What a Garage Conversion ADU in North Fort Myers Actually Costs and How Long It Takes
A garage conversion ADU in North Fort Myers typically runs between $30,000 and $80,000, and most projects take 10 to 16 weeks from the first day of demolition to the final Lee County inspection. That price covers turning an existing attached or detached garage into a fully permitted, self-contained living unit with its own kitchen, bath, sleeping area, and separate entrance. The wide range depends almost entirely on whether we are working inside the existing footprint or cutting into the slab for new plumbing. Call (844) 638-7249 for a free, written estimate on your specific garage - and we’ll walk you through which end of that range your project lands on.
How We Convert a Garage Into an ADU: The Real Sequence
Every garage conversion ADU in North Fort Myers follows the same Lee County permit workflow, but no two garages are in the same condition. Here is what happens, stage by stage, so you know what to expect before we ever swing a hammer.
1. Site Walk and Permit-Ready Drawings (Days 1-10)
We start by measuring every inch of the garage - floor to joist, wall to wall - and checking the slab elevation against the current FEMA flood map for your parcel. North Fort Myers sits along the Caloosahatchee River, and post-Ian Advisory Base Flood Elevation requirements have caught more than a few homeowners off guard. If your garage slab sits below the required elevation, we discuss stem-wall or piering options that keep the project compliant without starting over. From there, our draftsman produces the floor plan, electrical layout, and plumbing riser diagram that Lee County requires. We submit the package directly to the Lee County Building Department’s satellite office - not the City of Fort Myers, which has no jurisdiction here - and track it through plan review. You pick your finishes during this window so materials are ordered before the permit clears.
2. Demolition and Slab Work (Days 11-18)
The garage door comes out first, and we frame the new exterior wall in its place - usually with a standard entry door and a set of windows sized to meet egress code for the sleeping area. If your conversion needs a new bathroom or kitchenette drain line, we cut the concrete slab, trench to the existing sewer lateral, and lay new PVC underground. This is the single largest cost variable in any garage conversion: a bathroom that backs up to an existing wet wall saves thousands; a bathroom on the opposite corner of the garage adds trenching, backfill, and a concrete patch. We schedule the rough-in inspection with Lee County before we pour anything back. For garages with a post-tension slab, we X-ray to map the cables before cutting - hitting a tension cable turns a two-day trench into a structural repair.
3. Rough-In: Electrical, Plumbing, HVAC, Insulation (Days 19-35)
With the slab patched and cured, our electrician runs a new subpanel, circuits for the kitchen appliances, bathroom GFCI, smoke/CO detectors, and dedicated outlets per current code. The plumber stubs out supply lines and vents. We install a mini-split heat pump for heating and cooling - ducted systems are rarely practical in a garage footprint, and a high-SEER mini-split handles Florida humidity far better than a window unit ever could. Walls get R-13 batt insulation, and we spray-foam the rim joists to meet the energy code. Lee County inspects the rough-in before we close anything up: framing, electrical, plumbing, and mechanical, all in one visit if we time it right.
4. Drywall, Trim, and Finishes (Days 36-50)
Drywall goes up, seams get taped and floated, and we spray texture to match the main house. This is where the space stops looking like a construction site and starts feeling like an apartment. We hang interior doors, set the baseboards and casing, and install the kitchenette cabinets and bathroom vanity. Flooring goes in last - usually luxury vinyl plank throughout, which handles North Fort Myers humidity without warping and cleans up easily after sandy feet come through the door. Paint, caulk, and final trim detail take about a week.
5. Fixtures, Final Inspection, and Turnover (Days 51-60+)
The plumber sets the toilet, sink, shower trim, and kitchen faucet. The electrician installs all switches, receptacles, light fixtures, and the panel directory. We schedule the Lee County final inspection - building, electrical, plumbing, and mechanical - and walk the inspector through the entire unit. Once we have the signed-off permit card and a certificate of completion, the ADU is legal to occupy. We do a final walkthrough with you, hand over the warranty paperwork, and make sure every door, drawer, and switch works the way it should.
