Get answers on your ADU project

Frequently Asked Questions

Below are the common questions we hear about ADU regulations, cost, financing, timelines, working with Snap ADU, pre-approved plans, rentals & investments and more. Contact us to talk about specifics of your ADU project.

What & Where Can I Build My ADU?

How large an ADU can I build?

Generally, you will be able to build at least a 1000 sqft ADU, and up to 1200 sqft in some cases. Read our guide to ADU size maximums and see city-by-city ADU regulations here.

What is the minimum lot size for an ADU?

There are no minimum lot sizes for accessory dwelling units per California state code. Even if there is a coverage ratio maxed out on your property, you are still allowed to build at least an 800 sqft ADU.

Where on my lot can I build an ADU?

Per state law, setbacks for new ADUs have been reduced to 4′ for side and rear yards. The City of San Diego went even further and has established 0′ setbacks on the side and rear yards for ADUs. Also, no setbacks are required if an existing and permitted accessory structure is being converted. You can even remove an existing structure (like an old garage) and replace it with a new ADU that matches the old footprint, even if the old structure had pre-existing reduced setbacks.

Any new addition must comply with setbacks, with exception of up to a 30′ encroachment (e.g. above a garage that is at the lot line). Some municipalities have minimum building setbacks, meaning the ADU must be a minimum distance from the primary residence; state guidance defers to local regulations in this case, and typical is 5 to 10 feet (though some cities do not list a minimum; fire code is still a consideration, which is why we usually hold at least 6′ from existing structures). Read more about ADU setbacks and fire ratings.

Can I build an ADU in my front yard?

Yes, you can generally build an ADU in your front yard if it complies with underlying setbacks for your lot. A local agency may still apply front yard setbacks for ADUs.

However, front yard setbacks cannot preclude an ADU of at least 800 square feet and must not unduly constrain the creation of all types of ADUs (Gov. Code, § 65852.2, subd. (c) and (e)). To successfully argue for an ADU in the front yard setback, it would have to be the case that nowhere else on the property can accommodate an ADU. We have seen this happen when there is only one yard to the property (e.g. a side/front yard). But if you just want to build in the front to preserve your large back yard? It’s unfortunately not possible unless the ADU conforms to the front setback.

What’s the most advantageous size ADU to build?

If your ADU is under 500 sqft, it will not require civil engineering review (stormwater, catch basins etc). If your ADU is under 750 sqft, you will not incur impact fees (except for the school fees which are still due even after the new regulations). Our standard 1BR and 2BR designs are under 500 sqft and 750 sqft to help you avoid those additional costs (typically $3-5K). Check out our article on what size ADU to build, and also what to look for in an ideal lot.

How many ADUs can I build?

New state laws permit two ADUs on a single family zoned property… one full Accessory Dwelling Unit (ADU) and one Junior Accessory Dwelling Unit (JADU). On multifamily properties, you can build up to two detached ADUs. Read about whether you may be able to “stack” them on top of each other in your jurisdiction. In the City of San Diego, you may be able to construct even more ADUs under the Affordable ADU Bonus Program if you will rent the units to low or moderate income families.

What is a Junior ADU?

A Junior Accessory Dwelling Unit (JADU) is defined as a complete independent living facility not to exceed 500 sqft in size and contained entirely within an existing or proposed single family home (think garage or spare bedroom). A JADU must have a separate exterior access, as well as a full bathroom and efficiency kitchen. The kitchen must have a cooking facility with appliances, a food preparation counter, and storage cabinets. Sometimes we are asked about opting for a “wet bar” instead, which could then prevent a living space from being deemed a JADU. Rules will vary by jurisdiction, but the County of San Diego specifies that a wet bar may not have more than 10′ of cabinets in total length, a single-basin sink of not more than 18″ wide, a fridge of max capacity <=5 cubic feet, no gas or 220 volt AC power outlets in vicinity, and so long as the room “is not designed so that it could easily result in an unpermitted ADU.” As far as adding a pool house and skirting the rules to get a second detached ADU-esque structure on the property… there is specific guidance from the County of San Diego about what constitutes habitable vs non-habitable space that would prevent a homeowner from creating a detached structure (other than an ADU) with features like a bath or stubbed out plumbing/sewer connections.

Can you attach a JADU to an ADU? Can they be detached from the primary residence?

No, a junior accessory dwelling unit (JADU) must be created from existing space within the primary dwelling unit. A JADU cannot be built as part of a detached ADU.

Note that a JADU is only possible on a single family lot, as JADUs are not allowed on multifamily lots (which already typically allow two ADUs – check out city ADU regulations pages for rules by municipality).

