• Welcome to the new and improved Building Code Forum. We appreciate you being here and hope that you are getting the information that you need concerning all codes of the building trades. This is a free forum to the public due to the generosity of the Sawhorses, Corporate Supporters and Supporters who have upgraded their accounts. If you would like to have improved access to the forum please upgrade to Sawhorse by first logging in then clicking here: Upgrades

Is there a minimum size kitchen for an ADU in California?

gbfredly

Member
Joined
Apr 16, 2012
Messages
12
Is there a min. size kitchen for an ADU in California?
Junior ADU's are required to be Efficiency Kitchens( Health & Safety Code 17958.1).
However, I cannot find any minimum requirements, and my client wants the minimum.

I am proposing a 5 wide linear kitchen with the following:
A. Built-in 12" wide induction cook top (no oven and no microwave)
B. Kitchen sink 18"x18" x8" (no dishwasher or garbage disposal)
C. Undercounter refrigerator (no freezer)
D. Counter work space is about 24"w x 24" d (above the centered refrigerator)
D. Cabinets are lowers only on either side of the refrigerator.

Any experience with this out there?
 
California Residential Code:

R304.1 Minimum area. Habitable rooms shall have a floor area of not less than 70 square feet.
Exception: Kitchens.

R304.2 Minimum dimensions. Habitable rooms shall be not less than 7 feet in any horizontal dimension.
Exceptions: 1. Kitchens.
 
“Efficiency kitchen” defined.
“Efficiency kitchen” means a ... kitchen that contains a sink with a maximum [vertical] waste line diameter of 1.5 inches; appliances that do not require electrical service greater than 120 volts, or natural or propane gas; a limited food preparation counter; and storage cabinets. The entire kitchen shall not exceed six lineal feet, except that if existing counter space is being converted to efficiency kitchen use then the counter space shall not exceed eight lineal feet. [Examples of prohibited cooking appliances are: ranges, stoves, cook tops, and built-in ovens. Examples of cooking appliances that may be used are: microwave ovens, hot plates, and similar appliances intended for use on top of a countertop. Refrigerator size is not limited.] CA Health & Safety Code 17958.1
 
Is there a min. size kitchen for an ADU in California?
Junior ADU's are required to be Efficiency Kitchens( Health & Safety Code 17958.1).
However, I cannot find any minimum requirements, and my client wants the minimum.

I am proposing a 5 wide linear kitchen with the following:
A. Built-in 12" wide induction cook top (no oven and no microwave)
B. Kitchen sink 18"x18" x8" (no dishwasher or garbage disposal)
C. Undercounter refrigerator (no freezer)
D. Counter work space is about 24"w x 24" d (above the centered refrigerator)
D. Cabinets are lowers only on either side of the refrigerator.

Any experience with this out there?
 
Is there a min. size kitchen for an ADU in California?
Junior ADU's are required to be Efficiency Kitchens( Health & Safety Code 17958.1).
However, I cannot find any minimum requirements, and my client wants the minimum.

I am proposing a 5 wide linear kitchen with the following:
A. Built-in 12" wide induction cook top (no oven and no microwave)
B. Kitchen sink 18"x18" x8" (no dishwasher or garbage disposal)
C. Undercounter refrigerator (no freezer)
D. Counter work space is about 24"w x 24" d (above the centered refrigerator)
D. Cabinets are lowers only on either side of the refrigerator.

Any experience with this out there?
Update:
I met with the City Plan-checker and he had no size requirements. The only requirements stipulated were:
1. Cooking device (with an exhaust vent or “UL listed” fan with charcoal filter)
2. Refrigerator
3. Sink (with hot & cold water)
So, the proposed 5’ wide kitchen without upper cabinets was ok with the Plan-Checker.
 
with an exhaust vent or “UL listed” fan with charcoal filter
Could you get a code section number for that?.....most plan check correction sheets have the code sections listed. Oh and the refrigerator too.
 
Could you get a code section number for that?.....most plan check correction sheets have the code sections listed. Oh and the refrigerator too.
2022 CRC R202 KITCHEN. An area used, or designated to be used, for the preparation of food.

2022 CRCR306.2 Kitchen
Each dwelling unit shall be provided with a kitchen area and every kitchen area shall be provided with a sink.

2023 CA Government Code 65852.22.
6)... accessory dwelling unit to include an efficiency kitchen, which shall include all of the following:
(A) A sink with a maximum waste line diameter of 1.5 inches.
(B) (A) A cooking facility with appliances that do not require electrical service greater than 120 volts, or natural or propane gas. appliances.
(C) (B) A food preparation counter and storage cabinets that are of reasonable size in relation to the size of the ...accessory dwelling unit.
 
(B) (A) A cooking facility with appliances that do not require electrical service greater than 120 volts, or natural or propane gas. appliances.
(C) (B) A food preparation counter and storage cabinets that are of reasonable size in relation to the size of the ...accessory dwelling unit.
So they don't allow a 240V range?
 
2022 CRC R202 KITCHEN. An area used, or designated to be used, for the preparation of food.

2022 CRCR306.2 Kitchen
Each dwelling unit shall be provided with a kitchen area and every kitchen area shall be provided with a sink.

2023 CA Government Code 65852.22.
6)... accessory dwelling unit to include an efficiency kitchen, which shall include all of the following:
(A) A sink with a maximum waste line diameter of 1.5 inches.
(B) (A) A cooking facility with appliances that do not require electrical service greater than 120 volts, or natural or propane gas. appliances.
(C) (B) A food preparation counter and storage cabinets that are of reasonable size in relation to the size of the ...accessory dwelling unit.
The lines in red above abut 1.5" max drains and 120 volt max appliances are not found in CGC 65852.22.6.
https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=GOV&sectionNum=65852.22.

1683833275630.png
 
CBC 202 defines a kitchen or kitchenette as a room, space or area with equipment for the preparation and cooking of food.
I've not found anything that defines "cooking", but in a number of discussion through the years, an informal consensus emerged that a cooking appliance conducts heat directly onto food. In other words, a microwave does not apply heat to the food, so it is not a cooking device. A single hot plate is a cooking device. An induction cooktop in conjunction with the right pans makes the pan bottom into a cooking device. A convection oven might be a cooking device, because it also happens to heat the metal tray upon which the food sits.

I do not claim this is any official definition, and somebody can probably shoot holes in this area.

In post #1, I believe the 5' kitchen has 2 appliances (cooktop and refrigerator), and it describes some storage, so it should qualify.

here's the smallest kitchenette I've found over the years, 30" wide. Add a shelf above for storing food, and it should work for a junior ADU:

CK3016.jpg


https://www.ajmadison.com/cgi-bin/ajmadison/CK3016.html
 
Top