Fast, Reliable Home Additions & ADU Across Three Lakes
Home additions and ADU construction in Three Lakes, FL typically run $45,000-$130,000 for room additions and $90,000-$220,000 for detached ADUs, with most projects taking 4-8 months from permit to final inspection. We’re Groundwork Construction Co. of South Florida, and we build across the 33186 corridor regularly. Our crews know the local permit cycle, the Miami-Dade HVHZ product-approval process, and the groundwater conditions that catch out-of-county contractors off guard. If you’re adding space to a home off SW 137th Avenue, SW 120th Street, or anywhere in the Three Lakes community, call us at (844) 665-0162 for a free estimate.
Why Groundwork Construction Co. of South Florida Is Three Lakes’s Preferred Home Additions & ADU Company
We’ve worked on enough Three Lakes homes to know the rhythm of this area. The 1970s-1990s CBS construction, the flat lots with retention lakes, the way Miami-Dade inspectors scrutinize every roof-to-wall connection. That familiarity saves our clients time and rework.
Our Home Additions & ADU team doesn’t subcontract out the structural phases or source mystery materials. We’re the single-source contractor handling your project from footing to finish, with 50+ recognized brands across cabinetry, countertops, roofing, windows, doors, and ADU construction. You choose the brand, we handle the build.
Raymond Estevez, who leads Groundwork, has directed addition and ADU projects throughout Miami-Dade’s High-Velocity Hurricane Zone. He knows the difference between a permit package that sails through and one that gets held up for weeks over a missing NOA number.
We respond to Three Lakes inquiries within one business day, and we schedule site visits to understand your specific lot conditions before we quote. From driveway to roofline, one contractor handles every phase.
Our Home Additions & ADU Services in Three Lakes
ADU Site Prep & Utilities
Three Lakes’s flat Miami limestone terrain and high water table make site prep a specialized operation here. The porous Miami oolite bedrock sits just below the surface, which means foundation work for additions and ADUs can often anchor into solid rock at shallow depths-but the high water table requires dewatering during excavation, a step that is less critical in neighboring cities with deeper groundwater. On a recent ADU project off SW 137th Avenue, our crew had to contend with the shallow water table-within 18 inches of grade. We used a wellpoint system to keep the footer trench dry while pouring footings that tied directly into the Miami oolite, avoiding the need for deep piers. The homeowner’s existing CBS house from the 1980s also needed new hurricane ties and a reinforced roof-to-wall connection to pass Miami-Dade’s HVHZ inspection. We handle utility tie-ins, drainage design, and the dewatering plan as part of our standard scope.
New Detached ADU
A detached ADU in Three Lakes gives you rental income, multi-generational space, or a home office without touching your main structure. We build these stick-built or through our prefab partnerships with Abodu, Dvele, Mighty Buildings, and Boxabl. Prefab can compress the build timeline significantly, but every unit still needs HVHZ-compliant windows, doors, and roofing with active Miami-Dade NOA numbers. We manage that product-approval lookup so you don’t face permit delays. Built to spec, not to convenience.
Second Story Additions
Adding a second story to an existing Three Lakes home is one of the most complex projects we handle. The 1970s-1990s CBS homes in this area were built before the post-Andrew code overhaul, which means the roof-to-wall connections often won’t pass current HVHZ inspection without retrofit. We assess your existing structure’s capacity, design the lateral load path, and bring the original home into compliance as part of the addition scope. This isn’t optional in Miami-Dade. It’s the law, and we build it in from day one.
Garage Conversion ADU
Converting an existing garage to living space is a popular path in Three Lakes, where many homes have attached two-car garages that sit underutilized. We handle the slab moisture barrier, insulation, HVAC extension, and the required egress window. Pricing typically falls between $30,000-$80,000 depending on whether we’re extending utilities, adding a kitchenette, or reworking the roofline.
Room Additions & Junior ADU
Single-room additions and Junior ADUs-converting existing interior space with a separate entrance-work well for homeowners who don’t want exterior construction. We handle the permitting, the structural assessment, and the finish selections from our curated brand roster.
