What a Garage Conversion ADU Costs and Involves in Greenacres City
A garage conversion ADU in Greenacres City turns your existing attached or detached garage into a permitted, livable dwelling unit with its own kitchenette, bathroom, sleeping area, and separate entrance. Most projects we handle here run 8 to 14 weeks from permit approval to final inspection, with budgets typically landing between $30,000 and $80,000 depending on whether the structure needs electrical service upgrades, plumbing rough-ins, or wind-mitigation work to meet current Palm Beach County standards. Call (844) 665-0162 and we’ll walk your specific garage with you to pinpoint where your project likely falls in that range.
How We Convert a Garage Into an ADU - Start to Finish
We’ve refined this into five clear stages so homeowners know exactly what’s happening and when they need to make decisions. Here’s how a typical garage conversion ADU unfolds in Greenacres City.
Stage 1: Feasibility and as-built documentation (1-2 weeks). We measure the garage precisely, photograph existing conditions, and pull the original permit history from Palm Beach County if it’s available. You’ll decide right here whether you want a full kitchen or a kitchenette, whether the bathroom needs a tub or just a shower, and whether you’re keeping the existing garage door opening as your ADU entrance or framing in a conventional doorway. That last choice affects your wind-load rating significantly in this county.
Stage 2: Design and permit submission (3-6 weeks). Our drawings address Florida Building Code wind resistance for the converted envelope, tie-down connections for the roof-to-wall junction, and energy compliance for the conditioned space. Greenacres City falls under Palm Beach County’s unincorporated jurisdiction for permitting, which means plan review goes through the county’s central office. You’ll select your window and door specs during this stage - impact-rated products are not legally required for every opening in an existing garage conversion, but many homeowners opt for them because insurers offer meaningful discounts.
Stage 3: Demolition and rough construction (2-3 weeks). We strip the garage interior to studs, remove or permanently secure the overhead door, frame new interior partitions, and modify the slab for plumbing drains if you’re adding a bathroom or kitchenette. In Greenacres City’s 1960s-1980s CBS ranch homes, the garage slab is often poured lower than the main house floor, so we assess whether to raise it or step the interior threshold - a decision that affects both cost and accessibility.
Stage 4: MEP rough-in and insulation (2-3 weeks). Electrical service gets heavy scrutiny here. Many original garage circuits are 15-amp and ungrounded; an ADU needs 20-amp grounded circuits, dedicated HVAC power, and often a subpanel or service upgrade. Plumbing rough-in for a kitchenette and bathroom runs through the slab or along interior walls. We insulate to current energy code, which in Palm Beach County means R-30 ceiling and R-13 walls minimum.
Stage 5: Finishes, fixtures, and final inspection (2-3 weeks). Drywall, flooring, cabinetry, countertops, and fixture installation happen here. The county inspects for code compliance, we address any punch items, and you receive a certificate of occupancy that formally establishes the unit as a legal ADU. That document matters for rental agreements, refinancing, and resale.
The Spec Choices That Shape Your Garage Conversion ADU
Every decision below moves your final number and how the space lives. We lay out the honest trade-offs so you’re choosing with eyes open.
- Garage door conversion method: Remove entirely and frame in a stud wall with a conventional entry door - most common, most weathertight, adds $2,500-$4,500. Or convert to a faux-door architectural wall that retains the exterior visual rhythm - better for HOA compliance, roughly $1,000 more. Some homeowners keep a functional overhead door with a living-space-rated insulated model; this preserves future garage reversion but sacrifices wall space and insulation performance.
- Kitchenette vs. full kitchen: A kitchenette with a two-burner cooktop, compact refrigerator, and single-bowl sink runs $4,000-$7,000 installed. A full kitchen with standard appliances, dishwasher, and 6-8 feet of cabinetry pushes $12,000-$18,000. For rental ADUs in Greenacres City, the kitchenette satisfies most tenant expectations; for in-law use, families usually want the full kitchen.
- Bathroom configuration: A 3/4 bath with shower, toilet, and vanity fits most garage footprints and costs $8,000-$14,000. Adding a tub or expanding to a full bath with separate tub and shower adds $4,000-$7,000 and eats floor area. In the 20-foot-deep garages common here, a tub often forces compromises on bedroom or living space.
- Slab and moisture management: Greenacres City’s shallow water table means garage slabs can wick moisture. We offer a vapor barrier and epoxy sealant system ($1,500-$3,000) before flooring, or a full floating subfloor assembly ($4,000-$6,000) that creates an air gap. The subfloor is overkill for most conversions but essential if you’re putting down engineered hardwood or LVP you want to last.
- HVAC approach: A dedicated mini-split ($3,500-$5,500) is quiet, efficient, and doesn’t load your main house system. Extending central ductwork from the main house ($2,000-$4,000) is cheaper upfront but often struggles with balanced airflow and creates code complications for fire separation between dwelling units.
- Countertop and fixture grades: For the kitchenette or bath vanity, laminate countertops with basic chrome fixtures keep budgets tight. Upgrading to quartz - Silestone or Caesarstone are what we spec most often - with Kohler or Moen faucets adds $2,000-$4,000 across the unit but dramatically improves durability and rental appeal. We don’t push these upgrades; we show samples and let the use case decide.
