6 Best ADU Builders in Jacksonville – 2026

Most Jacksonville homeowners researching accessory dwelling units start with the wrong number. The figure that circulates locally is 750 square feet, but the ordinance actually caps an ADU at the lesser of that or 25% of the principal dwelling’s gross floor area. On a 2,400 square foot house, those two tests land in the same place. On a 1,600 square foot house, the real ceiling is 400 square feet, and several models marketed across Florida stop being options entirely.

For those interested in residential real estate exposure without a construction project, Ark7 offers fractional interests in professionally managed rental-property series, with shares starting as low as $20, subject to offering availability and eligibility.

This guide profiles six builders serving the Jacksonville market, plus one additional contractor worth inquiring with, compiled from publicly available company information as of 2026. Pricing, timelines, and license status change quickly, so verify credentials through Florida DBPR before signing.

Key Takeaways

• Jacksonville legalized ADUs in most residential zones through Ordinance 2022-448-E, the “Keeping Our Families Together Act.”
• Jacksonville generally limits an ADU to the lesser of 25% of the principal dwelling’s gross floor area or 750 square feet. The percentage rule can make the maximum smaller, not larger.
• Jacksonville Beach, Neptune Beach, Atlantic Beach, and Baldwin do not fall under this ordinance.
• Florida SB 48, which would have restricted local owner-occupancy requirements, died in Messages on March 13, 2026 and is not law. The current statutory framework is Florida Statute §163.31771.
• Florida Statute §193.703 authorizes counties to provide an assessment reduction for qualifying quarters occupied by a parent or grandparent age 62 or older.
• All permits route through the JaxEPICS system.
• Ark7 lets investors purchase shares in property-specific rental-property series, starting as low as $20, subject to offering availability and eligibility.

How This List Was Compiled

This list was assembled from publicly available company information rather than a scoring model, and no ranking is implied by the order below. Companies were compared on construction methodology, published pricing, licensing, and Jacksonville service coverage. One entry is listed separately because its published materials describe commercial rather than residential ADU work. Company-published pricing, project counts, and experience figures are labeled as such throughout. Verify licensing through Florida DBPR and confirm current pricing directly before contracting.

Jacksonville ADU Rules to Understand First

• Where ADUs are allowed: Ordinance 2022-448-E opened most residential zones to ADU construction as an accessory use subject to criteria. Four beach and outlying municipalities are excluded.
• The size test: Generally the lesser of 25% of the principal dwelling’s gross floor area or 750 square feet, subject to applicable zoning requirements. Run the percentage calculation before assuming 750.
• Setbacks: These vary by applicable zoning and ADU provisions. Confirm the parcel-specific requirement with Jacksonville Planning or Jacksonville Code §656.403 rather than relying on a general figure.
• Owner-occupancy: Confirm the current Jacksonville ordinance before assuming both units may be rented, since the state bill that would have restricted local requirements did not pass.
• HOA covenants: City approval does not necessarily override enforceable HOA covenants or deed restrictions.
• Permitting: All applications are processed through JaxEPICS, and builders with documented JaxEPICS history can help avoid resubmissions.
• Tax reduction: A county may provide the §193.703 assessment reduction; it is not automatic statewide, and eligibility requires homestead property, qualifying construction, and continued qualifying occupancy.

6 ADU Companies Operating in Jacksonville for 2026

1. Jax Tiny Homes (Local Stick-Built Specialist)

Service Area: Jacksonville, Ponte Vedra Beach, St. Augustine Beach, Fernandina Beach, Fleming Island, Orange Park

Type: Stick-Built, Site-Framed

License: Florida Certified Building Contractor CBC1269596

Starting Price: $85,000 and up, per company materials

Timeline: Company-stated 5 to 10 months from deposit to handover

Note that the CBC prefix denotes a Certified Building Contractor rather than a Certified General Contractor, which carries a CGC designation. Recheck the license before hiring, since status and expiration change.

