What Does a Garage Conversion ADU Cost and Involve in Kendale Lakes?
A garage conversion ADU in Kendale Lakes transforms your existing garage into a permitted living space, typically adding 400-600 square feet of conditioned floor area. Most projects we handle here run 10-14 weeks from permit approval to final inspection, with costs ranging from $30,000-$80,000 depending on whether we’re working with a pre-Andrew CBS structure or a post-1992 rebuild. Call (844) 665-0162 and we’ll walk your specific garage on the next available day.
Homeowners in Kendale Lakes pursue this route for two clear reasons: the footprint already exists, and the permitting path through Miami-Dade is more straightforward than new detached construction. But “straightforward” doesn’t mean simple. Every garage conversion ADU here must reconcile the original structure’s wind-load capacity with current HVHZ standards, and that’s where the project gets interesting.
We approach this as part of a full Home Additions & ADU in Kendale Lakes scope, though many homeowners start with just the garage and expand later. Our Home Additions & ADU crew handles the structural, MEP, and finish phases under one contract. If you’re already thinking about interior finishes, homeowners often pair this with Cabinets & Countertops in Kendale Lakes for the kitchenette buildout, or with Backsplash, Tile & Flooring in Kendale Lakes to match the new living space to the main house.
How We Convert a Garage to an ADU - Stage by Stage
We break every garage conversion ADU in Kendale Lakes into five distinct phases. Here’s what actually happens, who decides what, and how long each stage takes.
Phase 1: Structural assessment and code determination (1-2 weeks). Before we touch anything, we determine whether your garage was built pre-Andrew or post-1992. This isn’t academic - it dictates the structural reinforcement scope, the wind-load calculations, and which edition of the Florida Building Code applies. We pull original permits where they exist, measure existing slab thickness, and test the roof-to-wall connections. You’ll decide at this stage whether to proceed with a full structural upgrade or a more limited retrofit if the existing frame can demonstrate compliance.
Phase 2: Design, MEP planning, and permit submission (3-5 weeks). This is where the garage stops being a garage. We design the kitchenette layout, locate the bathroom, and plan the mini-split HVAC zone. In Kendale Lakes, we almost always specify impact-rated windows and doors - even if the existing garage door opening is being infilled with framed wall, any new glazing must meet HVHZ requirements. We also map electrical service capacity; many 1970s-1980s panels need upgrading from 100-amp to 200-amp to handle the additional dwelling unit. You’ll approve fixture locations, material selections, and the final floor plan before we submit to Miami-Dade Building.
Phase 3: Demolition, slab prep, and rough construction (2-3 weeks). The garage door comes out, the slab gets assessed for moisture intrusion (common in this area due to the high water table), and we frame new interior partitions. If the existing slab is too thin or too cracked, we pour a floating slab over it with proper vapor barrier - we’ve learned not to trust existing garage slabs in Kendale Lakes to perform as residential floors without remediation. Rough plumbing and electrical go in, and we schedule the first inspection.
Phase 4: Dry-in, systems, and insulation (2-3 weeks). New roof ties get reinforced or replaced, impact-rated windows and doors install, and we close in with Miami-Dade-approved wall assemblies. We specify closed-cell spray foam or rigid foam board with proper drainage plane - the humidity here punishes fiberglass batts in exterior walls. The mini-split gets mounted, electrical finishes, and plumbing fixtures set. This phase ends with mechanical, electrical, and plumbing rough inspections.
Phase 5: Finishes, final inspection, and certificate of occupancy (2-3 weeks). Flooring, cabinetry, countertops, tile, paint, and final electrical/plumbing fixtures. We coordinate final inspections with Miami-Dade, address any corrections, and deliver your certificate of occupancy. You’ll do a walkthrough with our project lead and compile a punch list before final payment.
The Spec Choices That Move Your Garage Conversion ADU in Kendale Lakes
Every garage conversion ADU forces decisions that don’t have one “right” answer - just trade-offs between first cost, operating cost, durability, and daily experience. Here’s what our Kendale Lakes clients actually weigh:
- Slab strategy: overlay vs. replacement. An engineered floating slab with vapor barrier runs $4,000-$8,000 but solves the moisture issues we see constantly in western Miami-Dade garages. Full slab replacement with proper sub-base drainage doubles that but eliminates any risk of efflorescence or tile failure. Most clients choose overlay; we recommend replacement if the existing slab shows significant cracking or previous water staining.
- Window and door rating: impact vs. non-impact with shutters. Impact-rated units from PGT or CGI add $3,000-$6,000 to the package but require no storm preparation and satisfy HVHZ without additional documentation. Non-impact with rated shutters costs less upfront but demands annual maintenance and pre-storm deployment. For a rental ADU where you won’t be on-site to board up, impact-rated is the practical choice.
- Kitchenette scale: wet bar vs. full cooking. A wet bar with mini-fridge and microwave draws less permitting scrutiny and keeps MEP costs down. A full kitchen with range and oven requires commercial-grade ventilation, larger electrical service, and more square footage dedicated to cabinets and counters. We see this choice split evenly between clients building for family use versus rental income.
- HVAC: mini-split vs. extending central system. A dedicated mini-split runs $2,500-$5,000 and gives the ADU independent climate control - critical for rental metering. Extending the main house central system costs similar but creates shared utility complexity and often requires upsizing the main unit. Mini-split is our default recommendation.
