ADU Costs and Financing in Roseville and
Throughout Placer County
Understanding ADU costs and financing in Roseville and throughout Placer County, California, doesn't have
to be complicated. Most statewide ADU pricing and loan options apply locally, making valuable
information readily available—if you know where to look.
Discover How Much It Really Costs to Build an ADU in Roseville and Placer County
Roseville, a thriving suburb of Sacramento, is located within Placer County, California. Covering just over 40 square miles, Roseville, CA features numerous neighborhoods with convenient access to local streams and natural areas. As of the 2020 census, its population stands at approximately 120,000 residents.
Placer County itself spans roughly 1,500 square miles and has a population of just over 400,000 people. Extending approximately 65 miles eastward from Roseville, Placer County reaches the Nevada state border and includes a portion of the picturesque Lake Tahoe shoreline.
Both Roseville and the broader Placer County area offer homeowners numerous opportunities to utilize an ADU—from accommodating aging family members to generating income through Airbnb rentals. With residents over age 65 comprising approximately 15%-20% of the local population, the demand for granny flats, backyard bungalows, and other types of ADUs continues to grow.
In this guide, we provide homeowners in Roseville and throughout Placer County with an in-depth look at the costs and financing options available for ADU construction projects. We'll cover the range of financing methods commonly used by homeowners in the area, including some innovative, modern approaches. Additionally, we'll provide helpful links to relevant government agencies and share practical tips to help you avoid common pitfalls faced by first-time ADU builders.
Are You Wondering What Your ADU Will Cost?
Get a free, custom estimate from Roseville’s top-rated ADU contractor—RALH Construction.
What Is an ADU (Accessory Dwelling Unit) and What Is it For?
An ADU, an acronym for the term accessory dwelling unit, is the overarching term given to home additions and construction projects that create a new, independent living space.
ADU construction projects must add basic amenities, like electrical power, access to food preparation, a bathroom with bathing facilities, and most of the time a bedroom, though studio ADUs without separate bedrooms are also being built and recognized as ADUs.
ADUs create new living space for family members, guests, renters, or other occupants separate from the main home on a single family lot. So, a home addition that only added a bathroom and/or a bedroom would not qualify as an ADU, unless access to a kitchen was also added.
ADU classification can be important for residents of California, because California is by far the most ADU friendly state in the US. California offers ADU friendly legislation designed to make adding an ADU easier, and even subsidizes the financing in some situations.
Want to learn more about ADUs? Check out our complete ADU guide here!
Which ADU Financing Methods Are Most Popular In Roseville and throughout Placer County?
Here is a partial list of popular ADU financing methods used in Placer County, but new creative financing methods pop up all the time:
Cash
- No interest or monthly payments
- Best option for cost savings
- Fastest way to complete construction
Home Equity Loan
- Home equity loans use the owner’s equity in the property as collateral in exchange for a lump sum loan. The borrower (owner) usually pays back the principal (the amount borrowed) and interest over a set period of months or years.
- Home equity loans are popular in Placer County because home values have consistently risen over the last couple of decades. This has allowed homeowners access to free equity, which many use to finance an ADU addition.
Pros: This loan offers a fixed rate and payments include principal and interest for a fixed period of time.
Cons: No flexibility to draw more equity later on without a complete refinance of the loan. The payment does not adjust if you pay it down a substantial amount.
This is best if you are looking for a fixed interest rate and an amortized loan and have a primary mortgage already but don’t want to touch your existing rate or payment by doing a full refinance.
HELOC (Home Equity Line of Credit)
- Borrow against home equity to finance ADU construction
- Flexible loan option with lower interest rates
- Variable balance allows the borrower to control the monthly payment
Pros: You only make payments on what you have drawn out. You can take money out in a 24 hour period if needed
Cons: The minimum payments are interest only and you are dealing with an adjustable rate.
This is the best option if you have a primary mortgage already, but don’t want to touch your existing rate or payment.
Cash Out Refinance
- Refinance an existing mortgage to fund ADU construction
- Can be a first or second mortgage
- Generally not available on more than 80% of the owner’s equity
ADU Construction Loan
- Short-term loan for covering construction costs, then converts into a mortgage. Sometimes the owner finances the construction with personal funds, then applies for a mortgage after completion.
