What Does a Garage Conversion ADU Cost and Take in Ojus?
A garage conversion ADU in Ojus turns your existing garage into a permitted living space, typically adding a kitchenette, full bath, sleeping area, and separate entrance. Most projects we run in Ojus finish in 10 to 16 weeks from permit approval, and the investment lands between $30,000 and $80,000 depending on what’s already there and what code requires. Call (844) 665-0162 and we’ll walk your specific garage, same week.
How We Convert a Garage to an ADU in Ojus
Every garage conversion ADU follows a five-stage sequence. We’ve refined this across Miami-Dade County, but the Ojus timeline stretches slightly because county plan review and HVHZ inspections don’t move on anyone’s schedule.
Stage 1: Site measure and feasibility (Days 1-5). We walk the garage with you, check ceiling height, slab condition, and whether the existing roof structure can carry insulation and drywall loads under current code. Most Ojus garages we see are 1950s-1970s construction with flat built-up roofs and low headroom. We flag whether we need to raise the ceiling plate, trench the slab for plumbing, or sister the rafters. You decide at this stage: full kitchen or kitchenette, shower stall or tub, and whether the existing garage door becomes a framed wall or a glass door system. We photograph everything and send you a written estimate within 72 hours.
Stage 2: Design and permit package (Weeks 2-6). Our draftsperson produces plans showing the new layout, electrical service upgrade if needed, plumbing rough-in, and HVHZ-compliant window and door specs. Because Ojus pulls permits through unincorporated Miami-Dade County, we file directly with the county Building Department, not a city office. This means no local plan reviewer to call for status, but it also means we know exactly which county inspectors cover the 33160 ZIP and what they flag on garage conversions. You approve the plans before we file; changes after submission cost you $200-$400 in revised drawings and delay the review queue.
Stage 3: Demolition and rough construction (Weeks 7-10). We strip the garage to block and slab, cut trenches for drain lines if the bathroom sits opposite the house main, and frame new interior walls. In Ojus, the Miami Limestone sitting 1-3 feet below grade often means rock-hammering for any utility trenching, and the shallow water table means we run dewatering pumps while we work. This isn’t optional, and contractors who quote without it hit change orders. You make your final selections now: flooring material, cabinet line, countertop surface, and fixture package.
Stage 4: Systems and envelope (Weeks 11-14). Licensed electricians upgrade the panel or subfeed, plumbers set roughs, and HVAC gets routed, usually as a mini-split since extending ductwork from the main house rarely meets capacity. We install impact-rated windows and an impact-rated exterior door, both carrying Miami-Dade NOA numbers, and insulate to current energy code. The county inspector checks rough electrical, plumbing, and framing before we close walls.
Stage 5: Finish and final (Weeks 15-16). Drywall, paint, flooring, cabinets, countertops, fixtures, and final electrical and plumbing trim. We run a punch walk with you, address the list, and call for final inspection. Once the county signs off, you have a permitted ADU with its own certificate of occupancy.
The Spec Choices That Move Your Garage Conversion ADU
These decisions separate a $35,000 conversion from a $75,000 one. Each has a real trade-off:
- Kitchenette vs. full kitchen. A wet bar with mini-fridge, microwave drawer, and single-bowl sink runs $3,500-$6,000. A full kitchen with full-size range, dishwasher, refrigerator, and 8-10 cabinets hits $12,000-$20,000. For a rental ADU, the full kitchen commands higher rent. For in-law use, the kitchenette often suffices.
- Slab-on-grade flooring. Luxury vinyl plank ($4-$7/sq ft installed) handles the moisture risk in Ojus slab construction better than engineered wood, which can cup. Tile ($6-$12/sq ft) is bulletproof but cold underfoot. We typically recommend LVP with a 6-mil vapor barrier beneath, specified in our scope so there’s no finger-pointing if moisture migrates.
- Bathroom configuration. A 32-inch shower stall with a wall-hung vanity and compact toilet fits in 25 square feet and costs $4,500-$7,000. A 5-foot tub with double vanity needs 45+ square feet and pushes $10,000-$14,000. In a standard 20×20 Ojus garage, every square foot matters.
- HVAC approach. A 12,000 BTU mini-split ($2,800-$4,500 installed) is the default. Extending the house’s central system usually requires a load calculation and often a larger condenser, which can add $6,000-$10,000. Most homeowners choose the mini-split for independent control and lower upfront cost.
- Garage door replacement. Framing in the opening with a standard wall and impact-rated window runs $3,500-$5,500. Installing a folding glass wall system for indoor-outdoor flow pushes $12,000-$18,000 but transforms the feel of the space.
Homeowners often pair a garage conversion ADU with interior upgrades to the main house. If you’re already living through construction, Cabinets & Countertops in Ojus can be sequenced alongside the ADU finish work, and Backsplash, Tile & Flooring in Ojus extends the same material palette through both spaces.
What Garage Conversion ADU Costs in Ojus, FL
| Project Element | Typical Range |
|---|---|
| Garage Conversion ADU (total project) | $30,000 - $80,000 |
| Basic conversion (kitchenette, shower bath, LVP, mini-split) | $30,000 - $45,000 |
| Mid-range conversion (full kitchen, tub bath, tile, upgraded cabinets) | $45,000 - $65,000 |
| High-end conversion (folding glass wall, premium cabinets, stone counters, full kitchen) | $65,000 - $80,000 |
Five variables push your number up or down:
1. Existing garage condition. A dry, plumb, square block garage with headroom over 8 feet starts cheap. A sagging flat roof, spalled concrete slab, or termite-damaged framing adds $4,000-$12,000 in structural repair before the conversion begins.
