• All submittals for pre-approval of ADU plan shall be reviewed for compliance with the City’s ADU Ordinance, State ADU Law, and state and local Building Standards Code regulations. Changes to these regulations after the City has granted pre-approval may require re-submittal of the pre-approved plans.
• All submittals are required to pay applicable permit fees that would otherwise apply to an application for an ADU of the same size as that contained in the proposed plan for pre-approval, as specified below. 
• All pre-approved plans will be posted on the City's website for public viewing, along with the applicant/designer's contact information. The City does not guarantee, nor is it responsible for, the accuracy of the contact information. 
• If a customer chooses to use a set of pre-approved plans, they must first enter into a written contract directly with the applicant/designer. The permit application submitted by said customer must include the applicant/designer’s permission letter or other written authorization, and a copy of the signed contract with the applicant/designer, as part of their building permit application package. 
• All applications for ADU Plan Pre-Approval will be reviewed in accordance with Government Code section 66314 et seq. (State ADU Law) and the City’s ADU Ordinance under Title 10, Chapter 2, Part III, Article 5 of the Municipal Code, and shall comply with all applicable provisions under such authorities. 

The applicant/designer must prepare a complete set of plans and structural calculations for the design the applicant is seeking to be pre-approved. Plans and calculations must be prepared pursuant to the City’s Submittal Requirements. In addition to standard design documents, the plans and calculations shall comply with the following: 

• Design for worst-case scenario wind and seismic  in Walnut Creek.
• Design foundation based on soil bearing values of not more than 1500 psf of vertical soil bearing value and 100 psf of lateral soil bearing value.
• Indicate on the cover sheet of the plans that the project site shall have slopes of no more than 5% and the project site shall not be in a flood zone.
• Energy calculations and Title-24 compliance for any orientation.
• Solar PV is required for ADUs larger than 650 square feet. Indicate on the cover sheet of the plans, “Solar PV design to be submitted  under separate permit ”.
• Specify roof framing size and spacing if stick framing is used. No deferred roof truss submittal is allowed.
• Specify on plans whether a subpanel or a main panel with 225 amp busbar rating is proposed for the ADU. When a subpanel is proposed, indicate on plan the electrical panel of the main house is required to be upgraded with minimum 225 amp busbar rating, and a separate building  permit is required for such main panel upgrade.  
• Alternate details for fire-rated walls and rated or blocked eave projections  where ADU is between 4 feet and 5 feet from a property line or an imaginary property line between the primary residence and ADU.
• ADU over 800 square feet must comply with the requirements of Zoning Ordinance Section 10-2.3.504(A), including maximum floor area (up to 1,000 square feet), architectural consistency with the main building (e.g., matching exterior siding and trim, roof form, pitch and materials, and windows), and additional limitations for hillside lots (average slope of 15 percent or greater). Please note that due to the complexity of these regulations, pre-approved plans for an ADU over 800 square feet will likely not be applicable for many lots in Walnut Creek, unless they include multiple variations. 
• Maximum height of ADUs is 16 feet for most area of the city, except where specified in Zoning Ordinance Section 10-2.3.504(A)(3).

Submit the plans and calculations to the City for plan review electronically by visiting the Applying for a Building Permit webpage. Indicate ”Request Pre-approved ADU Review” at the beginning  of the project description. 

The applicant/designer is required to pay standard plan check fees and respond to plan check comments until all comments have been addressed. The standard plan check fees are calculated based on the ICC construction cost table as modified by the City. Plan check turnaround time is 23 days for the first review, and 18 days for subsequent rechecks. 

As described in the General Requirements section above, once the plans are approved, the City will post them with applicant/designer contact information on the City's website which can be used by authorized homeowners for permit applications within the same California Building Standards Code cycle.

The city will remove a pre-approved ADU plans from its website within 30 days of receiving a request for removal from the applicant for pre-approval (i.e., the designer).

Pre-approved plans only remain valid within the California Building Standards Code cycle under which they ae approved. Once a new code cycle starts (typically every 3 years), all pre-approved plans and applicant/designer contact information will be removed from the program and City's website. If an applicant/designer wishes to have their plans reposted after a code change, they must update their plans to comply with the new code requirements and go through the full pre-approval process again. This includes resubmitting the updated plans for plan review, paying full plan check fees, and meeting all other requirements of the pre-approval program.

Designers are responsible for responding to customer inquiries regarding their plans, constructability, and design changes or revisions during the permit application process and construction of the ADU. If a designer is unresponsive to such inquiries, their pre-approved plans and contact information will be removed from the program and City's website .

Any posting of preapproved ADU plans shall not be considered an endorsement of the applicant/designer and the quality of their work, or approval of the applicant/designer’s application for a detached   accessory dwelling unit by the City.  The City is not responsible for the accuracy of applicant/designer contact information or the sufficiency of any authorization necessary to use a pre-approved plan prepared by another individual or entity, or any liability resulting therefrom.