What Garage Conversion ADU Costs in Greenacres City, FL
Garage conversion ADU projects in Greenacres City typically range from $30,000 to $80,000. Where you land depends on five factors we assess during our first site visit.
| Cost Driver | Low-End Scenario | High-End Scenario |
|---|---|---|
| Existing garage condition | Sound slab, dry walls, functional electrical | Moisture damage, failing slab, knob-and-tube wiring |
| Size and layout | Single-car (240 sq ft), simple rectangle | Double-car (400+ sq ft), L-shape or with storage nook |
| Utility extensions | Kitchenette, 3/4 bath, mini-split HVAC | Full kitchen, laundry hookups, central HVAC tie-in |
| Structural modifications | Door infill only, no roof changes | Raising slab, re-framing roof for clerestory or dormer |
| Permit and code compliance scope | Standard conversion, existing wind mitigations pass | Full secondary water barrier, tie-down upgrades, impact openings |
A written estimate from us itemizes demolition, rough construction, MEP, finishes, and permit fees. What it does not include: temporary relocation costs if you’re living in the main house during construction, separate utility meter installation if you want the ADU billed independently, and landscaping repair from any exterior work. We flag these during our walkthrough so you’re not surprised.
What Greenacres City Homes Specifically Do to This Job
Greenacres City’s housing stock shapes every garage conversion ADU we bid here. The dominant single-story CBS ranch homes from the 1960s-1980s were built before Florida’s post-2004 hurricane code overhaul, which means the garage is often the weakest link in the wind-resistance chain. We’ve opened garages in Greenacres City neighborhoods where the roof-to-wall connection was three toenails and a prayer - perfectly normal for 1978, completely inadequate for a permitted dwelling unit in 2026.
That reality drives cost and timeline in ways contractors from outside South Florida routinely miss. When we pull a permit for a garage conversion ADU on a pre-2004 home, Palm Beach County inspectors typically require us to bring the entire roof-to-wall connection up to current standard, not just the converted portion. That means hurricane straps or clips, secondary water barrier verification, and often re-nailing the roof deck. It’s not optional, and it’s not the inspector being difficult - it’s the 170 mph design wind speed requirement for this county, full stop.
The shallow water table on this former agricultural land also means moisture management isn’t an afterthought. We’ve cut into garage slabs in Greenacres City and found standing water six inches down. Any contractor who doesn’t probe for that before quoting is either inexperienced or planning to change-order you later.
Homeowners here are also navigating insurance pressure that doesn’t exist inland. Because Home Additions & ADU in Greenacres City projects often coincide with wind-mitigation retrofits, we coordinate our structural work with roofers and window crews so you’re not paying for access twice. Our Home Additions & ADU crew handles this sequencing weekly.
Many clients finishing a garage conversion ADU also update the main house kitchen or bath while we’re mobilized. If that describes your situation, we can scope Cabinets & Countertops in Greenacres City or Backsplash, Tile & Flooring in Greenacres City under the same project management and timeline.
Serving Greenacres City, FL - Our Local Coverage Area
We’re based in the Greenacres City 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 Greenacres City
Most projects run 8 to 14 weeks from permit approval to certificate of occupancy, with permit review itself adding 3 to 6 weeks depending on Palm Beach County’s current backlog. The variance comes down to whether your existing structure needs structural upgrades and how quickly you make finish selections. Call (844) 665-0162 and we can give you a tighter range after seeing your garage.
Yes - absolutely, and attempting this without one risks fines, insurance denial, and forced demolition. Greenacres City is unincorporated Palm Beach County, so permits route through the county’s Building Division and require plans showing compliance with the Florida Building Code, energy code, and zoning for accessory dwelling units. We handle the entire permit package as part of our service.
If your garage already has a sink or utility connections, you may be able to repurpose them, but most conversions require new plumbing rough-in for a bathroom and kitchenette, plus electrical upgrades to 20-amp grounded circuits and dedicated HVAC power. The existing 15-amp garage circuit and hose bib rarely suffice for a legal dwelling unit. We assess this on our first walkthrough and tell you exactly what’s reusable.
A garage conversion ADU is almost always less expensive than new detached construction because you’re working within an existing footprint and foundation. Our garage conversions in Greenacres City start around $30,000, while detached ADU construction typically runs $90,000 to $220,000. The trade-off is that a detached unit offers more design freedom and often rents for more; a garage conversion preserves yard space and moves faster.
We warranty our workmanship for one year from certificate of occupancy, and all materials carry their manufacturer warranties - typically 10 years for cabinets, lifetime for Kohler fixtures, and 10-15 years for mini-split systems. We register warranties in your name and provide documentation at project closeout. For exact coverage on your specific material selections, ask during your estimate walkthrough.
Ready to See What Your Garage Can Become?
We’ll walk your garage with you, assess the existing structure against Palm Beach County’s current code requirements, and deliver a written estimate with itemized pricing and a realistic timeline. No pressure, no deposit required to get the numbers. Call (844) 665-0162 to schedule your free on-site consultation for a garage conversion ADU in Greenacres City.
Written by Raymond Estevez, Owner at Groundwork Construction Co., serving Greenacres City and South Florida.