What a Garage Conversion ADU Costs and Entails in Iona, FL
Converting a garage into an ADU in Iona typically runs between $45,000 and $130,000 and takes 12 to 22 weeks from design to final inspection. The wide price spread hinges on whether you’re finishing out an existing enclosed garage with minimal structural changes or undertaking a full conversion that involves trenching new plumbing, upgrading electrical service, and lifting slab elevations to meet Lee County’s current flood requirements. Call (844) 638-7249 for a project-specific estimate. We’ll walk you through exactly what your garage needs. No guesswork, just a clear number and a schedule.
The Real Sequence of a Garage Conversion in Iona
We follow five distinct stages on every Iona garage conversion, and knowing them upfront helps you plan around the natural bottlenecks. The process isn’t complicated, but it is sequential. Skipping ahead on a permit while framing waits for an inspection costs time, not saves it.
Stage 1: Feasibility and the Lee County permit pathway. Before any design work begins, we pull your property’s flood zone designation and assess whether the existing garage slab meets current Base Flood Elevation requirements. For many 1970s and 1980s canal-front homes in Iona, it doesn’t. If your conversion triggers Lee County’s substantial improvement threshold (improvements exceeding 50% of the structure’s assessed value), the entire building may need to be elevated, which shifts the project scope dramatically. We handle this evaluation in the first week and give you a binary answer: standard conversion or elevation-triggered rebuild. A marine engineer’s seawall certification may also be required if you’re on a finger canal, and we line that up early so it doesn’t stall your permit review.
Stage 2: Design and material selection. Once we know the structural and elevation parameters, our design team draws the floor plan, the electrical layout, the plumbing rough-in, and the window and door schedule. This is where you choose your finishes: flooring type, kitchenette cabinet line, countertop material, bathroom tile, lighting fixtures, and the door style. We source everything through our established brand partners, so lead times are predictable. Most Iona homeowners complete selections within 10 days. We provide a fixed-price quote at this stage, not a range.
Stage 3: Demo, slab work, and rough-in. This is the loudest 2 to 4 weeks of the project. We gut the garage interior down to the studs and slab, trench for sewer and water lines if you’re adding a bathroom or kitchenette, frame interior walls, and run new electrical circuits back to the panel. In Iona, many older homes still have 100-amp service. A garage conversion with a mini-split, kitchenette, and bathroom usually demands a 200-amp upgrade, which we coordinate with LCEC. If the slab needs to be raised even a few inches to satisfy flood code, this is when it happens. We schedule rough-in inspections with Lee County before any drywall goes up.
Stage 4: Insulation, drywall, and finishes. After the rough-in passes, we insulate to current Florida Building Code standards, hang and finish drywall, install flooring, set cabinets and countertops, hang interior doors, and trim out the electrical and plumbing fixtures. This phase runs 3 to 5 weeks depending on the square footage and the number of wet rooms. The mini-split HVAC system goes in during this window. We keep the space weather-tight throughout, which matters during southwest Florida’s afternoon thunderstorm cycle. An exposed roofline during August can saturate fresh drywall in minutes, so we sequence open-ceiling work for early mornings.
Stage 5: Final inspections and walkthrough. Lee County requires a structural final, an electrical final, a plumbing final, and, for canal-front properties that triggered the seawall review, a sign-off from the marine engineer. We schedule all four concurrently to compress the timeline. The typical Iona garage conversion closes with a 90-minute walkthrough where we test every outlet, run every faucet, cycle the mini-split, and hand you a digital warranty packet. Your 730-Day Done Right Promise is active from the moment we hand you the keys.
Spec and Material Choices That Shape the Finished Space
Most garage conversions in Iona land somewhere between a studio guest suite and a one-bedroom apartment with a full bath and a kitchenette. The choices you make in these categories determine both the usability of the space and the final cost.
