. Any existing historical records or photos beyond what Permit Sonoma may have
  5. Existing and proposed site plan
  6. Conceptual elevations
  7. Proposed materials & colors

For Conceptual Design Review, staff analysis is limited to a cover page referencing relevant criteria. Comments given at Conceptual Design Review are non-binding and do not constitute an approval.

Standards and Criteria

The Landmarks Commission has adopted guidelines related to the alteration, relocation or demolition of existing designated (local, state or federal) historic structures, and for the construction of new structures on properties with Historic District (HD) zoning or on the same property as designated historic structures. The following guidelines should be reviewed by property owners prior to submitting a Design Review application for historic resources.

Required Application Materials

A complete application shall include the following items. Incomplete applications will not be accepted. Note: All documents must be submitted electronically. Permit Sonoma staff may, upon request, provide some assistance with electronic submittal if required.

  1. Application Forms:
    1. PJR-001 Planning Application(PDF), signed by the applicant and property owner(s).
    2. PJR-011 Indemnification Agreement (PDF), signed by owner or agent with owner’s written authorization. A separate indemnification agreement must be signed by each property owner.
    3. PJR-095 At-Cost Agreement (PDF). Design review projects that require Landmarks Commission review are processed on an at-cost basis. An At-Cost Agreement is required at the time of submittal to provide a minimum fee and deposit sufficient to cover the cost of staff work on the project. Deposits must be maintained to cover staff costs or work may be halted on the project.
  2. Proposal statement, describing in detail the following:
    1. Current and proposed use of the property
    2. Existing structures and their uses including year built and condition
    3. Historic district in which the property is located, if applicable
    4. All proposed changes to existing buildings including additions, alterations, colors and materials
    5. All proposed new building(s) and site improvements
    6. Discussion of how the proposed project complies with the standards and criteria, above 
  3. Site plan meeting the requirements of PJR-129, Site Plan Requirements for Planning Applications
  4. Preliminary Building Plans including elevations, floor plans, and cross-sections. All rooms must be labeled and include built-in fixtures. Elevations must identify exterior colors and materials. Structural plans are not required until application is made for building permits.
  5. Preliminary Site Grading Plans distinguishing between areas of cut and areas of fill. Note: not all projects will require grading plans. Please check with the Engineering Division of Permit Sonoma. 
  6. Preliminary Landscaping Plans showing location, species, common name, and size of plants to be planted. Landscaping should be compliant with the Water-Efficient Landscaping Ordinance (WELO) in Section 7D3 of Sonoma County Code. 
  7. Preliminary Lighting Plans. Provide the manufacturer’s specification sheet for each light fixture proposed for the exterior of the building(s) and the site. Include the location of fixtures on a site plan, floor plan, or elevations. 
  8. Tree protection plan. If any trees will be impacted by development or are proposed for removal, provide a site plan depicting all trees to be removed identifying diameter (in inches) and species type. Mitigation may be required by the Sonoma County Tree Protection Ordinance (Section 26-88-010(m))
  9. Historic Resource Evaluation prepared by an architectural historian or other qualified professional. Please note that a Historic Resource Evaluation is NOT required for structures located within a Historic District that have been identified as “non-contributing” by the applicable Historic District Design Guidelines. Refer to Guideline appendices for a list of non-contributing properties. Historic Resource Evaluations are still required for designated landmarks outside of Historic Districts. The evaluation must be submitted on State Historical Resource Inventory forms (DPR 523A and 523B) and must include the following minimum information: 
    1. Description of the property as it appears today and as it appeared historically.
    2. Date of construction, architectural style, distinguishing architectural features, exterior construction materials, type of roof, etc.
    3. Analysis of integrity with respect to the historic structure’s location, setting, design, materials, workmanship, feeling, and association.
    4. A statement of significance which provides specific information about the historic events, persons, architecture, etc., that make the property significant. The statement of significance must also explain why the resource is important in relation to its historic context and identify the specific physical characteristics that convey its significance. The historic function of the property, the historic themes represented by the property, and the period of time when the property played a significant role or acquired significance, must also be included.
    5. Identify all structures on the property as contributing or non-contributing depending on whether or not they relate to the significance of the property and identify any significant landscape features.
  10. Materials and Color Chart providing material and colors details for all exterior building materials. Include proposed paint and finish as appropriate. Include color photographs of the materials. Building materials should generally be low- to non-reflective.
  11. Photographs and Key Map. Provide photographs of the site, existing structures, and surrounding area. Photographs should be depicted on a key map with the location and direction in which the view was taken. Photographs should be taken from appropriate public road locations from which the proposed development may be visible.
  12. Filing fee. See the current Permit Sonoma Project Review Fee Schedule. Fees will be determined once the full scope of a project is evaluated by Permit Sonoma staff at the time of application submittal. If paying by check, please do not fill in amounts on checks prior to application acceptance.