Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Fast, Reliable Home Additions & ADU Across Surfside
A home addition in Surfside typically runs $45,000 to $130,000, while a detached ADU generally lands between $90,000 and $220,000 depending on size, foundation work, and site conditions. On a barrier island with shallow groundwater and county-level permitting quirks, the real cost driver is rarely the square footage. It’s what’s under the slab and what the county wants done about it. Call (877) 610-1318 and we’ll walk your lot before we talk numbers.
We know the difference between Town of Surfside review and Miami-Dade County plan review, and we know which one applies to your parcel. That matters more than most homeowners realize when they start pricing an addition or ADU in Surfside’s 33181 zip code.
Why Barrett & Sons Construction Is Surfside’s Preferred Home Additions & ADU Company
We’re the company where the owner’s name is on the truck and his sons run the crews. Tom Barrett founded Barrett & Sons Construction in 1998, and the way we build in Surfside hasn’t changed: every permit gets pulled, every price change comes as a written change order before work starts, and every job ends with a written 90-Day Done Right Promise.
Surfside homeowners call us because we answer the phone, we show up when we say we will, and we don’t hand over a surprise invoice at the end. The permit inspector works for you, not for me. That’s why I like him. If something isn’t right, Tom comes back and makes it right. One call. That’s the promise, and it’s on the contract, not buried in fine print.
Our crews serve Surfside locally, dispatched from our Miami office. We know the lots, the flood zones, and the county inspectors. And we’re background-checked and uniformed on every visit, because the people on your property should carry the same name as the owner who answers the phone.
Our Home Additions & ADU Services in Surfside
ADU Design & Permitting
Most of the ADUs we scope in Surfside sit on unincorporated county land, which means Miami-Dade County permits, not Town of Surfside permits. That shifts plan review timelines and inspection protocols, and it changes the drawing set. We handle the full package: site plan, structural drawings, county submittal, and resubmittal if the reviewer kicks it back. You shouldn’t be the one faxing corrections to the county.

Garage Conversion ADU
Converting an attached garage in Surfside can work, but the county cares about flood elevation and separation from the main dwelling. A garage conversion in Surfside generally lands between $30,000 and $80,000, with the wide spread driven by whether the existing slab meets code or has to be cut out and repoured. We verify that before we quote, not after you sign.

New Detached ADU
A new detached ADU in Surfside is a full ground-up build, and the site work usually costs more than people expect. Shallow groundwater means slab-on-grade moisture wicking is a real failure point. We spec a vapor barrier and drainage plan that keeps the flooring from failing after the punch list is done. On Bay Drive, we scoped a detached ADU above the flood plain and threaded the drainage plan through county public works, where the septic setback drove the foundation layout more than the lot line did. Our crew set the rough-in so the plumber could tie the waste line without a pump, and we walked the inspection sign-off before the drywall went up.

Junior ADU & Interior Conversion
A junior ADU inside an existing Surfside home can be the fastest path to extra space without a new foundation. But the county still wants to see the converted area meet egress, ventilation, and minimum ceiling requirements. We’re comfortable with that process. We pull the permit, schedule the inspections, and stand there when the inspector signs off. You’ve never pulled a permit before? That’s fine. We do it every week.