What Sets Jax Tiny Homes Apart:

• Local Jacksonville focus with JaxEPICS familiarity
• Studio at roughly 400 sq ft, one-bedroom at roughly 600 sq ft, plus garage conversions and pool house units
• Company-advertised 5-star Google rating; BBB accredited
• Its roughly 1,000 square foot two-bedroom model would not qualify as a Jacksonville ADU without documentation showing how it meets the applicable size limit

2. Sunshine State Professional Services Inc. (Tri-County Design-Build)

Service Area: Nassau, Duval, and St. Johns counties

Type: Design-Build

Primary Office: 528 S 8th St, Unit 1, Fernandina Beach, FL 32034

Jacksonville Office: 8638 Philips Hwy, Suite 03 and 04, Jacksonville, FL 32256

Phone: (904) 517-2427

Timeline: Company-stated 5 to 8 months to move-in ready

Founded in 2015, the company states its structures are engineered for winds up to 180 mph. This is a product rating, not a universal requirement: Jacksonville applies the Florida Building Code, and design wind speed depends on location and risk category. A current Jacksonville worksheet identifies 125 mph west and 130 mph east of the city’s demarcation line for Risk Category II structures.

What Sets It Apart:

• Detached cottages, garage conversions, attached granny flats, custom plans
• Company-advertised 5/5 on Angi and 5.0/5 on Yelp
• Google Guaranteed, IICRC Certified, and BBB Accredited
• 3D rendering before construction

3. Mesocore (Factory-Built Modular)

Service Area: Statewide Florida including Jacksonville

Type: Modular Manufacturer

Headquarters: West Palm Beach, FL

Phone: (561) 386-7252

Model E: 410 square feet, 1BR/1BA, factory price $129,000 including solar and battery; installed turnkey $155,000 to $189,000

The 10-day installation figure covers on-site assembly only. Design, permitting, factory production, site work, utility connections, and inspections extend the total schedule considerably.

What Sets It Apart:

• Approximately 10-day on-site installation after permits and site prep
• Integrated 6kW solar array with dual 10 kWh lithium-ion batteries
• MEP systems certified by Intertek
• Additional costs beyond base price: delivery and crane $3,000 to $5,000, site prep and foundation $5,000 to $15,000, utility connections $3,000 to $10,000, on-site finish work $15,000 to $30,000

4. Goshen Tiny Homes (Site-Built Masonry)

Service Area: Jacksonville, Tampa, Miami, Orlando, St. Petersburg, West Palm Beach, Sarasota

Type: On-Site Block Construction

License: Florida Certified Residential Contractor CRC1335198

Timeline: Company-stated 10 to 16 months from contract to move-in

Goshen states that its units are site-built masonry structures rather than HUD-code manufactured homes. Property classification for appraisal or tax purposes depends on legal status, permitting, construction standard, title, and permanent attachment rather than material alone, so request documentation rather than assuming a classification.

What Sets It Apart:

• Ground-up, on-site block construction
• 14 models with 28+ floor plans
• Fixed-price contracts and a no-approval-no-charge policy

5. Florida Made Tiny Homes (Shell to Turnkey Tiers)

Service Area: Statewide Florida including Jacksonville, St. Augustine, Daytona Beach, Gainesville

Type: On-Site Block Construction

Pricing: Catalog upon request

Florida Made offers three build tiers, letting capable homeowners trade labor for savings at the shell level.

What Sets It Apart:

• Shell option providing structure for owner finishing
• Shell+ option including drywall and flooring
• Full turnkey option with all finishes
• Company-advertised 30+ years of building experience, with in-house design and permit coordination

6. First Coast Construction USA Inc. (Duval County Focus)

Service Area: Jacksonville, Duval County

Type: General Contractor

Address: PO Box 47105, Jacksonville, FL 32247

First Coast Construction provides ADU home additions, detached ADUs, and garage conversions, handling permits, design, and construction.

What Sets It Apart:

• Duval County concentration
• Full permit, design, and construction handling
• Limited public information is available, so verify contact details, license status, and references before proceeding

Other Contractors to Inquire With

Auld & White Constructors LLC

Address: 4168 Southpoint Pkwy., #101, Jacksonville, FL 32216

Phone: (904) 296-2555

Auld & White has operated in Northeast Florida for nearly 40 years. The Jacksonville Daily Record ranked the firm No. 3 in its April 2026 Top Contractors ranking, reporting approximately $230.17 million in 2025 local revenue, and the Jacksonville Business Journal’s 2026 list identifies it as the No. 1 tenant-improvement contractor on the First Coast.

Its current materials describe a commercial construction firm focused on new construction, healthcare, interiors, renovations, and tenant-improvement work. It is listed separately because residential ADU services are not established in its published materials. Contact the firm to confirm whether it takes on residential ADU work.