Equity Sharing Agreements
Equity sharing agreements are a modern way for homeowners in areas of rising home values to profit in advance of a sale. The investment company does not loan the money to the owner, but rather purchases an interest in the property. The money is not repaid to the investor whether the property loses, or gains, value.
In an equity sharing agreement an investment company offers to purchase a percentage of ownership in the structure. The hope is that when the property is sold in the future, the value of the investor’s percentage will have increased.
Therefore, only properties projected to increase in value will be offered an equity sharing agreement. These investment companies will lose money if the property value falls, as will the owner.
CAlHFA ADU Grant ($40,000 State Grant)
Covers pre-construction costs such as permits, design, and feasibility studies. To apply for the $40,000 state grant, the borrower must meet these requirements:
- The owner must own and live on the property where the ADU will be built.
- The household income must be at or below 80% of the area median income for the area.
- The property must be a single-family home zoned for ADUs
To access the online CalHFA application, click here.
CalHFA also offers financial assistance for low and middle-income residents in other forms as well. Click here to be redirected to the CalHFA Financial Hardship website for more information.
Fannie Mae HomeStyle and FHA 203K Loans
- Government-backed loans that bundle home purchase/renovation with ADU financing. Here’s a link to the FannieMae HomeStyle Renovation program.
Local Grants and Incentives (Check for updates in Placer County)
- Provides potential county level financing assistance for homeowners. The program is currently on hold as of 2025, but essentially promotes the CalHFA grant program. Here’s a link to the Placer County ADU Financing Page: Placer County Grant Assistance
Private and Unsecured Loans
- Private loans can come from friends, family, and business partners interested in ADU investment. These loans can be secured with collateral, or left unsecured, at the parties discretion.
What Is an ADU (Accessory Dwelling Unit) and What Is it For?
An ADU, an acronym for the term accessory dwelling unit, is the overarching term given to home additions and construction projects that create a new, independent living space.
ADU construction projects must add basic amenities, like electrical power, access to food preparation, a bathroom with bathing facilities, and most of the time a bedroom, though studio ADUs without separate bedrooms are also being built and recognized as ADUs.
ADUs create new living space for family members, guests, renters, or other occupants separate from the main home on a single family lot. So, a home addition that only added a bathroom and/or a bedroom would not qualify as an ADU, unless access to a kitchen was also added.
ADU classification can be important for residents of California, because California is by far the most ADU friendly state in the US. California offers ADU friendly legislation designed to make adding an ADU easier, and even subsidizes the financing in some situations.
Want to learn more about ADUs? Check out our complete ADU guide here!
Which ADU Financing Methods Are Most Popular In Roseville and throughout Placer County?
Here is a partial list of popular ADU financing methods used in Placer County, but new creative financing methods pop up all the time:
Cash
- No interest or monthly payments
- Best option for cost savings
- Fastest way to complete construction
Home Equity Loan
Home equity loans use the owner’s equity in the property as collateral in exchange for a lump sum loan. The borrower (owner) usually pays back the principal (the amount borrowed) and interest over a set period of months or years.
Home equity loans are popular in Placer County because home values have consistently risen over the last couple of decades. This has allowed homeowners access to free equity, which many use to finance an ADU addition.
Home equity loans are popular in Placer County because home values have consistently risen over the last couple of decades. This has allowed homeowners access to free equity, which many use to finance an ADU addition.
HELOC (Home Equity Line of Credit)
- Borrow against home equity to finance ADU construction
- Flexible loan option with lower interest rates
- Variable balance allows the borrower to control the monthly payment
Cash Out Refinance
- Refinance an existing mortgage to fund ADU construction
- Can be a first or second mortgage
- Generally not available on more than 80% of the owner’s equity
ADU Construction Loan
- Short-term loan for covering construction costs, then converts into a mortgage. Sometimes the owner finances the construction with personal funds, then applies for a mortgage after completion.
Equity Sharing Agreements
Equity sharing agreements are a modern way for homeowners in areas of rising home values to profit in advance of a sale. The investment company does not loan the money to the owner, but rather purchases an interest in the property. The money is not repaid to the investor whether the property loses, or gains, value.