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 Surfside
When we frame and finish an addition in Surfside, we install materials you can look up, not mystery brands off a van. We carry Schluter systems in wet areas, Grohe fixtures where you want them, and GAF roofing products when the addition ties into an existing roofline. Salt air in Surfside eats cheap materials fast, so we don’t install them. If your addition has a bathroom, a kitchenette, or a new roof tie-in, we spec brands that hold up a block from the ocean.
Common Home Additions & ADU Problems We See in Surfside Homes
- Bidding before a county site survey. A well or septic easement you didn’t know about shifts the ADU location and the price moves with a change order. We survey first, then quote. An allowance that isn’t on paper is a surprise waiting for a date.
- Long material hauls on open lots. Concrete and trusses don’t deliver themselves to the back of a deep Surfside parcel. Framing allowances blow past the draw schedule when access is tight. We price haul time and equipment access up front.
- Slab-on-grade moisture wicking. Shallow groundwater just feet below the surface wicks into slabs and ruins flooring that looked perfect at final walkthrough. We detail the vapor barrier and drainage so the floor still looks right a year later.
- County inspection sequencing surprises. On county-land ADUs, the order of inspections can stall a job for weeks if you don’t stage the work in the right sequence. We schedule around the county’s rhythm, not against it.
Pricing for Home Additions & ADU in Surfside, FL
Here’s what Surfside homeowners should expect to budget for the most common scopes we build:
| Project Type | Typical Cost in Surfside |
|---|---|
| Home Addition | $45,000 - $130,000 |
| ADU Construction | $90,000 - $220,000 |
| Garage Conversion | $30,000 - $80,000 |
What moves the number on a Surfside job? Site access for material delivery, county plan review fees, septic setbacks, and whether the addition sits on open land or attaches to the existing home. We write it all down as a line-item quote before you commit. And if the scope changes, you get a written change order before a single nail moves. No surprises at the final invoice. Call (877) 610-1318 to schedule a free estimate. No trip charge inside the county.
We Also Serve Cities Near Surfside
While we’re on the ground in Surfside, our crews also cover Home Additions & ADU in Surfside neighbors including Bay Harbor Islands, North Miami, Golden Glades, and Miami Shores. If you’re in the 33181 corridor, the same crew that knows county permitting and septic setbacks can handle your addition or ADU. Same standards, same written promises.
Serving Surfside, FL - Our Local Coverage Area
We’re based in the Surfside 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 Surfside
Yes. If your Surfside lot is in unincorporated county jurisdiction, a detached ADU requires Miami-Dade County permits, and the septic system adds a layer the building department takes seriously. The septic tank and drain field have setback requirements that dictate where the ADU can sit, often more strictly than the lot line does. We get the site plan reviewed by the county health department before we finalize the foundation layout. That way we’re not moving the building after you’ve paid for drawings. Call (877) 610-1318 and we’ll check your parcel’s jurisdiction before anything gets drawn.
We price the haul as a specific line item, not buried in a general allowance. Long material hauls on Surfside open lots add cost for concrete trucks, truss deliveries, and equipment access if the ground is soft from high water table conditions. We walk the lot, measure the actual distance from the road to the build site, and put that number in writing. It’s one of the most common reasons a competitor’s quote comes in low and then grows. Ours doesn’t, because the haul is already in the scope.
Two reasons. First, Surfside sits on a barrier island with shallow groundwater, which means deeper footings and more concrete than a first-floor slab in a drier inland city. Second, lifting framing, roofing, and finish materials to a second floor on a tight coastal lot costs more in labor and equipment. The salt air also means we spec corrosion-resistant fasteners and flashings, which add cost but keep the addition from rusting inside a decade. We’ll show you exactly where those dollars go in the line-item estimate.
Yes, and you’re welcome to be as involved or as hands-off as you like. We pull the county permit under our license, schedule every inspection, meet the inspector on site, and walk the sign-off with you. Most of our Surfside customers have never pulled a permit before, and that’s normal. The inspector works for you, not for us. That’s why we like him. When the final inspection passes, you’ll have the signed card and we’ll have the job done right.
Older Surfside homes often sit on septic, not sewer, and that changes a garage conversion in two ways. The converted unit’s plumbing has to tie into the existing septic system without exceeding its capacity, or the county requires an upgrade. And the flood elevation rules on a barrier island can force you to raise the finished floor, which changes the door thresholds and the stair geometry. Newer inland cities don’t deal with any of that. We scope it, price it, and put it in writing before the first nail moves.
Talk to Tom’s Crew About Your Surfside Addition or ADU
If you’re planning a home addition or ADU in Surfside, start with a phone call. We’ll walk your lot, check your jurisdiction, and give you a written line-item estimate. Every permit pulled, every change order on paper, every job backed by the 90-Day Done Right Promise. Proudly serving local communities for over 29 years, with a permanent 10% senior and veteran discount and a free second opinion on any written estimate. Call (877) 610-1318 today.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Surfside since our founding in 1998.







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