What you can build

Poway ADU Regulations & Zoning


Size and Separation

Maximum size 1,500 square feet

Side/rear setbacks 4 feet

Two story Yes

Building separation 10 feet

Additional Requirements

Soils Report Yes

Building Verification Survey No

Coastal permit (in some areas) No

Stormwater Mitigation No

Number of ADUs Allowed

How many ADUs can you build in Poway?

On Poway single-family residential lots, you may build one ADU (either attached or detached) and one Junior ADU.

Note that JADUs have an owner occupancy requirement and must located within a proposed or existing main single-family residence and may include not more than 150 square feet beyond the same physical dimensions of the existing accessory structure.

How many ADUs does Poway allow for multifamily properties?

Poway allows up to 2 detached ADUs for multifamily lots with an existing multi-family building. (Meaning: In order to build 2 ADUs, the property must already have at least a duplex on it, not just a single family dwelling)

Non‐livable space within existing multi‐family structures may be converted into an ADU. Examples of areas that can be converted include storage rooms and garage spaces. The maximum number of ADU allowed in a multi‐family structure is equal to 25% of the number of existing multi‐family units in the structure. Fractional units are rounded down. A minimum of one conversion ADU is allowed.

ADU Size & Building Constraints

What size detached ADU can you build in Poway?

Poway allows for a detached ADU of up to 1200-1500 sqft. If you are building larger than 1200 sqft, the unit may only be up to 50% of the floor area of the Single Family Residence (SFR). ADUs up to 800 square feet are exempt from lot coverage requirements. (Meaning: You can build an ADU of this size even if you’re maxed out on lot coverages).

What is the height requirement for an ADU in Poway? Can you build a two story ADU in Poway?

The height of a detached ADU can be up to 16′ and one story, unless the ADU meets the required setbacks for the SFR, in which case the height can be at or below the height of the existing residence.

Also, per recent state law change, detached ADUs within half a mile of major transit stops or high-quality transit corridors can use 4′ side & rear setbacks, up to 18 feet tall. An additional 2 feet can be added if the ADU’s roof pitch matches the primary dwelling. This 18’+2′ limit would allow for a two story unit.

Read more about two story ADUs and height limits.

How big can an attached ADU be in Poway?

The square footage of any attached ADU may not to exceed 50% of the primary dwelling square footage, or 1,500 sqft, whichever is less. However, a minimum
1,000 sf for a 1-BR+ ADU or 850 sf for a “studio” ADU is permitted.

“Attached” to the main residence requires a roof attachment equal to the width of the structure to be attached and shall not be greater than 10 feet from the main residence, excluding eaves. The roof of the structure to be attached shall match the eave widths and roofing materials, color and style of the main residence.

What are the requirements of the exterior of the ADU?

Poway requires architectural consistency between the ADU and the primary structure. The exterior roofing, trim, walls, windows and the color palette of the ADU shall incorporate the same features as the primary dwelling unit. Note that this can add some expense beyond our standard build prices, which includes stucco, asphalt shingles and white vinyl windows.


What is the setback requirement for an ADU in Poway?

ADUs must have 4′ minimum setbacks from rear and side-yard property lines, with front yard setback per zoning standards. An ADU taking advantage of the 4′ setbacks cannot exceed a height of 16 feet. An ADU exceeding 16′ must comply with the setbacks of the underlying zoning.

What is the minimum distance the ADU must be from existing structures?

The minimum required distance between structures is 10′.

Additional Requirements

Does Poway require in-person submission of plans for an ADU?

Yes, Poway requires in-person submission of plans and does not accept digital applications at this time.

Does Poway require a soils report for an ADU?

Yes, as of a July 2022 email from the Planning department, Poway mandates soils reports for all new structures, including ADUs.

Does Poway require coastal development permits?

No areas are subject to Coastal requirements.

Does Poway require erosion control measures?

Yes, Poway requires that any disturbed soil must be covered. This includes the 5′ graded area surrounding the ADU, the pathway to the ADU, and any additional areas impacted by work.


How many ADUs does Poway allow for multifamily properties?

Up to two detached accessory dwelling units shall be permitted on a lot with an existing multifamily dwelling.

Can you stack detached ADUs on top of each other?

Yes, if the ADUs meet the required setbacks for the SFR, in which case the height may be allowed to match the existing residence. Otherwise height must not exceed 16′.

Can you attach two ADUs to each other in Poway?

It is currently undetermined if two detached ADUs can be attached to each other; this will be subject to city interpretation.

Can you convert existing space to an ADU?

Yes, existing non-livable space may be converted to ADUs (e.g. storage areas and garages). The minimum number of ADU conversions allowed is one, up to a maximum equal to 25% of the number of existing multifamily units. This is in addition to the allowed number of detached ADUs.


What is the parking requirement for an ADU in Poway?

A parking space is not required for an ADU in any of the following instances:

  • Within a one-half mile walking distance from public transit, which includes bus stops.
  • Within an established historic district.
  • Converted from the existing space of a primary residence or accessory structure, or are attached to an existing or proposed primary residence.
Where can a parking space be located?

If a parking space is required, it may be located within the setbacks and in an existing driveway as tandem parking. Parking spaces don’t need to be replaced when a garage, carport, or covered parking structure is demolished in conjunction with the construction of an ADU or converted to an ADU.