How to Choose the Right ADU Builder

• By build method: Site-built masonry creates a permanent improvement and avoids delivery constraints; modular compresses the on-site phase; stick-built framing suits owners matching an existing house.
• By how much you want to do yourself: Shell packages let capable homeowners finish interiors and lower the entry point, while turnkey contracts cover everything through certificate of occupancy.
• By permitting support: Ask whether the builder has documented JaxEPICS history, since permit resubmissions are a common source of delay in Duval County.
• By coverage: Nassau and St. Johns counties are served by Sunshine State; Duval by Jax Tiny Homes and First Coast; and statewide delivery by Mesocore, Goshen, and Florida Made.

Questions to Ask Any Jacksonville ADU Builder

• What is 25% of my principal dwelling’s gross floor area, and what does that allow me to build?
• What setback applies to my specific parcel under Jacksonville Code §656.403?
• Is your Florida license active, and does the category, CBC, CGC, or CRC, cover my project scope?
• Do you have documented JaxEPICS permit history in Duval County?
• Is your quote fixed-price or cost-plus, and how are change orders priced?
• Can you provide lien releases from subcontractors at each payment milestone?

Financing an ADU in Jacksonville

• Home equity options: HELOCs draw funds as needed during construction at variable rates.
• Cash-out refinance: Replaces an existing mortgage with a larger loan. Compare the blended cost against alternatives, since replacing a low-rate mortgage can increase total borrowing costs.
• Construction-to-permanent: Interest-only during the build, converting at completion.
• Personal loans: Typically 3 to 7 year terms, suitable for smaller projects.
• Cost planning: Vendor-cited ranges place new detached ADUs at $165,000 to $310,000 and above, garage conversions at $60,000 to $145,000, and modular installed at $90,000 to $210,000, with cost per square foot from $155 to $305. These come primarily from ADU vendors rather than independent permit, bid, or appraisal data.
• Soft costs: City permit and plan review of roughly $3,200 to $5,000 and impact fees of roughly $1,300 to $2,000 per vendor estimates, plus site preparation and utility connections.

Comparing ADUs and Fractional Real Estate

Building an ADU can create rental-income potential and may add value to a property, though the amount varies substantially by location, construction quality, legal status, and comparable sales. It also requires substantial upfront capital, months of project management, and ongoing landlord responsibilities.

ADU considerations:

• Vendors estimate roughly $1,100 to $2,200 monthly for one-bedroom units. Build any projection from current comparable listings in your area rather than a vendor range.
• Gross rent yield is not a return. An ADU renting for $1,600 monthly produces $19,200 in annual gross rent, about 10.4% of a $185,000 construction cost before expenses, vacancy, financing, taxes, insurance, maintenance, and management.
• A permitted ADU may add value, but the amount should be assessed by a qualified local appraiser rather than assumed.
• Where available, the §193.703 assessment reduction may not exceed the lesser of the increase in assessed value resulting from qualifying construction or 20% of the property’s total assessed value as improved. Construction cost and assessed-value increase are not necessarily the same figure.

How fractional investing compares:

For those who prefer fractional real estate exposure rather than developing and managing an ADU directly, Ark7 is another model to consider:

• Shares in property-specific rental-property series from $20, subject to offering availability and eligibility
• Potential monthly cash distributions, when available and subject to property performance, expenses, reserves, and offering terms
• Professional management without landlord responsibilities
• Exposure across multiple properties and markets rather than one local property
• No construction risk or permit timelines to manage
• Potential access to secondary trading, subject to holding periods, legal and state restrictions, platform availability, and market liquidity. Liquidity is not guaranteed.
• Ark7 IRA options support Traditional or Roth accounts, subject to IRA rules, custodian fees, and individual circumstances

An investment in an offering constitutes an investment in a particular series, not in Ark7 or the underlying assets. These are speculative securities involving substantial risks, including illiquidity, lack of diversification, and complete loss of capital.

Conclusion

Jacksonville’s builder market covers stick-built specialists, masonry contractors, modular manufacturers, and shell providers. What separates a workable project from a stalled one is usually settled before any of them are contacted: the size your principal dwelling permits, the setback your parcel carries, and whether your HOA covenants allow an accessory structure at all.