What extends the timeline beyond 60 days? Post-Ian permit volume at Lee County is still elevated. If plan review is backed up, the clock pauses between Stage 1 and Stage 2 - and that is something no contractor can control. We submit as early as possible and keep the rest of the job moving once the permit is in hand.
The Options You Will Choose Between
A garage conversion ADU is not a one-size-fits-all plan. These are the real decisions our North Fort Myers clients make, and each one shifts the budget:
- Attached versus detached garage. An attached garage already shares at least one wall and the roofline with the main house, which simplifies utility connections and often keeps the cost closer to $30,000-$50,000. A detached garage is essentially a standalone building - running a new sewer lateral, water line, and electrical feeder across the yard pushes the job into the $50,000-$80,000 range, especially if we have to cut through a paver driveway or mature landscaping.
- Full kitchen versus kitchenette. A kitchenette with a microwave, under-counter refrigerator, and a small sink needs only two 20-amp circuits and a single drain. A full kitchen with a range, dishwasher, and garbage disposal requires a 50-amp circuit, vent hood ducting, and additional plumbing - adding roughly $3,000-$6,000 in electrical and plumbing labor before you pick the first appliance. Most North Fort Myers ADU owners choose the kitchenette; the ones planning to rent the unit long-term go full kitchen.
- Bathroom location inside the footprint. If we can tie the new bathroom drain into an existing waste line within 10 feet, the slab cut is small and the cost stays low. Every additional foot of trenching through concrete adds material and time, and if the garage floor is post-tensioned, the X-ray and cable-avoidance work is a flat-cost adder regardless of distance.
- Flooring and finish grade. Luxury vinyl plank throughout runs $4-$7 per square foot installed and holds up to humidity and foot traffic. Tile in the bathroom is standard. At the upper end, some homeowners spec engineered hardwood or polished concrete, which raises material cost but requires the same subfloor prep. We price each option line-by-line so you see the difference before you sign.
- Windows and natural light. A garage starts with zero or one window. Adding enough glazing to meet egress and make the unit feel habitable - usually two or three 3×5-foot impact-rated windows - runs $800-$1,200 per opening installed. North Fort Myers sits in a high-velocity wind zone, so every window we install carries a Florida Product Approval number; we will not use anything that fails the wind-missile test.
What a Garage Conversion ADU Costs in North Fort Myers, FL
A garage conversion ADU in North Fort Myers costs $30,000 to $80,000, with most projects landing between $40,000 and $60,000 for a standard one-bedroom, one-bath unit with a kitchenette. That price includes all Lee County permit fees, the stamped drawings, materials, labor, and the final inspections. The number on your estimate depends on four things: whether the garage is attached or detached, how far we need to trench the new drain line, whether the existing slab meets the current flood elevation, and the finish level you choose. A basic conversion with the bathroom backing up to an existing wet wall, an attached garage, and standard finishes comes in around $35,000. A detached garage on the far corner of the lot, requiring a full kitchen, a separate sewer tap, and upgraded finishes, can push past $70,000.
What is included in our written estimate: floor plan and permit drawings, the Lee County permit fee, demolition and debris removal, concrete cutting and trenching, all rough-in plumbing and electrical, the mini-split HVAC system, insulation, drywall and texture, doors and trim, flooring, the kitchenette or kitchen cabinetry and countertops, the bathroom vanity and shower, fixtures, paint, and the final inspection walk. What is typically not included: impact windows beyond the minimum egress requirement, major structural upgrades to bring an older garage up to current wind-load code, and any separate meter or utility-service upgrade the power company might require for a rental unit. We price the project line by line so you see exactly where every dollar goes. Call (844) 638-7249 for a free on-site estimate - we will measure, check the slab, and hand you a number you can take to the bank.
What North Fort Myers Homes Specifically Do to This Job
North Fort Myers is unincorporated Lee County, which changes the entire permitting path for a garage conversion ADU. We submit to the Lee County Building Department, not a municipal office, and the reviewers enforce the post-Ian code amendments that now require elevation certificates for parcels inside the revised AE and VE flood zones. If your garage slab sits low, you are not simply converting it - you are either building on a stem-wall extension or accepting that the ADU cannot have a sleeping area below the Advisory Base Flood Elevation. We have seen this trigger a full site-built code review even on lots inside manufactured-home communities along the Pine Island Road corridor, where the owner expected a simpler HUD pathway and instead got a county-level structural review.