Also note that, until December of 2023, the City of San Diego did permit a JADU to be attached to an ADU. They closed that option as part of the Housing Action Plan 2.0.

Can I convert or attach to an existing structure (old shed / garage / outbuilding)?

Yes. Though from a feasibility standpoint, starting from scratch will often be easier and cheaper. Trying to tie into an existing outbuilding can be problematic, especially when it comes to footings and having proper compaction. Grading work done decades prior is not up to par with current standards. When we dig the footings for the new structure up against the existing, often we cannot get compaction and are exposed to settlement issues.

If I have an empty lot, can I build an ADU first and then build a house later?

An ADU is a designation that can’t exist by itself – there must also be a primary residence – so the initial home will be considered the primary residence. Then once you build the second larger home, you would then “convert” the status of the original building to an ADU. This means you would need to ensure the first structure you build (what you would later call the ADU) will conform to both the requirements for a primary dwelling AND the requirements for an ADU. Read more about if you can build an ADU before the main home.

Can I build an ADU in a historic district or if the primary residence is subject to historic preservation, e.g. the Mills Act?

Yes, ADUs are allowed within a historic district and on lots where the primary residence is subject to historic preservation, for example via the Mills Act. California State ADU Law allows for a local agency to impose standards that prevent adverse impacts on any property that is listed in the California Register of Historical Resources, but these standards do not apply to ADUs proposed pursuant to Government Code section 65852.2, subdivision (e). A jurisdiction may impose objective and ministerial standards that are sufficiently objective to be reviewed ministerially and do not unduly burden the creation of ADUs (Gov. Code, § 65852.2, subds. (a)(1)(B)(i) and (a)(5)).

Accessory Dwelling Unit Costs

How much will it cost to build a standalone ADU?

We have an entire page devoted to explaining ADU build costs. Read more about all of the costs that will go into designing, permitting & building your ADU… we want you to know about all the potential costs before you get started.

How much will it cost to convert my garage into an ADU?

The cost would be around $120K for a standard garage conversion project of about 400 sqft. We no longer handle conversion work as we are focused on becoming extremely effective at building standalone ADUs.

What are the fees?

Prior to Jan. 1, 2020 when new ADU and affordable housing laws went into effect, cities could charge development and impact fees that could total $15,000-30,000. However, with the passage of recent state laws, impact fees on ADUs less than 750 square feet have been completely eliminated. Fees on ADUs 750 square feet or more must now be proportional to the size of the ADU relative to the primary dwelling unit. ADUs will still trigger sewer connection fees and capacity fees, but those fees must also be proportionate to the size of the ADU. In total, permit fees have been reduced to $5,000-12,000 on average (or about $10/sqft of the ADU size). Read more about the different types of fees when building an ADU.

How does Snap ADU pricing work?

We will give you a high-level estimate in our first phone call based on your description of the project and your site. If we determine your project is a fit, we issue a proposal that includes your expected price for each phase of the project, including design, sitework, and construction. If you do move forward with SnapADU, we finalize your ADU build price during our first step of Feasibility & Design so that you know the full cost of you ADU upfront; we absorb the risk of labor & material price fluctuations. Read our blog on ADU pricing to understand how we work hard to refine your budget so we minimize surprises over the entire process.

Can you provide a price off of plans?

Yes, we are happy to look at your ADU plans to see if we can offer a proposal to build, though most of our work is design/build.

Can I provide my own finish materials to save money?

You can, but we typically don’t find clients can save a lot of money by doing so. We have trade agreements in place with suppliers, which help us provide our clients very competitive pricing on finish items – often at the same or better pricing than could be found elsewhere. Additionally, we have already screened materials to ensure the specifications will work together. However, if you want to provide your own finish materials, that is something we accommodate during the Selection process. You can either provide the items yourself, or work with our vendors to source custom materials.

ADU Financing

What are financing options?

We work with several providers who can help you navigate financing options to narrow your choices and determine which path is best for you. Check out an overview of ADU Financing Options to learn more about loan products that fund an ADU.

Do you work with construction financing?

Yes, we work with you and your lender to ensure you have the required plans, scope of work, and budget required to submit for loan documentation. If you don’t already have a lender, we are happy to put you in touch with some contacts and help you through that process.

Working with SnapADU

What is your typical process for working with a new customer?

Once you fill out a brief Project Assessment, we get into the details with you right away to make sure your project is feasible and that your vision is aligned with your budget. Read about our overall process from the time we first interact to the time we hand you the keys. Also read about our user-friendly interface, BuilderTrend, where we manage your entire project.