Why Jacksonville Stands Out for ADU Projects

• Broad zoning eligibility: Ordinance 2022-448-E opened most residential zones to ADUs as an accessory use.
• Large suburban lots: Mandarin, Southside, Fleming Island, and Orange Park offer space for detached construction.
• Steady tenant demand: NAS Jacksonville and Naval Station Mayport contribute consistent housing interest.
• Centralized permitting: All permits route through the JaxEPICS system.
• Possible tax relief: Florida Statute §193.703 authorizes counties to provide an assessment reduction for qualifying multigenerational units.

Investor Tips for Jacksonville ADU Projects

Calculate 25% of your principal dwelling’s gross floor area first, since that number, not 750 square feet, is often the real ceiling. Confirm parcel-specific setbacks with Jacksonville Planning rather than a builder blog, because they determine whether a unit fits at all. Verify contractor licenses through DBPR and check the category, since a CBC and a CGC authorize different scopes of work. When modeling returns, keep gross rent yield and actual return separate: annual rent divided by construction cost ignores vacancy, maintenance, insurance, taxes, management, and financing. Get HOA approval in writing before spending on permits or design, since city approval does not resolve private covenants.

For those who prefer residential real estate exposure without a construction project, Ark7 offers shares in rental-property series starting at $20 per share, subject to offering availability and eligibility.

Frequently Asked Questions

How large can my ADU actually be in Jacksonville?

Jacksonville generally limits an ADU to the lesser of 25% of the principal dwelling’s gross floor area or 750 square feet, subject to applicable zoning requirements. The percentage test frequently controls: a 1,600 square foot house yields a 400 square foot ceiling, not 750. Properties in adjacent jurisdictions, including Nassau County and St. Johns County, maintain separate regulations. Confirm your parcel’s specific limit with Jacksonville Planning before commissioning design work.

Can I get a property tax reduction for housing a parent in my ADU?

Possibly. Florida Statute §193.703 authorizes counties to provide a reduction in assessed value for qualifying living quarters occupied by a parent or grandparent age 62 or older. A county may provide this reduction, so it is not automatic statewide. Eligibility also requires homestead property, qualifying construction or reconstruction, and continued qualifying occupancy. Where available, the excluded value may not exceed the lesser of the increase in assessed value resulting from the qualifying construction or 20% of the property’s total assessed value as improved. Confirm availability and application procedures with the Duval County Property Appraiser.

What do the different Florida license prefixes mean?

Prefixes indicate scope. CBC denotes a Certified Building Contractor, CGC a Certified General Contractor, and CRC a Certified Residential Contractor. Jax Tiny Homes, for example, operates under CBC1269596, a Certified Building Contractor license. Search the Florida Department of Business and Professional Regulation’s online verification system by contractor name, business name, or license number to confirm active status, check for disciplinary actions, and verify the category matches your project scope. Never rely on a contractor’s word alone.

What if my HOA denies my ADU even though the city approved permits?

City approval does not necessarily override enforceable HOA covenants or deed restrictions, and whether a specific restriction is valid depends on the governing documents and applicable law. Before investing in plans or permits, request written confirmation from your HOA regarding accessory structure policies. Many planned communities in Ponte Vedra, Nocatee, and newer developments prohibit ADUs entirely or require architectural review board approval.

Do I need to provide parking for my ADU tenant?

Jacksonville’s ADU ordinance addresses parking based on zone and lot configuration, and many residential zones require one additional off-street space per ADU, though waivers may be available. Street parking does not typically satisfy the requirement. Discuss parking early in design, since adding it later can increase costs and may not be feasible on smaller lots. Confirm the requirement for your parcel with Jacksonville Planning.

Neither Ark7 nor Ark7 Properties is a broker-dealer or an investment adviser. Dalmore Group LLC, a registered broker-dealer and member FINRA/SIPC, located at 525 Green Place, Woodmere, NY 11598, is the broker-dealer of record for Ark7, an issuer direct offering. Neither Ark7 nor Dalmore makes recommendations or provides advice about investments, and nothing here should be construed as a recommendation for any security. An investment in an offering constitutes an investment in a particular series and not in Ark7 or any of the underlying assets. Investments on the Ark7 platform are speculative and involve substantial risks, including illiquidity, lack of diversification, and complete loss of capital. Cash distributions are not guaranteed and are subject to property performance, expenses, reserves, and offering terms. Past performance is no guarantee of future results. This article is for informational purposes only.