Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Before
After
Before
After
Before
AfterFast, Reliable Home Additions & ADU Across Miami Beach
Home additions and ADU construction in Miami Beach typically runs $53,100-$153,400, with detached ADUs starting around $106,200 when you factor in dewatering, elevated foundations, and Miami-Dade wind-load engineering. That’s the honest range before anyone steps foot on your property. We’re Barrett & Sons Construction, and we’ve built additions across this barrier island long enough to know that a bid that ignores the water table under your lot isn’t a bid, it’s a guess. For dedicated Miami Beach Roofing, we bring that same island-specific expertise. Call (877) 610-1318 for a written estimate that accounts for what’s actually under your house.
Why Barrett & Sons Construction Is Miami Beach’s Preferred Home Additions & ADU Company
Tom Barrett started this company in 1998, and he still answers his own phone. That matters in Miami Beach, where homeowners have learned the hard way that a contractor who quotes from a mainland office without ever putting a shovel in island soil doesn’t know what they’re bidding. Our Home Additions & ADU team has worked across South Beach, Mid-Beach, and North Beach, and we coordinate permits with the same city departments your neighbors deal with every week.
Since we’re a local owner-operated outfit, the crew members who show up carry the Barrett name. Tom’s sons run the crews, and they’re on-site most days, not checking in from a call center. Every price change comes as a written change order before any work proceeds, because the allowance that isn’t on paper is a surprise waiting for a date. That’s how we’ve kept Miami Beach homeowners coming back for nearly three decades.
Our Home Additions & ADU Services in Miami Beach
ADU Design & Permitting
Designing an ADU in Miami Beach means working with the city’s floodplain regulations, historic district overlays, and the post-Andrew wind-load standards that demand 170+ mph design pressures. We handle the full permit package, including the dewatering plans that Miami Beach requires for any excavation below the 18-24 inch water table common across the island. You’ll get a design that clears the building department the first time, not a resubmission cycle that costs you months.
Garage Conversion ADU
Converting a garage into living space in Miami Beach usually falls between $35,400 and $94,400, depending on whether you’re in a 1940s Art Deco structure or a 1960s concrete-block MiMo building. The older stock often hides Dade County Pine framing, which is so dense it dulls saw blades and requires pre-drilling, so labor estimates from mainland contractors regularly run short. We know to look for it before we write the scope, not after the first cut.
New Detached ADU
A new detached ADU in Miami Beach starts around $106,200 and goes up from there, because you’re building on a barrier island where a proper foundation means elevation, piles, or both. Salt-laden air off the Atlantic and Biscayne Bay attacks concrete and steel faster here than anywhere inland, so we spec materials and coatings with that specific environment in mind. The result is a structure built for Miami Beach’s conditions, not a generic plan dropped onto island soil.
Junior ADU & Interior Conversion
Interior conversions, like turning a ground-floor bonus room or underused garage wing into a junior ADU, often work within existing walls and avoid some of the site prep costs. In Miami Beach’s older buildings, that also means working around the historic fabric rather than against it. We coordinate with any historic district requirements so your conversion adds value without triggering a compliance fight.
Planning a bigger project? We also handle Kitchen Remodeling in Miami Beach and Bathroom Remodeling in Miami Beach, so your addition and the spaces inside it stay consistent. One crew, one scope, one written contract.
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.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Miami Beach
We build additions and ADUs with products you can look up, not mystery brands off a van. Our Miami Beach projects regularly include PGT impact-rated windows, engineered for the high wind loads this island faces, and Simonton and CGI Windows & Doors - Miami Beach lines where the design calls for them. We keep our supply relationships local, so lead times don’t stall your permit clock. When you’re building 200 feet from the ocean, the window brand matters more than the brochure.
Common Home Additions & ADU Problems We See in Miami Beach Homes
- Water table surprises during excavation. Across much of Miami Beach, you hit water at 18-24 inches, which means continuous dewatering from day one. Contractors who don’t plan for it stop work and ask for more money.
- Corroded rebar in mid-century concrete. The 1950s and 1960s MiMo buildings in Mid-Beach and North Beach are losing their original rebar to salt-air carbonation faster than inland structures, so addition tie-ins require careful structural assessment.
- Dade County Pine in pre-war frames. South Beach homes from the 1930s and 1940s are often framed with this near-petrified native wood, which dulls blades and can’t be nailed without pre-drilling. A bid that ignores it runs over on labor.
- Street grade shifts from sea-level-rise work. Miami Beach’s ongoing infrastructure program is raising road grades 1-2 feet and adding pump stations, so your property’s relationship to the street may change mid-project. We coordinate with the city’s current grid, not last year’s map.
Pricing for Home Additions & ADU in Miami Beach, FL
On this island, a typical room addition lands between $53,100 and $153,400. A garage conversion runs $35,400-$94,400, while a new detached ADU starts at $106,200 and can reach $259,600 for larger builds. What moves the number in Miami Beach is dewatering, elevated foundation requirements, wind-load engineering, and historic district compliance, things mainland contractors often leave out of their initial bids. We don’t. Every scope, every allowance, every price change arrives as a written change order before work happens, and every completed job is backed by our 90-Day Done Right Promise. Call (877) 610-1318 for a free estimate with real numbers for your specific lot.
We Also Serve Cities Near Miami Beach
Beyond our Miami Beach work, we take on projects in Isle of Normandy, North Bay Village, Miami, and Miami Shores. If you’re within a short drive of the island, we’ll bring the same written-scope approach and the same crew. Call (877) 610-1318 and ask for Tom.
Serving Miami Beach, FL - Our Local Coverage Area
We’re based in the Miami Beach 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 Miami Beach
Once permits are approved, we can typically begin on-site work within 2-4 weeks, depending on our current schedule and your project’s dewatering and foundation requirements. Miami Beach’s permit process runs on the city’s timeline, not ours, but we help move it along with complete submittals the first time. Call (877) 610-1318 to discuss your start window.
Yes, we work throughout the city, including 33139 (South Beach), 33140 (Mid-Beach), 33141 (North Beach), and 33109. We’re familiar with the different building codes, historic overlays, and lot conditions in each, so the estimate you get reflects your actual neighborhood, not a county average.
Yes, generally by 15-25%, because island construction requires dewatering, elevated foundations, stronger wind-load engineering, and often historic district compliance. A project that runs $90,000 in Miami may run $110,000-$135,000 in Miami Beach due to these site-specific requirements. We’ll show you exactly where the money goes in writing.
Not without your signature. Every scope change, allowance adjustment, or unexpected condition arrives as a written change order before any work proceeds. If it’s not on paper, it doesn’t happen, and we don’t hit you with a surprise invoice at the end.
Yes, on every eligible job, including dewatering plans, floodplain approvals, and historic district reviews. The permit inspector works for you, not for us, and we welcome the oversight. Call (877) 610-1318 for a free estimate on your Miami Beach addition or ADU.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Miami Beach and surrounding communities since 1998.