- Bathroom location: preserving existing plumbing vs. new rough-in. If your garage shares a wall with existing wet spaces, we can often tie in with minimal trenching. Relocating to the opposite corner adds $2,000-$4,000 in plumbing and concrete cutting. The shallow limestone here makes trenching slower than in Broward County, so this decision has real schedule impact.
What Garage Conversion ADU Costs in Kendale Lakes, FL
Garage conversion ADU projects in Kendale Lakes typically fall between $30,000 and $80,000. Here’s what pushes a job toward the low or high end of that range, and what your written estimate includes.
| Cost Factor | Low-End Impact | High-End Impact |
|---|---|---|
| Existing garage condition | Sound structure, minimal cracking | Pre-Andrew frame, extensive spalling, slab replacement needed |
| Square footage | 400 sq ft (single-car) | 600+ sq ft (oversized two-car) |
| MEP complexity | Wet bar, no plumbing relocation | Full kitchen, new bathroom rough-in, 200-amp service upgrade |
| Finish grade | Standard cabinetry, LVP flooring, solid-surface counters | Custom cabinetry, tile or hardwood, stone counters (Silestone or Caesarstone) |
| Structural requirements | Post-1992 build, minimal reinforcement | Pre-Andrew CBS, full wind-mitigation retrofit, roof tie upgrades |
A written estimate from us includes structural assessment, permit fees, all materials, labor, inspections, and final cleanup. It does not include temporary relocation costs if you choose to vacate during construction, landscape repair from any necessary drainage work, or furniture and appliance purchases. We specify allowances for selections you haven’t made yet - flooring, fixtures, countertops - so you’re not surprised when you choose Caesarstone over laminate.
The single biggest variable we see in Kendale Lakes is the pre-Andrew vs. post-Andrew structural divide. A garage attached to a 1985 CBS home with original roof ties can add $8,000-$15,000 in structural reinforcement that a 1995 rebuild simply doesn’t need. We identify this in Phase 1 and price it transparently before you commit.
What Kendale Lakes Homes Specifically Do to This Job
Kendale Lakes sits in the western Miami-Dade flatlands that were ground zero for Hurricane Andrew’s 1992 destruction, leaving the community’s housing stock as a patchwork of pre-Andrew CBS homes needing wind-mitigation retrofits and post-Andrew rebuilds already engineered to the dramatically stricter Florida Building Code. Every garage conversion ADU here requires determining which generation of code the structure was built under before a single permit is pulled.
The surviving pre-Andrew homes - common north of SW 88th Street and throughout the original Kendale Lakes development - frequently still have original single-pane jalousie or aluminum windows, aging flat or S-tile roofs, and none of the impact-resistant glazing now required. When we convert a garage on one of these structures, we’re not just finishing interior space; we’re often upgrading the entire home’s wind-load path to satisfy Miami-Dade’s HVHZ enforcement, which treats any structural modification as a trigger for full compliance.
The local water table and limestone substrate create their own complications. Kendale Lakes’s position on the eastern edge of the Everglades means prolonged wet-season saturation from June through October, and the shallow Miami Limestone bedrock - sometimes just inches below topsoil - stops standard excavation cold. We’ve learned to plan garage conversion ADU schedules with weather buffers and to specify slab moisture mitigation as standard, not optional.
Permitting through Miami-Dade Building typically takes 4-6 weeks for garage conversion ADU plans, longer if the property is in a flood zone requiring additional elevation documentation. We handle this directly; you don’t need to navigate the online portal or interpret correction notices.
Serving Kendale Lakes, FL - Our Local Coverage Area
We’re based in the Kendale Lakes 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 Kendale Lakes
Most projects take 10-14 weeks from permit approval to certificate of occupancy, with permit submission and review adding another 4-6 weeks before construction starts. Pre-Andrew homes may extend this by 2-3 weeks if structural reinforcement is required. Call (844) 665-0162 and we can assess your specific timeline after a site visit.
Yes, absolutely. Miami-Dade County requires full building permits, mechanical permits, plumbing permits, and electrical permits for any garage conversion ADU, plus zoning verification that your lot allows the additional dwelling unit. We pull all permits as part of our scope; you never handle that paperwork directly.
Sometimes, but rarely completely. Most garage conversion ADU projects require at least electrical service expansion and new plumbing rough-in for the bathroom or kitchenette. If your garage already has a utility sink and adequate electrical, you might minimize MEP work, but full ADU standards - separate HVAC, kitchen facilities, and habitable-grade finishes - almost always require more than what’s there.
A garage conversion ADU in Kendale Lakes typically costs 30-50% less than new detached construction because the foundation, roof structure, and exterior walls already exist. New detached ADU construction in this market runs $90,000-$220,000. The trade-off is less design flexibility and the structural constraints of your existing garage.
We warranty our workmanship for one year from certificate of occupancy, with manufacturer warranties passing through on all materials and fixtures - typically 10 years on windows, lifetime on certain roofing components, and varying terms on appliances and HVAC equipment. We provide all warranty documentation at project closeout and assist with any manufacturer claims that arise.
Ready to Convert Your Garage in Kendale Lakes?
Call (844) 665-0162 for a free on-site estimate. We’ll walk your garage, determine your structure’s code generation, and deliver a written scope and price within 48 hours. No deposit required to schedule, and we only start when you’re clear on every line item.
Written by Raymond Estevez, Owner at Groundwork Construction Co., serving Kendale Lakes and South Florida.