what is Accessory Dwelling Unit

What is Accessory Dwelling Unit

What does Accessory Dwelling Unit mean?

Accessory Dwelling Unit, or ADU.  is a separate dwelling that’s on the same piece of land as a single-family house or a multifamily residential property.

They are also known as granny flats, in-law suites.

ADU’s are allowed on single family properties where you can carve some space from the existing house footprint to create a unit.

Accessory dwelling units can also be a fantastic opportunity to create extra housing in our housing strapped landscape, as well as provide you with an opportunity to create income and cash flow without having to buy a whole separate property.

In this article we will discuss about Accessory dwelling units, rules & regulations in California.

In September 2021, Governor Gavin Newsom signed Senate Bill Nine (SB Nine), also referred to as the Home Act.

This law went into effect on January 1, 2022, and is making it possible in many parts of California to allow for subdivisions and creation of additional units were originally zoned for single family residence.

This might be subject to some restrictions depending on the city or county that you live in.

According to Charles Green (Owner & Founder of AS Architecture and Development) who has worked extensively in California and Oregon, the recently passed bill Senate Bill 9 and other bills that have been passed in the past couple of years are really bringing ADUs online and increase California housing.

Why are ADUs so popular?

ADUs get quicker approvals, this makes it faster to build and move in or rent out.  These ADUs can be used for personal use or can be rented out. In most of the cities Accessory dwelling units do not require additional parking spaces and has reduced impact on the city development fees.  This makes ADUs a popular choice.

To summarize ADU benefits-

Faster Permitting Process -Ministerial Approval from Local City or Jurisdiction makes the process easy and fast.
Single Family Residences are allowed to add 1 Accessory Dwelling Unit and 1 Junior ADU.
Existing Multi-family Properties are allowed 2 ADUs (attached or detached). May vary by city.
May be used for personal use or as a rental unit.
No or Reduced City Impact Development fees.
No Additional Parking Spaces Required (in most cities).

NOTE- Accessory Dwelling Units and Junior ADUs are prohibited to be sold separately from primary residence.

What are the size requirements of ADU’s?

According to California law following are the Accessory dwelling units size requirements.

Maximum Height – 16 feet

Distance from Property Lines- 4 Feet

Distance from House/ Building – 5 Feet (Detached ADU)

Minimum Ceiling Height- 7~ 8 Feet

Maximum Size for 1 Bedroom ADU- 850 square feet.

Maximum Size for 2 Bedroom ADU- 1000 square feet

Size requirement in case of no local regulation- 50 % of existing area of house/building.


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