Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Fast, Reliable Home Additions & ADU Across Riviera Beach
A home addition or ADU in Riviera Beach runs $45,000 to $130,000 for a second-story addition, and $90,000 to $220,000 for a new detached ADU, with garage conversions landing between $30,000 and $80,000. The single biggest cost variable in this city is flood elevation: once a project exceeds 50% of the structure’s assessed value, FEMA rules require the entire building to be raised to current Base Flood Elevation. That one trigger changes everything about scope and budget, and most homeowners don’t learn about it until the permit review. We’ve built, framed, and permitted enough additions and ADUs in Riviera Beach to know exactly where the code will push back, and we plan for it before the first nail moves. Call (877) 610-1318 and Tom or one of his sons will walk you through what your specific property will actually require.
Why Barrett & Sons Construction Is Riviera Beach’s Preferred Home Additions & ADU Company
Barrett & Sons Construction has been owner-operated since 1998, and the crews you’ll see on your Riviera Beach job are led by Tom Barrett and his sons. Not a franchise dispatching strangers from a call center. Tom’s name, address, and license number are published and verifiable, and if something isn’t done right, he comes back. That’s the 90-Day Done Right Promise, written on every contract, and it’s been our standard in Riviera Beach for a long time.
Riviera Beach homeowners tell us the same story over and over: a national outfit quoted one price on the phone, then handed them a higher bill at the door. We don’t work that way. Every scope, every allowance, every price change arrives as a written change order before work happens. The allowance that isn’t on paper is a surprise waiting for a date. Our Home Additions & ADU team specs the full permit path before you sign anything, so you’re not discovering FEMA rules halfway through the demo.
We answer our own phone, 24/7, with a live person. When you call about an addition on a canal-side street off Blue Heron Boulevard, you’re talking to someone who knows exactly why that address matters for flood zone code. That’s the difference between a contractor who works in Riviera Beach and one who happens to be passing through.
Our Home Additions & ADU Services in Riviera Beach
New Detached ADU
A new detached ADU in Riviera Beach gives you separate rental income or a place for family without sharing walls, but it also triggers the full weight of local code: FEMA AE or VE flood zone foundation requirements, Coastal Construction Control Line setback rules on Singer Island, and wind-load ratings that inland contractors never think about. We design the ADU to your specific lot from day one. If your parcel sits on a canal off Blue Heron Boulevard, we plan for elevated foundation work before you spend a dollar on framing. New detached ADUs in Riviera Beach run $90,000 to $220,000, and the range depends heavily on your flood zone and site access. Every permit gets pulled, and every inspection gets signed.

Garage Conversion ADU
Converting an attached or detached garage is usually the fastest way to add living space in Riviera Beach’s older mainland neighborhoods like Broadway and Old Riviera, where mid-century CBS homes have generous lot sizes but limited interior square footage. The catch: those pre-1994 garages were built before modern wind-load codes existed. We see garage conversions where the existing roof assembly won’t pass current Palm Beach County wind uplift standards, which means replacing the entire lid, not just strapping it. A garage conversion ADU in Riviera Beach runs $30,000 to $80,000. We’ll give you a written line-item scope before work starts so the FEMA 50% substantial improvement threshold doesn’t blindside you.

Second Story Additions
Going up instead of out is the right move on many Riviera Beach lots, especially on the mainland where setbacks leave little side yard to work with. A second-story addition runs $45,000 to $130,000 in this market. The code demands coastal 170 mph Miami-Dade rated wind assemblies here, not the inland standard, which is why our Riviera Beach Roofing specs always start with code-compliant assemblies. We spec hot-dipped galvanized strapping and LED anchor bolts at every load-bearing connection, because the Atlantic salt air in Riviera Beach will chew through standard fasteners in under two years. The inspector will check, and you’ll want him to. The permit inspector works for you, not for me.

Junior ADU & Interior Conversion
A junior ADU or interior conversion lets you add a compact living unit inside the existing footprint of your Riviera Beach home, usually with its own bath and kitchenette. This approach often makes the most sense when the FEMA substantial improvement threshold would push a larger addition over the 50% line. Because you’re working within existing walls, the trigger is less likely to fire. We handle the egress windows, fire separation, and Windows & Doors - Riviera Beach code requirements for separate entrances, and we pull every permit. Junior ADU and interior conversion pricing follows the same honest, written change order process as our larger jobs.

