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BPC-013 Third Party Plan Check

Permit and Resource Management Department Banner 750

Version 07/01/2024


An applicant may choose to use a third-party building plan check (TPPC) consultant to reduce building plan review processing time.

Partial building permits may be authorized for this process provided all subsequent building permits that are physically attached to the structure authorized by the partial building permit, also go through this process. One example is a foundation-only permit followed by the structure.


  1. The applicant shall submit a building permit application to Permit Sonoma including a file of the complete building plans and separate files of related documents, such as soils report, structural calculations, energy calculations, green building documentation, etc… Only complete submittals will be accepted.
  2. All building, property line, well, water system, septic system locations and setbacks must be clearly dimensioned on submitted plans in conformance with CSS-019 Minimum Standard Site Plan Requirements for Building & Engineering Applications. Where property lines are in question, a survey may be required to ensure submitted site plans are accurate.
  3. The applicant shall complete and upload the following BPC-018 Third Party Plan Check Notification (PDF) to Permit Sonoma before or with the building permit application.
  4. The applicant shall select a consultant from the list of Permit Sonoma’s BPC-019 Third Party Plan Check Approved Consultants. The applicant is responsible for payment of costs to the consultant which are in addition to Permit Sonoma’s building plan check fees.
  5. The applicant shall submit a project specific soils report in all cases where required by Technical Bulletin B-28. The soils report shall meet the investigation and reporting requirements of the California Building Code (CBC) Chapter 18, and the geotechnical engineer of record shall verify that all applicable recommendations have been adhered to in the project plans, specifications, and details. Permit Sonoma will conduct a site review to assist in determining if a soils report may be waived if one is not provided with the initial submittal.
  6. Reviews from ancillary review disciplines (other than Building Plan Check) will be conducted in parallel with the Building Plan Check review conducted by the TPPC agency. At the time of TPPC authorization, the disciplines with outstanding reviews will be identified on the BPC-018 Third Party Plan Check Notification (PDF). All requirements for approval shall be communicated by the applicant to the TPPC agency, and corresponding plan and document changes shall be incorporated into the plans and supporting documents being reviewed by the TPPC agency for code compliance. Upon resubmittal, an adequate response shall be provided to each identified issue or condition of approval.
  7. At the time of the Building Plan Check Division authorization of the TPPC, the BPC-018 form will be completed and provided to the applicant. Once this document is provided to the TPPC consultant, the TPPC consultant will contact the Permit Sonoma Customer Service Division via email:

    to have the TPPC consultant’s account added to the specific Building Permit application record. This will allow the upload of reviewed plans, supporting documents, and the required transmittal document once the application review for conformance to applicable codes has been completed and all ancillary divisions have approved the application for issuance.

  8. Projects requiring additional permits (Grading, Septic, Well, Use, etc...) need to have the associated permit applications submitted, approved, and/or issued (as identified by the affected division) for each additional required permit prior to final approval from the TPPC agency.
  9. Projects subject to the flood plain ordinance (Chapter 7B, Sonoma County Code), located within the Alquist Priolo Zone, or projects with active code violations will have the appropriate requirements noted by each applicable review discipline and communicated with the applicant. Applications requiring concealed construction verification of elements constructed without permitting or inspections shall include a concealed construction plan, in accordance with the Permit Sonoma Concealed Construction Verification Guidelines. The applicant will be responsible for communicating these additional design and justification requirements with the TPPC agency.
  10. Once all reviews by affected secondary disciplines have been completed and additional applications are submitted as needed, the TPPC will be authorized by the Building Plan Check Division. The Permit Sonoma Building Plan Check fees for a TPPC are reduced by 25% once the TPPC has been authorized.
  11. Permit Sonoma will assign the TPPC project to the Building Check customer service cubicle, and the Building Plans Examiner (BPE) assigned to this cubicle on any given day will answer any questions relating to status, applicable code requirements, or additional approvals required by other divisions.
  12. The applicant shall submit building plans and all related supporting documents directly to the TPPC agency.
  13. Any requests for code and/or policy interpretations by Permit Sonoma to clarify if the plans and supporting documents adequately demonstrates and justifies code compliance, either by the applicant or the TPPC agency, shall be directed to the BPE as soon as possible. The expectation is for the applicant and consultant to resolve issues, however, there may be instances where Permit Sonoma can assist on providing interpretations of specific code sections or specific justification and documentation requirements.
  14. Upon completion of the plan review process, the consultant shall upload the following to the Building Permit application’s Digital Plan Room:
    1. A letter of approval from the consultant with a brief analysis of how the plans and supporting documents adequately demonstrate compliance with the applicable codes and standards the application is being reviewed under. The letter should highlight if an accessibility hardship application (per CBC Section 11B-202.4) was required and approved. The letter should also address any required deferred submittals and any partial or additional permits that will be required to complete the scope of work included in the applicable permit application;
    2. All resubmittal correspondences, plan check comments and responses;
    3. The final plan set file and separate files of related documents;
    4. All sheets of plans and the cover sheet of other documents shall be stamped and signed as reviewed for code compliance by the consultant; and
    5. All issues identified by Building Plan Check and other review disciplines shall be provided with an applicable response adequately addressing the specific issue.
  15. Permit Sonoma will process the project for Building Plan Check Division approval within approximately three (3) business days from the date that the third party approved documents (As outlined per Item M) have been uploaded and all previously outstanding review disciplines’ approvals have been obtained. Prior to building permit issuance the BPE shall ensure the plans are consistent with the applicable adopted codes and Permit Sonoma policies and ensure that the project has the appropriate Permit Sonoma section clearances and/or associated permits are issued (if required prior to section approvals). Absent any inconsistency with adopted code requirements or any outstanding section clearances and/or issued permits, Permit Sonoma will issue the building permit, after final fee invoicing by a Permit Technician and subsequent payment by the applicant.
  16. All subsequent field plan changes, structural revisions, changes to scope, and deferred submittal items related to the approved plans that have gone through the TPPC shall also be reviewed through the TPPC process. Deferred submittal applications and revision applications which do not alter the floor plan, use, structure location, valuation, or other elements which may affect secondary divisional approvals may be applied for with the appropriate documentation outlined in item “M” above and will be reviewed by Building Plan Check staff, typically within 3 to 5 business days.
  17. If a proposed revision changes the scope of work or building location or requires review by any division other than Building Plan Check, the applicant shall coordinate with a Permit Technician for adjustment of project valuation and fees and coordinate initial routing to all affected divisions, prior to the re-authorization of Third Party review by the Building Plan Check staff. The review and routing process for revision applications will be similar to the process for new applications, starting with item “F” above.