Do you provide free consultations?

Yes, we are happy to answer feasibility questions, provide ballpark estimates, and get into details quickly about your property specifics so you can decide if an ADU project is right for you and, more specifically, if you’d like to work with us. Contact us to get started on the free discovery process.

Do you design custom plans?

Yes! We offer custom, standard, and semi-custom plans. Read more about custom ADUs and custom ADU floor plans, and check out all our standard floor plans as a jumping off point.

Do I need to have plans before I start with SnapADU?

No, in fact we offer the most competitive pricing if you pick from our standard plans, or work with us to customize an existing plan to suit your needs. You can also provide us with a sketch of your ideas or your “wish list” and we will design something custom for you.

Do you offer just plans & permitting, or only design-build?

Our primary focus is on design-build projects, providing an integrated, end-to-end experience for our clients. While we don’t exclusively offer design & permitting services, if you’re open to considering the complete design-build approach, we’re here to guide you every step of the way. And why choose a design-build general contractor like SnapADU over separate teams of professionals? Here’s a snapshot of the benefits:

  • Accountability: Our singular focus on design-build ensures seamless project execution. We are entirely accountable, aligning with the commitments made during the feasibility study.
  • Transparent Budgeting: Our approach centers around clear budgeting. We provide an unambiguous view of the complete costs right from the outset.
  • Guaranteed Price: With SnapADU, you get a fixed build price. This ensures budget predictability with no surprises.
  • Efficiency: Our in-house permitting team ensures that the project moves swiftly and efficiently, eliminating potential delays that can arise from multiple handoffs.
  • Quality: A collaborative, unified team means that the end result will be of the highest standard.
  • Cost Savings: A significant number of projects encounter cities that may misinterpret ADU regulations, leading to unnecessary costs. Our seasoned team is well-equipped to advocate for you, ensuring you aren’t paying more than you need to.

What work does SnapADU do in-house?

We are a licensed general contractor and provide a design/build service, meaning you work with us for your entire project and we are fully accountable. We will be on point for getting the job done during design, permitting and in the field. We subcontract out trades like concrete, framing, drywall, plumbing, electrical, HVAC, tile & stucco. We also partner with select septic companies, geotechnical engineers, civil engineers, and structural engineers for the site planning phase of the work. All the rest of the work is done in-house by our team, including design & permitting.

What areas do you serve?

We build ADUs throughout Greater San Diego, including Oceanside, Carlsbad, Encinitas, Vista, San Marcos, Escondido, Solana Beach, Del Mar, Poway, La Mesa, El Cajon, Chula Vista and surrounding areas. See our service area map.

What construction type does SnapADU use?

Our ADUs are “stick built” construction and are not prefab ADUs, mobile or manufactured homes. All of our ADUs are built on site using conventional framing methods, though we utilize some offsite processes that improve our quality control and timeline. We regularly evaluate new technology to make sure we are offering a competitive product.

Do you handle remodels? What about landscaping or other backyard projects?

In a world where versatility is often praised, there’s still immense value in specialization. We have made a deliberate decision to focus solely on detached ADU (Accessory Dwelling Unit) design and build for several key reasons:

  1. Expertise Through Specialization: By dedicating ourselves exclusively to detached ADUs, we’ve refined our skill set to become true experts in this niche area. This enables us to maintain the highest quality standards and keep up with the latest best practices, ensuring our clients receive nothing but the best. From initial planning and design to the final stages of construction, our in-house team collaborates seamlessly, ensuring a cohesive and efficient project flow.

  2. External Elements Can Be Managed Post-Completion: While elements like landscaping, patios, or other auxiliary structures can enhance the overall aesthetic and functionality of a property, they are not integral to the ADU construction process. These components can be executed after our work is done. We’ve found that many homeowners have preferred vendors for such tasks or may even choose to undertake some projects DIY-style. By allowing homeowners the flexibility to manage these elements separately, they often find opportunities for cost savings and personalized touches.

  3. Home Additions and Remodels Present Unique Challenges: Working on additions or remodels is fundamentally different from constructing a detached ADU. Such projects require extensive coordination with existing structures and conditions, which can be unpredictable and may lead to extended timelines and unforeseen expenses. Our commitment to transparency, predictability, and excellence means we avoid venturing into areas that could compromise these values.

While there are countless avenues in the world of construction and design, we’ve found our passion and expertise in ADUs — and we’re committed to being the best in this space.

Does SnapADU provide a warranty?

