San Diego ADU


 Accessory Dwelling Units (ADUs) are one of the smartest investments you can make as a San Diego homeowner. ADUs is the official acronym, but they are also referred to as granny flats, in-law suites, and casitas. Regardless of the name, a new ADU can solve many problems while adding value to your property. 

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Should You Build an ADU in San Diego?

The fresh air, cool breeze and warm sun of San Diego combine to make it one of the most beautiful places to live in California. With attractions ranging from beautiful beaches and marvelous museums, more and more people are coming to live in the city of San Diego. With the influx of people, having somewhere to stay can be a challenge, leaving living space in high demand. 

Do you have elderly parents that you want to move closer to you so you can keep an eye on them? Perhaps you have nieces or nephews looking to come to one of our amazing schools, such as San Diego State University? Maybe you just want more space for your own activities? Whatever your reasons are, finding a new place can be a challenge right now. 

Rather than looking for a new place, why not upgrade the property you already have? An Accessory Dwelling Unit can be the answer to all those problems and more. Kaminskiy Design and Remodeling will build the perfect place for your friends and family to stay when they’re in town. 

The high demand for somewhere to live in San Diego is a problem for many people. As such, it can be a major opportunity for you to earn some extra income. The average cost to rent a 500 square-foot ADU in San Diego is $1,600. When you build and rent out a granny flat, you have the option to add a significant new source of rental income to your budget. You can spend that money on your mortgage, pay off loans, save up for retirement or go on a vacation. Do note, however, that you won’t be opening up an AirBNB in your backyard; San Diego County requires all rental agreements to be at least 30 days in length. 

When you hire Kaminskiy Design and Remodeling to build you a new ADU, you are investing in your home and adding a potential revenue stream.

ADU Builder in San Diego

What is an ADU or Casita?

In Spanish, casita means “little house”.  In the home remodeling and home building world, ADUs are essentially small guest houses (typically 600 – 1200 square feet) and include a separate entrance, bathroom and small kitchen or kitchenette.  Granny Flats can be detached or attached to the main house, and are typically found in the front of properties, but can also be located in the backyard.  ADUs are often referred to as Mother-in-law-Quarters, guest houses, or granny flats and can be a great way to make your home work for multiple generations.

While you’ll likely find casitas in higher value homes (a quick Zillow search reveals that homes with advertised casitas average will over 2 million dollars), anyone with the space and budget should consider adding one.  This is especially true in areas and price ranges where a guest house is expected.  Areas like Rancho Santa Fe, Del Mar, Carmel Valley, Del Sur, Poway, Fairbanks Ranch, Carmel Canyon, and La Jolla Farms all feature real estate that is in high demand.

Best ADU Design San Diegn

Which ADU is Right for Me? 

There are three main types of Accessory Dwelling Units to consider: detached, attached, and repurposed existing. 


Detached ADU

  • The typical ADU is built in this style, usually in the backyard. 
  • A separate, standalone building, detached ADUs cannot be physically connected to the main residence in any way.  
  • The maximum ADU size is not linked to the size of the main dwelling, allowing for more freedom in design. 
  • Detached ADUs offer the most privacy for everyone on the property.
  • Existing buildings such as detached garages can be easily converted into detached ADUs.

Attached ADU

  • Attached ADUs are similar to building an addition to your home, as they are connected to the main residence. 
  • However, attached ADUs must be internally isolated from the main residence, with their own entrance, bathroom and kitchen. 
  • The max size of attached ADUs is connected to the size of the primary dwelling. Attached ADUs cannot exceed 50-percent of the total floor area of the primary dwelling.
  • Attached ADUs provide a moderate amount of privacy while still allowing easy access to and from both dwellings, which makes them a great idea for housing elderly parents or if you want to use the ADU as a gym or office. 

Convert Existing Structures to ADU

  • Repurposed Existing ADUs convert a room or space within the primary residence into an independent living space. 
  • Converting your garage, attic, or basement are all options for Repurposed Existing ADUs. 
  • You cannot change the original floor plan of the space when converting into an ADU. 
  • Repurposed Existing ADUs provide the least amount of privacy but are the most convenient to access and are usually the cheapest option for construction. 

No matter which option you choose, a few requirements must be met. 

  • All ADUs must be at least 150 square-feet. 
  • All ADUs must be no larger than 1200 square-feet. 
  • All ADUs must have a bedroom, bathroom and kitchen area. 
ADU Living in San Diego

How Much Does an ADU Cost? 

Compared to buying or building a new home, Accessory Dwelling Units cost far less to create. A small 450 square-foot ADU generally starts around $300,000 to design and build. Large 1,200 square-foot ADUs begin at approximately $475,000. With the median home price in San Diego at over $637,000, opting for an ADU is a far more affordable option.

A portion of those costs is made up of fees. Various licenses, taxes, utility fees, building codes, and city-required property upgrades must be taken into account. For example, San Diego Plan Review fees are $1,490 plus an additional $.315 per square-foot. San Diego Permit fees are $1,222 plus $.411 per square-foot. 

Permits in particular can become costly if not handled correctly. All permits have an expiration date; you must apply for a new permit if you haven’t completed construction in time. Inspections are also required every 180 days until completion. Failing an inspection requires you to start the permit process all over again, a costly mistake. Expedited permits and after-hours inspections also add additional costs. 

ADU construction costs can rise dramatically with the wrong team handling your project. While some homeowners think hiring an architect is a good idea, the price for doing so is high. Having a separate architect, designer and construction team is virtually guaranteed to cost more than an all-in-one design-build firm such as Kaminskiy Design and Remodeling. Separate teams also mean more opportunity for mistakes and miscommunication that can lead to delays and additional costs. 


Can a Casita (or any detached structure) be Included as Part of My Home’s Square Footage?

For the most part, casitas cannot be included in the overall square footage of your home.  According to the American National Standard for Single-Family Residential Buildings, any finished areas not connected to the main residence by a finished hallway or stairway must be listed separately.  If you have to leave the house to enter the structure, it cannot be included. However, if your casita is attached to the main house and you can enter it from inside, then you may include it.  This may help you decide on the layout and location for your casita or guest house.


Can I Build My Own ADU?

The smaller, simpler design of ADUs may lead some homeowners to try to take on the project themselves, going the DIY route. However, it is far more complicated than it sounds. San Diego County requires an Owner-Builder Declaration to get a building permit; this document puts you in charge of enormous liability. It also clears your homeowner’s insurance of covering injuries such as falling off a ladder, potentially leaving you with massive medical bills. 

Going the DIY route puts others at risk, too. The law considers anyone who helps you on any project that costs more than $500 to be your employee. You will be required to pay for disability insurance, unemployment, have taxes withheld, and register for an EIN on the state and federal level. Also, if you sell your property, future homeowners can hold you liable for injuries and damages that occur due to your construction.

This is why having a quality construction company is so important when you are looking to add an ADU to your property. At Kaminskiy Design and Remodeling, we specialize in delivering ADUs quickly and efficiently, so you don’t have to spend extra money on renewing permits or additional inspections. We build all our buildings with high-quality materials and skill while ensuring we keep costs in check and the project within budget.

Because ADUs are often standalone structures, they require new foundations, new walls, plumbing, electric, heating and cooling and a separate roof.  As such, it’s extremely important to hire a company with significant experience building stand-alone structures like casitas.  Kaminskiy Design & Remodeling is one of San Diego’s leading full service remodeling companies.

Remember, every project is different, and you should not accept cookie cutter options for any home addition.  Call the experts at Kaminskiy Design & Remodeling today.