- Flooring. Luxury vinyl plank handles Iona’s humidity and occasional canal-side dampness better than engineered hardwood. Tile is cooler underfoot and nearly indestructible, but costs more in material and labor. Both work. We typically steer Iona homeowners toward LVP with a thick wear layer because it’s forgiving of slab imperfections and won’t warp if a mini-split condensate line drips.
- Kitchenette configuration. A wet bar with a sink, undercounter fridge, and microwave sits at the lower end. A full kitchenette with a two-burner cooktop, vent hood, dishwasher, and a small island pushes the price up considerably because it requires a gas or 240V line and a grease-trap compliant vent. Lee County classifies the latter as a second kitchen, which may bump your permit into a different occupancy category.
- Bathroom scope. A three-quarter bath (shower, toilet, vanity) is the standard inclusion. Adding a tub moves plumbing and floor-structure costs upward. In Iona, many garage slabs lack the depth needed for a tub drain without cutting and repouring a section of the slab, so we walk you through the cost difference honestly before you commit.
- Windows and doors. Every new opening in a garage conversion in Iona must meet the Florida Building Code’s wind-load requirements for the High-Velocity Hurricane Zone. We install impact-rated windows and doors, not standard residential units. The brand we spec depends on the opening sizes and your budget, but every product carries a Miami-Dade NOA. The garage door itself typically gets replaced with a solid wall or a impact-rated French door assembly. That single change often represents $4,000 to $9,000 of the total job cost.
- HVAC. Tying into the main home’s central system is rarely practical for a detached or semi-detached garage. We install a ductless mini-split sized for the square footage. It’s efficient, quiet, and doesn’t require cutting into existing ductwork. For larger conversions, a small central unit with a short duct run may make more sense, and we’ll price both options during design.
What a Garage Conversion ADU Costs in Iona, FL
A straightforward garage conversion ADU in Iona that assumes an intact slab, accessible electrical panel, and no flood-elevation trigger starts around $45,000. A high-end conversion with bathroom and kitchenette additions, new impact openings, slab cutting for plumbing, a 200-amp service upgrade, and permitting on a canal-front lot with seawall certification requirements can exceed $130,000.
The five variables that move the number:
- Slab condition and elevation. A level slab at or above Base Flood Elevation is the cheapest starting point. A slab that’s too low or has spalling from decades of salt air and garage chemicals adds $8,000 to $25,000 in concrete work.
- Plumbing distance. If the main sewer stack is 40 feet away on the opposite side of the house, trenching across the lot adds cost. If it’s within 10 feet of the garage wall, the job is simpler and cheaper.
- Electrical service capacity. Homes in Iona built before 1990 often carry 100-amp panels. A service upgrade to 200 amps adds $2,500 to $4,500. It’s not optional if you’re adding a mini-split, kitchenette appliances, and a bathroom circuit.
- Impact-rated openings. Replacing a single garage door with a code-compliant impact wall and window runs $4,000 to $9,000. Adding multiple windows or a sliding door increases the line item proportionally.
- Seawall certification and marine-engineering review. Unique to Iona’s canal-front lots. If Lee County flags your permit for a seawall cert, plan on $1,500 to $3,000 for the engineer’s inspection and report, plus 2 to 4 weeks of review time.
Every estimate we write is a fixed-price quote. It includes all materials, labor, permit fees, engineering stamps, and a project timeline. It doesn’t include hidden change orders or vague line items. If the Lee County plan reviewer requires something we didn’t anticipate, we bring it to you with a written explanation before we do the work. That’s how upfront pricing is supposed to function.
What Iona Homes Specifically Do to a Garage Conversion
Iona sits squarely in the storm-surge corridor that Hurricane Ian carved through the Caloosahatchee estuary in 2022, and that single event reshaped every permit desk in Lee County. Because Iona is unincorporated, all garage conversion permits run through the Lee County Building Department, not a municipal office. The volume of post-Ian substantial-improvement reviews has created a compliance environment that out-of-area contractors routinely misread. If your garage was damaged during Ian and the county has already flagged the property, a conversion may trigger a full elevation requirement even if the improvement itself seems modest. We navigate that determination before you spend a dollar on design.
