ADU Fire Requirments

The Bureau of Fire Prevention works with ADU permit applicants to ensure compliance with the California Fire Code (CFC), which aims to ensure public health and safety. Fire staff can be reached at 408-535-7750.

Be sure to view our Reducing Fire Risks for ADUs webpage for important tips to protect your ADU property and occupants.

The information here focuses on ADU Fire requirements as also presented in the ADU Universal Checklist. Water company contact information for the required letter on Water Flow Data is also listed below.

1. Fire sprinklers - Is the primary residence protected by fire sprinklers?
   If yes, the ADU must have a fire sprinkler system.
   
   
2. Fire sprinklers and Attached ADUs - Is the project an Attached ADU greater than 500 square feet AND does the overall gross floor area with the main unit exceed 3,600 square feet?
   If yes, the entire house and ADU are required to be protected with a fire sprinkler system.
   
   
3. ADU Address - Are address numbers of both the main home and ADU visible and legible from the street?
   If "No," your plans will not be approved. Per CFC 505 regulations, emergency responders must be able to see both these address numbers. Your ADU will be provided with a unit number, which must be legible and visible from the street that fronts the property. In addition, you must place the unit number alongside the entry to the ADU. If you need to obtain an ADU address, please complete Form #302-Address Assignment Request.
   
   
4. ADU Access - Is the distance from the street curb of the lot to all portions of the proposed ADU no greater than 200 feet as measured along a minimum 3-foot clear path to all sides of the ADU?
   If “No,” your project may require a Fire Variance that entails additional safety measures. Contact Fire Permit staff at 408-535-7750 for direction.
   
   
5. Hydrant Proximity - Are all exterior walls of the ADU within 600 feet of a fire hydrant?
   If “No,” your project may require a Fire Variance that entails additional safety measures. Contact Fire Permit staff at 408-535-7750 for direction.
   
   
6. Hydrant Water Flow - Is a minimum flow of 1,000 gpm at 20 psi available from the closest hydrant?
   You must submit a letter from your Water Company that contains this water flow data with your building permit application. Instructions for contacting your Water Company are below.
   
   If the flow is other than 1,000 gpm at 20 psi, Fire staff will review flow data and will evaluate if additional fire safety measures are required. 

CONTACT YOUR WATER COMPANY FOR A LETTER ON WATER FLOW DATA

IMPORTANT:  Many projects get their permit issuance delayed because they have not provided this letter. Contact your water company today to get this letter -- it's easy!

Here are instructions for the required letter that provides data on the water flow and pressure at the hydrant/s closest to your lot.

Need to look up your water service provider? Use the Utility Services Lookup tool.

When emailing your request, place "ADU WATER FLOW REQUEST" in the subject line and present the following information:

• Requestor's name
• Street name and address of the project
• Nearest cross street to that location

Water Company Email Addresses

San Jose Water Company
Phone: 408-918-7362
Email: engineering.dept@sjwater.com - put "ADU Water Flow Request" in the subject line

Great Oaks Water Company
Phone: 408-227-9540
Email: customerservice@greatoakswater.com - put "ADU Water Flow Request" in the subject line

San Jose Municipal Water System
Phone: 408-277-3671
Use online Request Form:
https://www.sanjoseca.gov/Home/Components/FormBuilder/FormBuilder/55326bebeb634420ae7eb9efa868d577/3