Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
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AfterFast, Reliable Home Additions & ADU Across Three Lakes
A home addition or ADU in Three Lakes generally runs $45,000 to $130,000 for a room addition, and $90,000 to $220,000 for a detached new-build ADU, with garage conversions landing between $30,000 and $80,000. We schedule free estimates across the 33186 ZIP code, and a live person answers our phone at (877) 610-1318 when you call. Three Lakes was rebuilt largely between 1992 and 1996 under Miami-Dade’s post-Andrew codes, and that construction history shapes nearly every addition and ADU we quote here.
We know this area’s concrete block and stucco homes the way only a company that’s been working in Miami-Dade since 1998 can. The flat oolitic limestone shelf under Three Lakes means every slab pour, footer dig, and utility trench has to account for a seasonal water table that sits just 2 to 4 feet below grade in summer. That’s not generic Florida construction talk. That’s the difference between an ADU foundation that stays put and one that settles.
Why Barrett & Sons Construction Is Three Lakes’s Preferred Home Additions & ADU Company
Tom Barrett founded this company in 1998, and his sons run the crews. When you hire us for a Home Additions & ADU project in Three Lakes, the person who shakes your hand at the estimate is the same person you’ll see on-site most days. We’re not a franchise that dispatches strangers from a call center in another state. We answer our own phone, and we back every job with a written 90-Day Done Right Promise: if it’s not done right, one call brings Tom back.
Three Lakes homeowners ask us the same thing every week: will the crew actually show up, and will the price on paper match the final invoice? Both are fair questions, especially in a county where out-of-area contractors routinely get tripped up by the Miami-Dade Notice of Acceptance requirements and then hand the customer a change order to cover the re-order. Our answer is simple. Every scope, every allowance, every price change comes as a written change order before any work happens. The permit inspector works for you, not for me. That’s why I like him.
We hold strong local reviews from Three Lakes customers, and Tom publishes his name, address, and license number so you can look it up before you sign anything. Three Lakes homeowners don’t have to take our word for any of it. Ask anyone on your street, or look up the license number yourself.
Our Home Additions & ADU Services in Three Lakes
ADU Design & Permitting in Three Lakes
Every detached ADU in Three Lakes has to clear Miami-Dade’s HVHZ product approval and the county’s zoning review. We handle both. You won’t sit on hold with the building department wondering where your permit is. We pull the permit, we walk the inspection, and we bring the project to signed-off. A properly permitted ADU in the 33186 ZIP also protects your resale value, which matters on a $90,000 to $220,000 build.
Garage Conversion ADU in Three Lakes
Three Lakes has a deep stock of two-car garages on late-1980s and 1990s CBS homes, and converting one into a rental unit or in-law suite is often the most cost-effective ADU path at $30,000 to $80,000. The existing slab usually works, but we check for the shallow footer depth and the limestone substrate before we commit to anything. Miami-Dade requires NOA-rated windows and exterior doors on any conversion, so we spec those from day one instead of discovering the problem at inspection.
New Detached ADU in Three Lakes
Building a new detached ADU on a Three Lakes lot means dealing with the high summer water table during excavation and slab prep. We plan for active dewatering on almost every dig south of Kendall Drive. Your final price lands between $90,000 and $220,000 depending on square footage, finishes, and whether you add a full kitchen or a kitchenette. We’ll quote you line by line, in writing, before anything gets signed.
Junior ADU & Interior Conversion in Three Lakes
If you have a den, a bonus room, or an enclosed patio that never quite became living space, a Junior ADU conversion can turn it into a legal, rentable unit without the footprint of a new build. These jobs in Three Lakes typically run $45,000 to $130,000 depending on the plumbing and electrical scope. We’re also the team to call when the same house needs a Kitchen Remodeling in Three Lakes or a full Bathroom Remodeling in Three Lakes while we’re already in the walls.
What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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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
You should be able to look up every material that goes into your Three Lakes addition before you pay for it. That’s why we install brands with published specifications and real warranties: Schluter for waterproofing and tile systems, GAF for any roofing tied to a second-story addition, and Sterling for plumbing fixtures in ADU kitchens and baths. We don’t show up with mystery brands off a van. If a product carries a Miami-Dade NOA number, we verify it’s current before it goes on the truck.
Common Home Additions & ADU Problems We See in Three Lakes Homes
- Failed inspections from out-of-area product approvals. A contractor from outside Miami-Dade shows up with standard Florida-statewide-approved windows or roofing, and the inspector rejects them because they lack a current Miami-Dade NOA number. We see this happen to Three Lakes homeowners every season. The re-order pushes the project back weeks and the customer eats the cost.
- Water intrusion at the addition tie-in. Three Lakes’s CBS homes expand and contract differently than wood frame. When a new addition ties into an existing block wall, the flashing and waterproofing detail at that seam is where problems start. We treat that junction as a separate scope item, not an afterthought.
- Slab settlement from the shallow water table. The porous limestone under Three Lakes drains fast, but the summer water table sits close to grade. A footer that looks fine in February can heave or settle by August if the dewatering was skipped. We plan excavation around the water table, not around the dry season.
- Undersized electrical panels on pre-1996 homes. Homes rebuilt in the 1992-1996 window often carry 100-amp panels. Adding an ADU with its own appliances and HVAC can overload that. We check panel capacity on every quote and include the upgrade in writing when it’s needed.
Pricing for Home Additions & ADU in Three Lakes, FL
A room addition in Three Lakes runs $45,000 to $130,000. A new detached ADU runs $90,000 to $220,000. A garage conversion runs $30,000 to $80,000. A Junior ADU or interior conversion lands in the $45,000 to $130,000 range. What moves the number: the square footage, whether you need new foundation work, kitchen and bath count, whether the panel needs an upgrade, and the finish package you choose. We price in writing, by line item, before you sign. No allowances that aren’t on paper. No surprise invoices at the end. Call (877) 610-1318 for your free estimate.
We Also Serve Cities Near Three Lakes
Our Home Additions & ADU crews also cover Three Lakes and the surrounding southwest Miami-Dade communities: The Crossings, Country Walk, The Hammocks, and Kendale Lakes. If you’re just outside the 33186 ZIP, call anyway. No trip charge inside the county.
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
A home addition in Three Lakes typically costs $45,000 to $130,000, while a new detached ADU runs $90,000 to $220,000 and a garage conversion runs $30,000 to $80,000. The exact number depends on square footage, foundation work, finishes, and whether your electrical panel needs an upgrade. Call (877) 610-1318 for a written, line-item quote. Estimates are free.
No, not without your signature. Every scope, every allowance, every price change comes as a written change order before any work happens. We don’t surprise Three Lakes homeowners with end-of-job invoices. If we find something behind the wall, you’ll see it in writing and approve it before we touch it.
Yes, on every eligible job. Miami-Dade County requires permits and NOA product approvals for additions and ADUs in Three Lakes, and we pull them before work starts. The inspector works for you, not for me. We walk the inspection with you and don’t hide from the sign-off.
A garage conversion in Three Lakes typically takes 8 to 14 weeks once permits are approved. A new detached ADU runs 5 to 8 months including foundation work, framing, mechanicals, and finishes. Your written proposal will include a schedule with milestones so you know what’s happening and when.
Every addition and ADU we build in Three Lakes carries our 90-Day Done Right Promise, written on the contract. If something’s not right after we finish, one call brings Tom back to make it right. We also pass through the manufacturer warranties on every installed brand, from Schluter to GAF.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Miami-Dade County since 1998.