The housing stock here is predominantly 1970s through 1990s concrete-block construction on slab, and many of the original slabs sit below the current Base Flood Elevation. On the finger canals that drain toward the Caloosahatchee, that elevation gap is often 18 to 30 inches. Converting a garage on one of these lots isn’t just a finish-out job. It’s a structural coordination with Lee County’s floodplain manager, sometimes a marine engineer, and always a wind-load calc for every new opening. We’ve done enough post-Ian work in Iona to know which canal-front streets, from the McGregor Boulevard corridor down to the side streets off Winkler, trigger the extra review and which don’t.
For Iona homeowners considering a garage conversion as part of a broader property upgrade, this work often fits inside a full Home Additions & ADU in Iona plan. Our Home Additions & ADU team coordinates the conversion alongside any other improvements so the permit package stays coherent. And if you’re already opening walls and running plumbing for the ADU, many homeowners choose to update the adjacent laundry room or kitchen with Cabinets & Countertops in Iona or new Backsplash, Tile & Flooring in Iona while the crew is on site. Coordinating the trades once saves real money. Covering Iona has taught us that post-Ian rebuilds reward sequencing. We structure the schedule so no trade sits idle waiting on another.
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Frequently Asked Questions About Garage Conversion ADU in Iona
Twelve to twenty-two weeks, depending on whether the slab needs structural modification and whether Lee County requires a seawall certification or elevation review. The actual construction phase runs 8 to 12 weeks. The front-end permit and engineering stage adds 2 to 6 weeks. We give you a week-by-week schedule at contract signing so you know when the space will be habitable. Call (844) 638-7249 to get a timeline specific to your garage.
Yes. Every garage conversion in unincorporated Lee County requires a building permit, and if you’re adding a bathroom or kitchenette, you’ll need separate plumbing and electrical permits. If your property sits in a FEMA flood zone and the project crosses the substantial-improvement threshold, a floodplain review is also required. We pull every permit under our license and handle the inspections from rough-in through final. You don’t file paperwork. We do.
You can, and it keeps the cost at the lower end of the range. A garage conversion that stays a dry studio with no bathroom or kitchenette avoids slab trenching, sewer tie-in, and a plumbing permit. The trade-off is long-term utility: an ADU without a bathroom limits its use as a rental or guest suite. We lay out both options during the feasibility stage with the exact cost difference so you can decide with the numbers in front of you.
Plan on $80,000 to $130,000 for a fully plumbed garage conversion ADU in Iona with a three-quarter bath, kitchenette, impact-rated openings, a mini-split HVAC system, and a 200-amp electrical service upgrade if your panel needs it. The permit fees, engineering stamps, and any slab elevation work are included in that range. The final number depends on the finish level you choose during design. Estimates are free. Call (844) 638-7249.
Our 730-Day Done Right Promise covers every garage conversion we complete in Iona. If something isn’t right within two full years of the final walkthrough, we fix it. That includes the framing, drywall, electrical, plumbing, flooring, cabinetry, paint, and all installed fixtures. It’s one of the longest workmanship guarantees in residential construction, and it’s written into your contract, not just mentioned in a sales conversation. The manufacturer warranties on windows, doors, flooring, and appliances run separately and typically span 10 years to lifetime.
Get a Fixed-Price Estimate for Your Iona Garage Conversion
If you’re ready to understand exactly what your garage can become and what it will cost, call (844) 638-7249. A live person answers, 24/7. You’ll describe your garage, we’ll ask a few questions about the slab, the electrical panel, and your wishlist, and we’ll schedule a free on-site estimate. You’ll get a written quote with a line-by-line scope and a project timeline. No pressure, no vague numbers, no voicemail black hole. Just a clear path from a parked car to a finished living space.
Written by Derek Hollenbeck, Owner at Groundwork Construction Co., serving Iona with fixed-price construction since 2014.