The housing stock here tells the story. Many North Fort Myers garages we convert belong to 1970s and 1980s CBS single-family homes on fill lots near canals. Those garages were built as open carports that got enclosed decades later, often without a permit. The slab might not have a vapor barrier underneath, the walls may lack shear paneling, and the electrical is frequently tapped off a single 15-amp circuit that also feeds the laundry room. We budget for those discoveries. When we open a wall and find unpermitted wiring, we pull it, run new home runs back to the panel, and bring everything to current code before the rough-in inspection. That surprises people - but here, it is the rule, not the exception. A garage conversion ADU in North Fort Myers done properly is as much a correction project as it is new construction, and our 730-Day Done Right Promise means we do not cover up what should have been fixed.
This kind of work often runs alongside other interior upgrades - homeowners pairing a garage conversion with new Cabinets & Countertops in North Fort Myers or fresh Backsplash, Tile & Flooring in North Fort Myers to carry the same finish level through the house. When the project scope expands, it falls under our Home Additions & ADU in North Fort Myers work, and our Home Additions & ADU crew is built to handle the full scope without subcontracting every trade to someone we have never met.
Serving North Fort Myers, FL - Our Local Coverage Area
We’re based in the North Fort Myers area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
Frequently Asked Questions About Garage Conversion ADU in North Fort Myers
Yes. Every garage conversion ADU in North Fort Myers requires a building permit from the Lee County Building Department, and the plans must be stamped by a Florida-licensed architect or engineer. The county reviews for structural, electrical, plumbing, mechanical, and zoning compliance - skipping the permit is not an option, and unpermitted work will get flagged when you sell the property or file an insurance claim. We handle the entire permit package, from drawings to final sign-off, so you never deal with the county directly.
Most garage conversion ADU projects in North Fort Myers take 10 to 16 weeks, assuming the Lee County permit queue is running at a normal pace. The actual construction - demolition through final inspection - is 8 to 10 weeks. The variables are the permit review time (which can add 2-6 weeks during busy periods) and any structural surprises we find when we open the walls or cut the slab. We give you a realistic schedule at the estimate stage and update it if the county timeline shifts.
Only if you do not need a bathroom or kitchen sink in the ADU - and a habitable dwelling unit requires at least a bathroom by code. A half-bath needs a toilet and a sink, both of which require a drain line. If the garage shares a wall with an existing bathroom, we can often tie into that drain without a long trench. If the garage is on the far side of the house, we are cutting the slab. We walk every North Fort Myers client through the plumbing layout before the estimate is final so you know exactly what the site demands.
What does a garage conversion ADU include versus a full Home Additions & ADU in North Fort Myers project?
A garage conversion ADU works within the existing garage footprint - four walls and a roof already in place. A full home addition or detached ADU starts from bare ground and requires a new foundation, framing, roof, and all utility runs from scratch, which is why new-construction ADUs run $90,000-$220,000. The garage conversion is the more cost-effective path when the structure is already sound and the slab elevation checks out.
Every garage conversion ADU we build is covered by our 730-Day Done Right Promise. If something is not right, we make it right - no short-window exclusions, no fine print that expires the month after we leave. That includes workmanship on framing, drywall, flooring, plumbing, electrical, HVAC, and finishes. Manufacturer warranties on appliances and fixtures are separate and passed directly to you at turnover. Call (844) 638-7249 and we can walk through exactly what the warranty covers on your specific project.
Get a Free, Line-by-Line Estimate for Your Garage Conversion ADU in North Fort Myers
If you have a garage sitting empty - or full of boxes you have been meaning to sort - let us show you what it could be. We will come out, measure the space, check the slab, talk through the layout, and hand you a written estimate with every line item spelled out. No vague numbers, no change orders mid-job, no surprises when the permit comes back. Call (844) 638-7249 to schedule your free on-site estimate for a garage conversion ADU in North Fort Myers. A live person answers, day or night.
Written by Derek Hollenbeck, Owner at Groundwork Construction Co., serving North Fort Myers and Southwest Florida.