In an equity sharing agreement an investment company offers to purchase a percentage of ownership in the structure. The hope is that when the property is sold in the future, the value of the investor’s percentage will have increased.
Therefore, only properties projected to increase in value will be offered an equity sharing agreement. These investment companies will lose money if the property value falls, as will the owner.
CalHFA ADU Grant ($40,000 State Grant)
Covers pre-construction costs such as permits, design, and feasibility studies. To apply for the $40,000 state grant, the borrower must meet these requirements:
- The owner must own and live on the property where the ADU will be built.
- The household income must be at or below 80% of the area median income for the area.
- The property must be a single-family home zoned for ADUs.
To access the online CalHFA application, click here.
CalHFA also offers financial assistance for low and middle income residents in other forms as well. Click here to be redirected to the CalHFA Financial Hardship application.
Fannie Mae HomeStyle and FHA 203K Loans
- Government-backed loans that bundle home purchase/renovation with ADU financing. Here's a link to the FannieMae HomeStyle Renovation program.
Local Grants and Incentives (Check for updates in Placer County)
- Provides potential county level financing assistance for homeowners. The program is currently on hold as of 2025, but essentially promotes the CalHFA grant program. Here’s a link to the Placer County ADU Financing Page: Placer County Grant Assistance
Private and Unsecured Loans
- Private loans can come from friends, family, and business partners interested in ADU investment. These loans can be secured with collateral, or left unsecured, at the parties discretion.
Expert Insights from a Local ADU Financing Specialist
“Choosing the right financing method for your ADU project depends on your unique situation.”
— Lindsay Boris, Production Manager at American Pacific Mortgage (Roseville, CA)
HELOC (Home Equity Line of Credit):
“HELOCs are great for homeowners who prefer flexibility. You only pay interest on what you draw, but keep in mind the rate is adjustable.”
HELOAN (Home Equity Loan):
“Ideal for those wanting predictable payments. You get a fixed rate and set payment schedule, but less flexibility if you need more funds later.”
Renovation Loan:
“Perfect if you have limited equity or no existing mortgage. Renovation loans use the future home value after ADU construction, often offering a lower interest rate compared to other second mortgages.”
How Much Does It Cost to Build an ADU In Placer County?
In Placer County the cost of building an ADU can vary widely depending on where the ADU is located, its size, and its available uses. In Tahoe City, for example, the average cost per square foot for new construction was a staggering $1278.00/square foot.
Cost Factors That Affect ADU Pricing
The cost of constructing an ADU is greatly affected by the type of construction, the size, the materials, and the site conditions, such as available utilities.
Generally, expect the materials to contribute about 60% to the total cost, with labor representing about 30%, and design and fees accounting for the final 10%.
Here is a partial list of factors that can significantly affect the cost of building an ADU in Placer County:
Cost Breakdown: Hard Costs vs. Soft Costs
Hard Costs
Generally, hard costs describe expenses for materials, labor, machinery, structural framing, plumbing, etc. These costs represent physical objects that will eventually become a part of the ADU.
Soft Costs
Soft costs refer to services that an owner might need, such as architectural and design services. Other soft costs might refer to infrastructure upgrades, such as upgrading the electrical and plumbing systems. These materials are needed to support the ADU, but do not become an actual component of the ADU itself.
Other soft costs refer to the fees paid to the city or county for the building permit. Additional insurance coverage can result in higher premiums, which would also be considered a soft cost. Savvy homeowners include these costs in their budget, instead of realizing at an inconvenient time that they may not have enough funds.
Hard Costs (Construction-Related Expenses)
- Foundation and Site Preparation (grading, retaining walls)
- Structural Engineering and Framing
- HVAC Systems
- Plumbing Systems
- Electrical Systems
- Interior and Exterior Finishes (paint, flooring, cabinets, roofing)
Soft Costs (Non-Construction Expenses)
- ADU Design & Architectural Plans
- Building Permits & Impact Fees
- Structural Engineering & Utility Upgrades
ADU Cost Comparisons: Roseville vs. Other California Cities
How does Roseville ADU costs compare to San Diego, Los Angeles, and the Bay Area?