What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Three Lakes
We don’t lock you into proprietary products. For kitchen and bath components in ADU builds, we work with Kohler and Moen fixtures, Silestone and Caesarstone countertops, and cabinetry from KraftMaid and Wellborn. Every window and door we specify carries an active Miami-Dade NOA number before it hits your permit package. For roofing on second-story additions, we draw from GAF, CertainTeed, Owens Corning, IKO, Atlas, Tamko, and Boral. Our local supply relationships mean we’re not waiting weeks for HVHZ-rated materials to arrive from out-of-county distributors.
Common Home Additions & ADU Problems We See in Three Lakes Homes
- Settling or cracking from inadequate dewatering. Groundwater intrusion during footing excavation can wash out the soil matrix beneath your new addition. We specify wellpoint or sump dewatering on every Three Lakes site with a high water table, which is most of them.
- Permit delays from non-approved window and door specs. Specifying a beautiful Pella or Andersen unit that lacks a current Miami-Dade NOA number will stop your permit cold. We verify NOA status before submittal.
- HVHZ inspection failures on older CBS homes. The original roof-to-wall connections in 1970s-1980s Three Lakes construction rarely meet current code. We include retrofit hurricane ties and reinforced connections in every addition scope.
- Slab moisture issues in garage conversions. Original garage slabs lack the vapor barrier and insulation required for living space. We address this during conversion, not as a change order later.
Pricing for Home Additions & ADU in Three Lakes, FL
Here’s what homeowners in Three Lakes are actually investing for expanded living space:
| Project Type | Typical Range in Three Lakes |
|---|---|
| Home Addition | $45,000-$130,000 |
| ADU Construction | $90,000-$220,000 |
| Garage Conversion | $30,000-$80,000 |
Your final cost depends on square footage, foundation complexity (dewatering and rock excavation add scope), finish selections, and whether we’re bringing existing structure up to HVHZ code. We don’t guess. We visit your Three Lakes property, assess the site conditions, and deliver an itemized estimate. Estimates are free. Call (844) 665-0162 to schedule.
We Also Serve Cities Near Three Lakes
Our crews work throughout West Kendall and the surrounding communities. We regularly build in Three Lakes, The Crossings, Country Walk, The Hammocks, and Kendale Lakes. The same HVHZ expertise, the same product-approval discipline, the same single-source accountability.
Serving Three Lakes, FL - Our Local Coverage Area
We’re based in the Three 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.
FAQs - Home Additions & ADU in Three Lakes
Because Three Lakes’s water table sits within 18 inches of grade on many lots, and the Miami oolite bedrock lies just below the surface. Miami-Dade building officials require documentation showing how you’ll keep footings dry during pour and how you’ll anchor into or span the shallow rock. We include geotechnical assessment and dewatering plans in our standard Three Lakes proposals. Call (844) 665-0162 and we’ll explain what your specific lot requires.
You don’t have to fully retrofit the entire existing structure, but any work that touches the building envelope triggers upgrade requirements for the affected areas. Roof-to-wall connections, window and door replacements in the addition’s proximity, and structural ties between old and new must meet current HVHZ standards. We design the scope so you pass inspection without unnecessary demolition.
No. A garage conversion ADU requires converting the opening to a rated wall assembly with proper egress. The roll-up door assembly doesn’t meet residential energy, impact, or fire separation codes. We remove it, infill with CBS or frame construction to match, and install a code-compliant entry door and egress window. This is standard on every garage conversion we build in Three Lakes.
An NOA is Miami-Dade County’s product approval certification, issued only after independent testing proves a window, door, or roofing component can withstand HVHZ wind pressures and impact loads. Every product on your permit must have an active NOA number. We verify this before ordering. Using non-NOA products means permit rejection and costly substitutions mid-project.
Yes, if the existing foundation and walls can handle the additional load. We start with a structural assessment of your CBS walls and footing system. Most 1970s-1980s Three Lakes homes need reinforcement at the roof-to-wall connection and possibly at the foundation perimeter. We engineer the lateral load path and include all necessary retrofits in our build plan. Expand what’s possible, but build it to spec.
Ready to add space to your Three Lakes home? Call Groundwork Construction Co. of South Florida at (844) 665-0162 for a free, on-site estimate. We’ll assess your lot conditions, review your HVHZ compliance path, and deliver a clear scope with real numbers. One contractor, every phase.
Written by Raymond Estevez, Owner at Groundwork Construction Co. of South Florida, serving Three Lakes and Miami-Dade County.