Conversion or New Construction: What Type of ADU is Right for Me?
Accessory Dwelling Units, or ADUs, are a hot topic in Southern California. It’s no wonder why. The shortage of affordable housing and the growth in short-term vacation rentals have created a surge in demand. Fortunately, California streamlined the ADU permit process in 2017. This is good news for San Diego homeowners and renters alike.
Whether you want monthly or short-term vacation rentals, there’s never been a better time to build an ADU in California.
But what type of ADU is right for you?
What Type of ADU Should I Build?
If you’re preparing to build an ADU, one of your first decisions is which type to build and what size it should be. The two primary types are conversion ADUs and new construction ADUs.
Conversion ADUs
A conversion ADU typically begins with a garage, sunroom, or carport. They are cost-effective and have a faster turnaround time. But, they limit your design choices, and compliance can be tricky.
Examples of conversion ADUs include:
- Carport conversion
- Garage conversion
- Pool House conversion
Junior ADU (JADU) conversion examples include:
- Attic conversion
- Sunroom conversion
New Construction ADUs
A new construction ADU requires a higher initial investment and longer completion time but offers total design freedom and modern energy-efficient features. Whether you add a detached structure or an addition to your home, your new ADU can significantly increase property value.
New Construction ADUs Ideas include:
- Detached/standalone construction
- Garden suite or backyard cottage.
- Mother-in-law or ‘granny flat’
- A new garage with an ADU above it
- A second-story ADU addition
What Should I Know Before Building an ADU in California?
To conform with ADU regulations, an ADU is designed as a house. It is designed with fire and safety codes, as well as comfort and convenience, in mind. It should have entry and exit doors, a living room, a bathroom (possibly more than one), and a kitchen. This way, the residents in the ADU do not have to come into the main house (or vice versa) to use the bathroom or kitchen.
Structures like these are desirable for vacation rentals, income properties, home offices, hobby and storage spaces, and home gyms, as well as private residences for family, friends, or others. If you have the space and permits to build a new construction ADU, it can be a fantastic way to increase the value of your home.
The size of an ADU varies. On average, ADUs today measure 600-800 s.f. The smallest is generally 250 s.f. and the largest allowed is 1,200 s.f., depending on the municipality.
Building an ADU in San Diego
Here in San Diego, detached ADUs can be built up to 1,200 square feet if they are less than 16 feet high and respect 4-foot rear and side yard setbacks. Note: It’s not always a 4-foot setback. This depends on municipality, check with your contractor for your municipality’s regulations. Considering the average apartment is 800 square feet, you’d have as much room in an ADU as in a typical apartment.
In San Diego, ADUs can be built on property that is zoned for either single-family, multi-family, or multi-generational housing (depending on the local regulations). It’s best to check with the City of San Diego before building on the land. Additionally, a lot must be free of code violations to obtain a permit.
Why should I build an ADU?
- You are an investor.
- You would like additional passive income through long-term rentals..
- You would like to increase the short and long-term value of your property.
- You have more square footage than you need or a large garage.
- You want multi-generational housing to accommodate family.
- You’re an ‘empty nester,’ and your children have moved out.
- You want to get in on the booming short-term rental market.
Is a Junior ADU (JADU) Your Best Option?
Building a Junior ADU (JADU) on your property is a good choice if you have a larger home or significant unused square footage. It’s also a good choice for people who don’t want to sacrifice their yard space. A JADU will also be ready to live in faster than new construction and entail less disruption.
When is a JADU the best choice?
- When you don’t want to lose backyard space.
- If your goal is to keep this new living space small.
- When you want a quicker turnaround time.
- If you have a larger home or children have moved out.
Conversion ADU Examples
Carport and Garage ADU Conversions
One of the most popular options is the carport or garage conversion. A garage or carport ADU is quicker to permit and build than new construction and can often be completed within 6-8 months. Costs, including architecture, permitting, site prep, and construction, vary—our ADU Investment Cost Calculator is an excellent way to get a ballpark estimate.
Patio or Sunroom Conversions
A large covered patio or spacious sunroom can also be a solid starting point for your California ADU, especially if it has a foundation. Like garage, basement, or attic conversions, they also don’t require you to change the footprint of your home or alter your property much. They generally take about the same time to complete as garage conversions.
Shed or Pool House ADU Conversion
If you have a sizable pool house or a large shed with a foundation, they may make a suitable starting point for your conversion, as long as you have at least 250-300 square feet to work with, or you can build out to that size. A separate structure from the main house appeals to most renters and can command higher rent.
Should You Choose a New Construction ADU?
A new construction ADU gives you the freedom to design precisely what you envision. While the planning and construction take a little longer, most San Diego homeowners feel it is well worth it. If you prefer not to compromise on your ADU and you have the space available, a new construction ADU will add more value to your home than a conversion can in most cases.
When is a new construction ADU the best choice?
- When you have the land area necessary.
- If your goal is a roomier living space.
- When you don’t want to compromise your vision.
- If you are seeking higher rental rates and higher property values.
Example of New Construction ADUs
Detached ADU Matched to the Home
One of the most requested options is to build a separate and detached ADU on the property, designed to match the architectural design of the main home. These add value to the home because they give the next owner options. Detached ADUs also appeal to renters.
New Garage with Second Floor ADU
If the home doesn’t have a garage, you could use another—why not build a new garage with an ADU on the second story? By building upwards, you make efficient use of your land. An outside staircase with a separate entrance keeps your garage secure and protects your renter’s privacy.
Garden Suite or Backyard Cottage
Generally built a little further from the main home, the backyard cottage or garden suite is appropriate for larger lots. They exude tons of charm and offer a bit more privacy and atmosphere. Short-term and long-term renters alike flock to them. These also make outstanding granny flats.
Specialty Design Build: San Diego’s ADU Building Experts
Building an ADU is a clever way to increase your property value and generate additional passive income. There’s never been a better time to build an ADU —- and there is no better ADU builder in California than Specialty Design Build. Be sure to download our FREE Ultimate ADU e-book to round out your knowledge on the topic!
Our streamlined design-build process makes planning easy. The services of San Diego’s most talented home and interior designers are all part of the package. Each ADU we design considers our client’s specific needs to ensure that every inch is utilized to its best potential for decades to come.
We invite you to try our ADU Investment Cost Calculator to estimate the costs of building an ADU and see the immediate and long-term ROI and home value benefits.
Contact us today to begin planning your perfect ADU project!
San Diego (858) 759-7400
North County (760) 738-6270