2. Plumbing distance. If the garage sits at the far end of the house from the main sewer line, we trench through Miami Limestone and install a sewage ejector pump. That adds $3,500-$6,500 versus a gravity drain run.
3. Electrical service capacity. Many 1960s Ojus homes still run 100-amp panels. Adding a kitchen and bath to the garage often requires a 200-amp upgrade and new service lateral, which runs $4,000-$7,500 depending on FPL coordination.
4. Material grade. Stock cabinets from a national line versus custom semi-custom, or quartz versus laminate counters, can swing the finish budget $8,000-$15,000.
5. Permit and inspection complexity. Unincorporated Miami-Dade County charges standard fees, but HVHZ compliance documentation for windows, doors, and roofing products requires manufacturer NOA letters we must submit with the application. Missing paperwork cycles the permit back two to three weeks.
Our written estimates include demolition, rough and finish construction, permits, and standard fixtures. They do not include FPL service upgrades, separate landscaping, or furniture. Call (844) 665-0162 for an exact quote on your garage, estimates are free.
What Ojus Homes Specifically Do to This Job
Ojus sits inside Miami-Dade County’s High-Velocity Hurricane Zone, and that changes every material choice in a garage conversion ADU. Every window, every exterior door, every structural fastener must carry a Miami-Dade Notice of Acceptance, a county-specific certification stricter than Florida state approval. Products legal a mile north in Hallandale Beach, which sits in Broward County outside HVHZ, are non-compliant here. We’ve seen out-of-area contractors spec standard vinyl windows and get red-tagged at rough inspection, costing homeowners six weeks and $3,000 in re-ordering.
The housing stock compounds this. Most Ojus garages we convert are attached to 1950s-1970s concrete-block ranch homes built to pre-Hurricane Andrew codes, many still carrying original single-pane jalousie windows and flat built-up roofs. Once you pull a permit for any renovation, current HVHZ impact-resistance and wind-load requirements trigger, turning what looks like a simple interior remodel into a significant envelope upgrade. That flat roof over the garage? It often needs re-decking and a new membrane rated for the uplift pressures. The original garage door? Replaced with a framed wall and impact-rated assembly.
Because Ojus is unincorporated Miami-Dade rather than its own municipality, permits pull through the county Building Department. The inspection queue, fee schedule, and plan-review contacts are county-wide. Contractors who know Aventura’s city building department but not Miami-Dade’s unincorporated process often mis-file or underpay, then wonder why their permit sits in “pending corrections” for three weeks. We file directly with the county office that handles Ojus and the 33160 ZIP, and we know which inspectors cover this corridor.
Moisture is the hidden variable. Miami Limestone sits 1-3 feet below grade with a shallow water table. Any slab trenching for plumbing runs into rock and groundwater. We specify vapor barriers and drainage details that Central Florida contractors often skip, because porous limestone wicks moisture straight into slab-on-grade construction. Skip it, and your new LVP floors cup in eighteen months.
If you’re considering this as part of a full property upgrade, see how a garage conversion ADU fits within Home Additions & ADU in Ojus. Our Home Additions & ADU crew also handles detached units and room additions when the garage isn’t the right solution.
Serving Ojus, FL - Our Local Coverage Area
We’re based in the Ojus 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 - Garage Conversion ADU in Ojus
Most garage conversion ADU projects in Ojus take 10 to 16 weeks from permit approval to certificate of occupancy. The county plan review adds 4 to 6 weeks before construction starts, so budget 14 to 22 weeks total from signed contract to move-in. Call (844) 665-0162 and we’ll check current county review times.
Yes, absolutely. Ojus is unincorporated Miami-Dade County, so you pull permits through the county Building Department, not a city office. The permit package must show HVHZ-compliant windows and doors with Miami-Dade NOA numbers, current electrical and plumbing codes, and energy compliance. Unpermitted work gets red-tagged at sale and can require full demolition.
You can keep electrical in place if the existing panel has capacity, but plumbing almost always needs relocation. A garage conversion ADU requires a kitchen sink and bathroom, and the existing garage slab has no drain lines. We trench the slab and run new supply and waste, which is standard scope, not an extra. The question is whether we hit gravity drain or need a pump.
The lowest-cost garage conversion ADU keeps the existing slab and roof structure, installs a kitchenette rather than full kitchen, uses a 32-inch shower stall, runs LVP flooring, and specs a mini-split for HVAC. That combination typically lands near $30,000. Cutting below that usually means skipping code-required items that fail inspection. Call (844) 665-0162 for an exact quote on your garage.
We warranty our workmanship for one year from final inspection. Manufacturer warranties cover the products we install, windows, doors, cabinets, fixtures, each on their own terms. Because we work with 50+ recognized brands across every category, you choose the warranty length and coverage level that matches your comfort, not ours. We document every warranty card and pass it to you at closeout.
Get a Free On-Site Estimate for Your Garage Conversion ADU in Ojus
We’ll walk your garage, check slab condition and headroom, and give you a written estimate with real numbers, no deposit required. Call (844) 665-0162 or fill out the form. Most Ojus homeowners get their estimate within 72 hours of the site visit, and we can usually start pre-construction planning while county permit review runs.
Written by Raymond Estevez, Owner at Groundwork Construction Co., serving Ojus and South Florida.