Yes, SnapADU provides comprehensive warranties as part of our construction agreement. Our commitment includes:

  • 1-year Full-Service Warranty on all workmanship and materials we manage or procure, ensuring adherence to the NAHB Residential Construction Performance Guidelines – Fifth Edition. This warranty covers defects not caused by normal wear and tear or homeowner neglect.
  • 2-year Full MEP Warranty on all mechanical, electrical, and plumbing (MEP) systems, including solar/photovoltaic systems
  • 10-year Structural Warranty against structural defects, contingent on our adherence to approved plans and specifications.

A soils report is an optional step in most jurisdictions. Declining a soils report means that no soils compaction testing will be performed by a Geotechnical Engineer, and the ADU will be built to the most stringent UBC design standards & thresholds. In such cases when a soils report is declined, SnapADU will not be responsible for issues stemming from insufficient soil conditions.

ADU Process & Timeline

How long does the whole process take?

The entire process from signing a proposal to moving into a completed ADU takes 8-12 months.

How long is the approval process with the city?

Cities must act on an application for an ADU within 60 days of receiving the application in cases where there is an existing single family dwelling on the lot. We are also seeing some cities enact “queues” for review, especially when they are facing staffing crunches like many industries are right now. We keep our clients updated on what to expect in their city.

Are ADU permits “over the counter”?

In short, the answer is no. State laws passed in 2020 made obtaining a new ADU easier with “ministerial approval,” which refers to a streamlined permit process for development approval involving little or no personal judgment by the public official. The official’s “discretion” on whether to approve the permit has been eliminated, as well as factors such as design features and size. Thus, only the municipal code or state laws will be considered in the approval process. A plan must still be formally submitted to the city and reviewed to confirm the plans adhere to the state and local ADU laws, building code, etc.

What factors will most affect the timeline?

Permitting with the city still takes a big chunk of time. The build-out is another large chunk of time. It’s a process that includes hundreds of decisions and to-dos, so even losing half a day on tasks can add up significantly. This is why we manage all our projects using BuilderTrend to communicate seamlessly with the client, vendors, subcontractors, and within our team.

Do you measure my site remotely?

Yes, when we discuss your project, one of the first steps is to assess the existing conditions of the property. We work with a provider that licenses a large data set that includes lot dimensions, land use, lot square footage, building square footage, zoning and more. This is cross-referenced with plot plan information and several different sources of satellite imagery to ensure accurate lot dimensions. When matched up with ADU regulations for your lot, this enables sufficient accuracy for us to position a chosen ADU floor plan on your site plan for the purposes of a Proposal.

When you decide to move forward, the first part of our project with you will be to verify all of our assumptions by going on-site to measure existing utilities, assess required upgrades, and ensure that the site assumptions we made were accurate. We will also refine your site plan, floor plan, elevations, and electrical plan based on all these inputs. You will review and sign off at this phase to lock in your pricing and authorize us to move on to your full set of construction docments for the city.

Do I need a survey for my ADU?

It’s very likely. Unfortunately there is not a one size fits all answer, since the need for a survey is very dependent upon the site conditions, local codes, and the building inspector. More cities are requiring a survey for an ADU, though the final decision is up to the inspector. Read more about the need for an ADU survey.

Pre-Approved Plans From San Diego County + Encinitas

What are “pre-approved” or “permit-ready” ADU plans?

The County of San Diego and Encinitas have made several ADU plans available to the public. Encinitas calls theirs the Permit-Ready Accessory Dwelling Unit (PRADU) Program.

Will using pre-approved plans save money & time?

Sometimes. If you can use a plan exactly as-is, you may not need to pay for architectural plans. You will also still need a site plan along with Title 24 calculations. And lastly, since most of the costs of your ADU project are in the actual sitework and build-out (not the design phase), the few thousand you may save on plans may vanish because of higher build costs. We’ve put together a guide so you can assess whether a pre-approved plan might work best for your ADU.

ADU Properties: Rentals & Investments

Can I use an ADU for short term rental?

Any newly constructed ADUs may only be rented for periods of more than 30 days. This is a state-wide requirement designed to curb the use of ADUs for short-term rental. A city cannot issue a building permit until you have signed a covenant that agrees you will not rent the ADU for less than 30 days. You do, however, have the option of moving into the ADU and renting out your primary residence as a short-term rental (except in Oceanside, where neither the ADU nor the primary may be used as a short term rental). Read more about renting out an ADU.

Can I add ADUs to multifamily property?