Roseville, California provides the same benefits to ADU owners as some of the larger cities in California, but the price per square foot is considerably lower. Basic ADUs generally cost about the same from city to city, but large or elaborate ADUs can be significantly less expensive in Roseville.
ADU Cost Per Square Foot Comparison
- Placer County / Roseville: $315 – $500
- San Diego: $375 – $600
- Los Angeles: $250 – $600
- Bay Area: $350 – $650
Ready to build your dream ADU in Roseville or anywhere in Placer County?
Factors that make ADU construction more affordable in Placer County?
Legislation/Local Ordinances
California state laws regarding ADUs apply to the entire state, including Placer County. However, Placer County also eases parking requirements, setbacks, and provides more ADU services (like free, pre-approved designs).
Lower Building Costs
Building costs for an ADU in Placer County are among the lowest in the state, especially for ADUs with near the maximum square footage.
Excellent Financing Availability
California is very ADU friendly in general, but private companies are also very interested in providing financing. Placer County residents include low income earners and high income earners, so financing options are plentiful. Banks, owners, credit unions, and private equity groups want a piece of the business, and offer various financing methods as described above.
ADU Cost-Saving Strategies
- Choose a Garage Conversion or JADU (these are lower-cost ADU options compared to detached ADUs)
- Keep Your ADU Under 750 Sq. Ft. (avoids impact fees and most other school district fees)
- Use Pre-Approved ADU Plans (can save the owner 10% to 15% on design costs)
- Choose Cost-Effective Building Materials (use EnergyStar materials and follow Energy Star guidelines to save even more)
- Optimize Utility Connections (use the existing connections when possible to avoid unnecessary upgrades)
Are the Rules For ADUs the Same For Roseville, Rocklin, and Granite Bay as for the Rest of Placer County?
Generally, Roseville, Rocklin, and Granite Bay follow the same ADU laws as Placer County. However, there are a few key ordinances these cities enforce that may differ slightly from Placer County at-large. Here is a partial list of the key differences by city:
Rocklin
No Parking Requirement
Size Increase
Revised Setbacks
Rocklin separates detached and attached ADUs for setback purposes. Here are the setbacks Rocklin requires, based of the ADUs design:
- For detached ADUs, a minimum 4-foot side and rear setback applies. However, conversions of existing structures require no additional setback.
- Rocklin requires a five (5) foot side setback and a twenty (20) foot rear setback. However, with Planning Division approval the rear setback can be as little as ten (10) feet.
For more information, visit the website here: Rocklin City Website.
Granite Bay
These upgrades could require a large septic tank, and additional field drain lines to accommodate the extra occupants.
HOAs and Architectural Committees
However, at the end of the day, a homeowner in Granite Bay has the ministerial right to place an ADU on their property, as long as the relaxed rules are followed. However, most residents aim to work with, instead of against, these organizations, as the changes usually benefit the ADU property as well.
Fire Hazard Zones
Please note that if a Granite Bay property is in a fire hazard zone, or within the Tahoe Basin (in far northeast Placer), there could be extra rules to abide by. Tahoe area ADUs, for example, have special unit count limits under the Tahoe Regional Planning Agency( TRPA). Within Granite Bay city limits no unique ADU restrictions exist beyond standard Placer County code.
Ready to Build Your ADU in Roseville or Placer County?
Navigating ADU construction costs and financing options can feel overwhelming—but it doesn’t have to be. With careful planning, expert guidance, and the right financial strategy, adding an ADU to your property can become one of your smartest home-improvement investments.
RALH Construction is proud to be a veteran-owned, locally trusted company—and we’re one of the only design-build ADU contractors in the Roseville and Placer County area. From initial designs and permits to construction and final inspections, our team handles every step seamlessly, ensuring your project stays on schedule and within budget.
Whether you’re creating extra space for your family, generating rental income, or enhancing your property value, we’re here to turn your vision into reality.
Ready To Build? Our Team Is Ready.
Schedule your free consultation today!
Frequently Asked Questions About ADUs
How can I find out if my property is eligible for an ADU? (What are the local zoning laws or restrictions for building an ADU on my lot?)
Currently, laws are very friendly for building an ADU on your own property. If you have a backyard (and now even a front yard) you can an ADU! State laws supersede any city, county, and HOA restrictions.
