ADUs in Temecula


ADU stands for Attached Residential Dwelling. It is also known as a Granny Flat, Mother-in-Law’s Quarters, or a Second Dwelling. It can be an attached or detached independent living facility, for one or more person(s) and is located on a lot with an existing or proposed primary residence. It will include permanent provisions for cooking, eating, bathing, sleeping and living on the same parcel as the single-family or multifamily dwelling is or will be situated.

Temecula Municipal Code outlines the ADU Requirements in the following chapters:

For properties that have septic: Septic capacity for your ADU needs to be adequate. You can determine this by consulting with Riverside County Environmental Health Department.

There are many factors when submitting an ADU. Factors such as location and size of the ADU.

Submittal requirements are outlined in the Temecula Municipal Code Chapter 17.23.030 – Zoning – ADU – Projects exempt-Building permit approval only. The ADU needs to meet these requirements. Then you can submit directly to the Building and Safety Division (once all minimum submittal requirements are met).

An ADU Application must be submitted to the Planning Department, for any ADUs that do not meet the above building permit only requirements.

Various factors contribute to an ADU’s permit cost. Factors such as:

  • Fire Sprinkler Fees (if applicable)
  • PLAN CHECK FEES – Building and Safety plan check and inspection fees
  • BUILDING & PLANNINGWhether or not the ADU is a building permit only or planning application ADU
  • GRADING COSTSDoes the ADU require grading? (determined by the Public Works Department)
  • SIZE IMPACT FEES – Depending on the size of the ADU, there may or may not be certain impact fees under certain circumstances. (These details are outlined in Temecula Municipal Code Chapter 17.23.060)