Yes. Per state ADU code, if you have a structure of two or more residential dwellings that are attached to each other (e.g. a duplex) and in a residential zone, you may add two detached ADUs. You can also convert accessory space within the existing structure to an ADU. Read more about adding ADUs to multifamily properties.

Is there an owner occupancy requirement?

No! Owner occupancy requirements have been permanently banned by the State of California (AB 976), meaning you could add an ADU on a rental property. This is not the case for JADUs, which do have an owner occupancy requirement. Read more about owner occupancy requirements here.

Other FAQs

Do I need to add parking for the ADU?

ADUs do not require parking if they are within a half mile walking distance of public transit or created within an existing space in your house or an accessory structure, like a garage or carport. Additionally, no replacement parking is required for the main residence when a garage or carport is demolished or converted to create an ADU. Otherwise, parking requirements for ADUs are one parking space per unit or per bedroom (whichever is less). JADUs do not require parking.

Typically, cities have accepted showing replacement parking in the driveway. We can also convert existing landscaping to parking, so long as this parking does not exceed the lot coverage allowed per the zoning.

What about my HOA?

Neither HOAs (Home Owners Associations) nor property CC&Rs (Covenants, Conditions and Restrictions) can “reasonably prohibit” development of an ADU or JADU. However, they can make it more time consuming and expensive for you. Read more about HOAs and ADUs on our blog.

Can I sell the ADU separately from my house?

Until recently, an ADU could not be sold separately from the primary residence due to California state law. However, AB 1033 lets cities and counties decide whether to offer the option of condo conversion in their jurisdiction. This is a new development as of Fall 2023. Read more about AB 1033 and selling ADUs.

Does an ADU have a separate address?

Yes, an ADU is typically designated with a separate address for fire safety reasons (so the fire department would know where to go).

Read more about ADU address requirements.

Will the ADU have a separate utility bill from the main home?

Yes, an ADU will receive a separate electric bill from SDGE. This is because all ADUs must be metered separately for electrical service. Read more about electric panels and service upgrades for ADUs.

Water service can be metered privately by means of a metering device that is located on the ADU. Upon request, SnapADU will provide the preparation to accept a metering device which can be connected to WiFi and monitored remotely on your smartphone or computer. We recommend this product as a WiFi enabled water meter. Learn more about water, gas, and sewer connections for your ADU.

Does adding an ADU increase my property taxes?

Yes, the state will conduct a “blended assessment” to determine your taxes. This means the base value of the existing house will stay the same, and your ADU’s additional value will be added to the existing home’s value. Once this new assessed value for the ADU + property is set, the property value will then be taxed at 1-2% annually. This is generally an increase of $2-4K in taxes a year for a typical ADU. Learn more about ADU property taxes.

Can I add an ADU in a Coastal Zone?

Probably yes. Getting a permit for an ADU in the coastal zone is becoming much more likely, though the process may take time. Usually if there is a Local Coastal Program (LCP) in place by the city to handle low impact Coastal Commission projects, then it can be handled by the LCP at the city level. LCPs are catching up to state ADU legislation in favor of ADUs, though in some areas, restrictions are still more stringent (e.g. bluff top size, hillside overlay zone, wildland urban interface etc). Read much more in our blog about Granny Flats in The Coastal Zone.

What about existing “illegal” or non-permitted ADUs or Junior ADUs on my property?

When you build your new ADU, you may have to address permitting for any “illegal” or unpermitted ADUs on the property. The process is similar to bringing an illegal addition into compliance. It would require drawing a plan for the existing structure (typically $2000-3000), sending it to plan check at the city (planning, building, and fire), potentially conducting an exploratory phase where walls are opened up for inspection with the city (typically no more than $1000-2000 for opening walls and repairing them), addressing anything in the structure that is not within compliance (cost will of course depend on what’s going on with your structure), and paying for any permits (typically $1000). Any tenants in your existing ADU likely will not need to vacate during this process.

What advice would you give a customer looking to hire an ADU contractor?

Consider the visibility you will have into the project. How does the company handle project management? What tools will enable you to stay up to date on progress? How easy is it to work with the company on things like payments and material selections? Pick someone you trust & will be excited to interact with about your project on a regular basis… it should be a pleasure to discuss your project, not a chore. It’s also important to engage a contractor early on to provide cost analysis and make sure you are designing within your budget. Read more about what to look for in a contractor.

I’m a subcontractor who would like to work with SnapADU. How can I apply?

We are always looking for great new trade partners. Fill out our vendor application here to see if there is a good fit with SnapADU.

I'm a realtor interested in ADUs. Where do I start?