What is the largest ADU I can build on my property? (Are there size or height limitations I should be aware of under local regulations?)
The largest detached ADU you can build on your property is 1200SQFT. If you are building an attached ADU, which is a JADU (Jr ADU) then it can not be 50% larger than the main residence’s square footage.
What permits and approvals do I need to build an ADU, and how long does it usually take to get them?
You will need to obtain a building permit to begin construction on your ADU. However, there are multiple requirements to get you there which include: fire approval letter, School letter, Sewer, water etc. It can take anywhere from 2-4 months to get your permit after initially filing.
Do I need to provide extra parking or meet any special requirements (like owner-occupancy rules) when adding an ADU?
It depends! This varies by the local jurisdiction that your property is located. In areas with already dense residential populations, this will always come up. For example, Cities are more strict in parking requirements rather than counties with bigger lot sizes. If you are in the City of Sacramento, Citrus Heights, or other areas with similar density you can expect to meet parking requirements.
How much does it typically cost to build an ADU, and what factors will affect the total project cost?
Building an ADU can cost anywhere from 175k all the way up to 400k+ depending on a lot. Some of the factors you should look into is how is the area that you are planning to use as the foundation for your ADU? Is it sloped? Does that require extensive excavation and grading work? Is the soil filled with rock and granite? Where are your utility tie connection points? What kind of design are you looking for: Spanish, Modern, Farmhouse?
As you can see, so many factors play into the final pricing of your ADU so no one number fits all.
What additional fees or “hidden” costs should I budget for (such as permits, utility hookups, or impact fees) when planning an ADU?
Fees that need to be budgeted for are plan check fees, impact fees if you are building an ADU greater than 749 SQFT, Fire Sprinkler and Solar Fees.
These will all depend on what your local jurisdiction will want, so it is best to work with an ADU builder who has experience and is well versed in this type of work.
What financing options are available to help pay for an ADU?
(Can I use a home equity loan, construction loan, or are there special ADU loan programs or grants?) Financing is one of the most crucial pieces to the puzzle when it comes to building your ADU. You can go about this a few ways, see bullets below;
- HELOC – Utilize the equity in your property and pull a line of credit to help finance your build.
- Cash Out Refi – Another way to utilize the equity in your property to help finance your ADU.
- Construction Loan – You can use a construction loan to build an ADU, yes you actually can. Although it has costs involved with it, this option may be best for investors or someone looking to build multiple ADU’s.
- Cash – If you have the resources available you can pay directly out of pocket.
What kind of return on investment can I expect from an ADU?
You can expect your property value to rise and earn a very strong rental income from your ADU. Although appraisers and the real estate market are still learning the value and how to appraise ADU’s, they still do add value to your property immediately. An average 2 bed 1 Bath can rent from $2,000- $2,700. Crazy, right? Well if you look at what apartments are costing you nowadays those numbers don’t sound too bad. Especially when you consider you are not worrying about sharing walls with your neighbors or walking up a flight of stairs with your groceries.
How long does it usually take to design and build an ADU from start to finish (including design, permitting, and construction)?
From start to finish, you are looking at a 6-9 month time frame. The construction process usually moves fairly quickly in comparison to obtaining plans/design/permit.
What are the main steps in the ADU construction process, and who handles each stage (design, permitting, inspections, construction)?
Here are the few main steps:
- Design – Working with a reputable Architect who has experience in ADU’s and local jurisdictions ensures this step goes smoothly.
- Permitting – Working with the planning and building department to meet all requirements needed to obtain your construction permit.
- Construction – Using a licensed General Contractor who will navigate the construction process which includes: scheduling, inspections, subcontractor management, material deliveries, recycling requirements, and much more.
Will building an ADU disrupt my daily life or bother my neighbors?
The reality is, when you are building your ADU your backyard turns into a short term job site. Like any job site you may have seen or driven by, there is material that needs to be stored, need to have temporary restrooms for all the workers, etc. That being said, it can be a disruption if expectations are not clearly defined. What we do here at Ralh construction is establish a barrier, usually throw snow fencing or something of that nature, so the homeowner can still have their privacy and space.
