Pre-Designed Accessory Dwelling Units


The cities of Arroyo Grande, Atascadero, Grover Beach, and Morro Bay obtained grant funding as joint applicant to hire a consultant and create a pre-approved Accessory Dwelling Unit (ADU) plan program. The goal of this joint effort is to expedite the ADU permitting process and encourage the construction of accessory units to support our regional housing goals. This page lays out the options and process for using the pre-designed plans.

For additional information regarding by-right ADUs please refer to the California ADU Handbook and the City Ordinance

Unit Options

The unit sizes range from a 316 square foot studio to a 1,007 square foot two-bedroom unit and are available in four different architectural styles, shown below. 

Unit1Plan sets for each of the six unit sizes can be viewed by clicking the links at the bottom of the page.

How to Begin

  1. Choose a size and architectural style for the ADU. Some things to take into consideration:
    1. Complementary architectural styles and materials are encouraged
    2. By-right ADUs allow for a reduced setback minimum of four (4) feet from property line 
  2. Submit a building permit application via the City’s online Permit Portal. The application shall include: 
    1. Signed Liability Waiver for release of construction plans
    2. Payment of the plan review fee 
    3. Stormwater documentation: Stormwater Plan application, PCR Waiver Request Form, and Water Pollution Control Plan
  3. Staff will then email the applicant a link to the construction plans
  4. Once the plans are received, the applicant can update the Project Information section of the cover sheet, check the appropriate boxes for optional design choices, and insert a site plan of the property. The site plan shall include:
    1. Dimensioned property lines
    2. Footprint of ADU
    3. Distances from ADU to property lines and other structures on the property
    4. Utility connections
    5. Erosion control plan
    6. Easements
  5. Upload the plans to the Permit Portal with the items from Step 4 completed for staff review. When site plan review is complete the building permit is ready to issue!     


Efficiency Unit: Not For Construction Plan Set