Special zoning regulations apply to ADU construction in Santa Monica. ADUs are allowed in residential areas, but there are some specific restrictions. It is mandatory to follow these rules.
The size of the ADU depends on the size of the main house and the area of the plot. The following table shows the maximum permissible area:
| Lot Size | Single-Family (Maximum Floor Area Allowed) | Duplex and Multi-Family (Maximum Floor Area Allowed) |
| 6,500 | 1,400 sq ft | 1,100 sq ft |
| 8,000 | 1,700 sq ft | 1,200 sq ft |
| 12,000 | 2,200 sq ft | 1,400 sq ft |
| 16,000 | 2,900 sq ft | 1,800 sq ft |
| 22,000 | 3,200 sq ft | 2,200 sq ft |
The maximum height limit of the ADU at Santa Monica has been carefully set. The height of the main building should not exceed fifteen feet. The design of ADU is made keeping in mind the privacy of neighboring houses.
Only forty percent of the total area of the plot can be used for building coverage. Our team will help you follow this rule. This rule is helpful in maintaining greenery.
The location of the ADU should be behind or next to the main house. We will select the most suitable location by surveying your plot. This decision is based on several factors.
Single-Family Homes:
Duplexes and Multi-family:
The exterior design of the ADU should match the main house. The color, material and architectural style are carefully selected. This maintains the overall beauty of the property.
A parking lot is required for each ADU. This rule can be relaxed in certain circumstances. We will give full information about the parking rules.
It is mandatory to follow the minimum distance from the border. A distance of 20 feet has to be kept in front and 15 feet on the back. This rule ensures the privacy of neighbors.
Minimum plot areas have been set for different zones:
| Zone | Minimum Lot Area |
| R-25 | 6,000 sq. ft. |
| R-15 | 8,500 sq. ft. |
| R-9 | 11,000 sq. ft. |
| R-6 | 16,000 sq. ft. |
| R-3 | 22,000 sq. ft. |
It is very important to arrange proper utility connections for ADUs. Our team will help you plan electricity, water and sewer connections. The existing connection to the main house can be expanded or new connections can be established. This decision will be taken in consultation with local utility companies.
It is recommended to install independent meters for ADUs. This makes it easier for tenants to manage electricity and water bills. Our team will assist you in obtaining all the necessary permits. Appropriate materials and technologies will be used for utility connections.
It is mandatory to install smoke detectors and carbon monoxide alarms for fire safety. Proper emergency exit arrangements will be made. We will follow the safety rules completely.
Special permission is required to rent short-term ADUs. The rules must be followed for domestic business. We will explain all legal requirements.
All construction work will be carried out in accordance with California building codes. Safety and quality standards will be strictly adhered to. Regular inspection will be done.
Different types of permits and their costs:
| Permit Type | Cost |
| Building Permit | $2,500 – $5,500 |
| Electrical Permit | $350 – $600 |
| Plumbing Permit | $300 – $900 |
| Mechanical Permit | $250 – $600 |
| Demolition Permit | $150 – $300 |
| Landscaping Permit | $100 – $200 |
It is necessary to comply with the existing property regulations. The minimum area of the plot and the extent of building coverage will be taken care of. Our team will check all the requirements.
Additional parking space will have to be arranged for ADU. The size and location of the parking lot will be decided as per rules. Discounts may be available in certain circumstances.
A minimum distance of twenty feet must be maintained from the side of the road. This rule helps to keep Street View beautiful. We will ensure accurate measurement.
Five feet in the side yard and fifteen feet in the rear yard is mandatory. This rule ensures the privacy of neighbors. Precise parameters will be followed.
It is necessary to leave enough space for open space and garden. Greenery and natural environment will be maintained. Landscaping will be planned.
Identification of eligible properties is important for ADU construction in Santa Monica. Owners of single-family homes or duplexes located in a residential area can create an ADU. The size of the plot and the existing building coverage should be in line with the rules. Adherence to local zoning laws is essential.
Our team will verify the eligibility by evaluating your property. If your property meets all the criteria, we will guide you through the further process. We will also assist in the preparation of the necessary documents. All legal requirements will be met before ADU construction.
Multifamily properties
Junior ADUs are built inside the main house. Their maximum area is five hundred square feet. The kitchen can be shared.
The city of Santa Monica has already approved some ADU designs. Using these designs speeds up the permit process. Our team will help you choose the appropriate option.
These pre-approved designs are available in a variety of sizes and styles. We have designs ranging from one to six hundred square feet. You can choose according to your needs.
Start your ADU journey with ADU Builders CA today. Our expert team looks forward to making your dreams come true. Contact us for a free consultation.
Fire sprinklers are only required if the primary dwelling also has them.
ADUs typically require a minimum setback of 4 feet from property lines.
Separate utility connections are optional but not mandatory for most ADUs.
The checklist includes design review, site plans, structural plans, permits, and financing.
You need site plans, floor plans, construction details, and a permit application.
Inspections typically include foundation, framing, plumbing, electrical, and final review.
Work with licensed professionals to design and construct your ADU to code.
You may need to revise and resubmit plans to the Santa Monica planning office.
Submit complete and accurate documents and work with professionals to avoid delays.
ADUs under 750 sq. ft. are exempt from impact fees.
Yes, it includes checking structure, utilities, and obtaining conversion permits.
Yes, ADUs must meet height, size, and setback requirements, and their design should complement the primary dwelling.
Yes, but you need to ensure the ADU fits within allowable lot coverage and setback rules.
ADUs must comply with California Building Codes, including foundation, framing, insulation, plumbing, and electrical requirements.
Yes, ADUs must comply with California Energy Code (Title 24) and include energy-efficient windows, insulation, and appliances.
You must submit a revised plan to the Santa Monica Building Department and may incur additional fees or inspections.
Yes, ADUs near high-noise areas (e.g., busy roads) must include soundproofing measures such as double-glazed windows.
Yes, you can appeal to the city’s Planning Commission or seek adjustments to meet requirements.
Lot coverage varies by zoning but generally allows for up to 50% of the lot to be developed, including the primary dwelling and ADU.