Do I need to upgrade my home’s existing utilities (like the electrical panel or sewer line) to support the ADU, and how are new utility connections handled?
Due to new code requirements, all electrical panels need to be upgraded to be able to provide power to the ADU and then the existing dwelling on the property.
For sewer and water tie ins, that is dependent on your property. If you are required to have Fire Sprinklers, then you may need to upgrade your water line to account for the amount of water that is needed for both structures. As far as sewer tie ins go, most times you will not need to update your sewer line (unless your structure is very old). However if you are on a septic system on your existing dwelling, you will need to either upgrade to a bigger tank or add a different septic system for the ADU.
What qualifications or credentials should I look for in an ADU contractor to ensure they’re qualified and reliable?
The qualifications and credentials you should be looking at - there is a few of them.
To begin, is your contractor local or from out town? I would almost always recommend working with a contractor from your local area, this will lead to them being very familiar with the inspections and requirements needed to ensure a smooth painless construction process.
Do they have examples of completed work? You don’t need to see a 100 projects completed, but at least being able to see photos of one or even walk a job in progress or a completed project (if available) is highly recommended.
Other things to look at, are there trucks wrapped with their company information? This shows they are proud of the work they do and hold true to their brand.
Last but not least, can you view this contractor as a teammate in your ADU journey? Construction has its ups and downs, no matter who you work with. Ensuring you are working with someone who has your best interest is CRUCIAL to project success.
How can I verify an ADU contractor’s reputation and trustworthiness before hiring?
You can look up the contractor and information about their license on the California State License Board website, check google reviews, view social media, and ask to see pictures of their portfolio.
What are some red flags that might indicate a contractor is not a good choice for my ADU project?
Some red flags that you should look out for when picking you contractor is the follows:
- Unlicensed – Run as fast as you can! If something goes wrong, the homeowner is held liable for all injuries/damages.
- No company branding
- Asking for a 50% deposit to get the project started – legally, it can only be 10% or $1000. Whichever comes first.
- No past reviews/Social Media/Internet Presence – these are your fly by night contractors, avoid these at all costs.
- Being unorganized as a contractor is a big red flag. Do they show up on time? Do they do the things they said? How can you trust someone to manage and organize your money and all the subcontractors if they are not organized themselves
- Lowest bid – they are lowest bid for a reason. Unethical practices and cutting corners are the only way they are beating out pricing.
Will my ADU contractor handle the design and permitting process, or do I need to hire an architect or designer separately?
It depends on who you work with! Some contractors only handle the construction process, leaving the design and permitting process on the homeowner.
At Ralh Construction, we handle all design, permitting, and construction required for your ADU. Our goal is to make this as seamless as possible for the homeowner.
What are the best layout and design features to maximize space in a small ADU?
(How can I make a studio or one-bedroom ADU feel more open and functional?)
There are a couple ways you can achieve maximizing your space for your ADU. One way would be to high ceilings, nine feet ceilings for example. This makes the structure feel much more open than what it actually is. Another way is to have vaulted ceilings, this is a great way to maximize space, especially for smaller units such as studios.
Can I customize the design and finishes of my ADU to fit my needs and style, or do I have to choose from pre-designed plans?
We can build to whatever design you have in mind! We also offer a pre-designed plan for those who want to keep the design process simple and move quickly.
PRO TIP: Hire an interior designer if choosing to do a custom design, this can save you thousands of dollars and potentially your marriage….
What energy-efficient and eco-friendly features should I consider for my ADU to reduce utility costs and increase sustainability?
All of the building materials and methods that are used are energy efficient and up to California building standards, meaning we have this covered for you! There are other ways to increase your energy efficiency such as higher rated insulation, using higher efficiency windows, and adding timers to switches to help avoid any lights being left on!
What’s the difference between a prefab (factory-built) ADU and a custom on-site built ADU, and which option might be better for my needs?
There are a few differences between building on site vs. fabricating off site. One of the main differences is the control of your design and footprint of your ADU. When building on site, you can determine what you want your ADU to look like however most Pre-Fab options, you are limited to design options.
Another thing to consider, Pre-Fab units still require all excavation, grading, and foundation work to occur. So although it may seem like there is less work involved, that is not the case.