What happens when you call
- 1
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 Riviera Beach
We build with materials you can look up and verify, because the last contractor most Riviera Beach homeowners used put mystery brands off a van in the driveway. On hardscape and site prep around ADUs and additions, we install Techo-Bloc and Belgard pavers. On structural and weatherproofing components, we specify hot-dipped galvanized and stainless hardware rated for coastal salt-air exposure. We stock common Riviera Beach-specific components, so you’re not waiting weeks on a part while your permit clock runs. If a product won’t pass Riviera Beach’s coastal wind-load and corrosion requirements, we won’t put it on your property.
Common Home Additions & ADU Problems We See in Riviera Beach Homes
- FEMA substantial improvement triggers mid-project: A homeowner signs a contract without a flood-zone scope of work, then the city flags the addition at 50% of assessed value. The entire building must be raised to Base Flood Elevation, and the project dies or doubles in cost. We pull the FEMA review before framing starts on every Home Additions & ADU in Riviera Beach job.
- Salt-air corrosion on the wrong hardware: A contractor uses standard galvanized connectors on an ADU near the Intracoastal. Within two years, the fasteners are corroded to the point the inspector won’t sign the final. We spec hot-dipped galvanized or stainless on every exposed or embedded component, every time.
- Coastal wind uplift failures on pre-1994 flat roofs: Many 1950s and 1960s CBS homes in Riviera Beach still carry original flat or low-slope roofs that fail current Palm Beach County wind uplift standards. Any addition that ties into that roof must bring the entire assembly up to code. That’s a full replacement, not a patch job.
- Garage conversion roofs that don’t meet coastal rating: We’ve seen garage conversions framed with roofs that only meet inland wind uplift, not the 170 mph Miami-Dade rating Riviera Beach requires. The permit gets revoked and the entire roof assembly has to be redone. We write the wind-load rating into your contract from the first line item.
Pricing for Home Additions & ADU in Riviera Beach, FL
Here’s what you’ll actually pay in Riviera Beach, and we’re giving you the numbers before you call. A new detached ADU runs $90,000 to $220,000. A second-story addition runs $45,000 to $130,000. A garage conversion ADU runs $30,000 to $80,000. A junior ADU or interior conversion typically falls under the addition range depending on square footage and whether you’re adding a bath. What moves the number in Riviera Beach: your FEMA flood zone, whether your lot is mainland or Singer Island, how much of the existing structure ties into the new work, and whether the project crosses the 50% substantial improvement threshold. Every quote comes as a written, line-item scope with allowances spelled out in writing. You’ll never get a surprise invoice from us, because the allowance that isn’t on paper is a surprise waiting for a date.
| Project Type | Price Range in Riviera Beach |
|---|---|
| New Detached ADU | $90,000 - $220,000 |
| Second Story Addition | $45,000 - $130,000 |
| Garage Conversion ADU | $30,000 - $80,000 |
Call (877) 610-1318 for a free estimate. We’ll walk your specific Riviera Beach property and give you a written number you can hold us to.
We Also Serve Cities Near Riviera Beach
If you’re in Lake Park, North Palm Beach, Palm Beach, or West Gate, our crews serve your area too. We know these communities and the flood and wind zones that govern them. When you call about an addition or ADU anywhere near the Intracoastal, you’ll get the same written change order process and 90-Day Done Right Promise we give our Riviera Beach customers. Riviera Beach is home base for this page, but the standards don’t change across the bridge.
Serving Riviera Beach, FL - Our Local Coverage Area
We’re based in the Riviera 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 Riviera Beach
A new ADU in a Riviera Beach VE flood zone requires an elevated foundation with the finished floor at or above Base Flood Elevation, typically on piers, columns, or fill that meets FEMA and Coastal Construction Control Line setback rules. We pull the elevation certificate and design the foundation to code before you spend a dollar on framing. Call (877) 610-1318 for an exact quote on your specific parcel. Estimates are free.
It can, and that’s the moment most projects on canal-side streets off Blue Heron Boulevard go sideways. If the conversion cost exceeds 50% of the structure’s assessed value, FEMA requires the entire building to be raised to current Base Flood Elevation. We run the number before you sign, so you know if your garage conversion is safe or if you need to scale back or go a different route. Call (877) 610-1318 and we’ll check your specific property.
Your Riviera Beach second-story addition must meet the coastal 170 mph Miami-Dade wind-load rating, not the inland standard. That means hot-dipped galvanized strapping, LED anchor bolts at every load-bearing connection, and roof assemblies tested and rated for coastal uplift. We spec those products from the first line item, and we pull a revision permit if you change the scope mid-rough-in, the way we did on a Broadway neighborhood CBS home when the owner added a Cambria quartz island after framing. That’s what a compliant quote includes.
Documented wind mitigation on a Riviera Beach ADU can lower your windstorm premium, because insurers credit the rated roof assembly, strapping, and anchor system we build and the inspector signs off on. We frame the addition on a 1960s Broadway neighborhood CBS home where the original flat roof had failed wind uplift, and the homeowner told us their insurer acknowledged the new wind-rated envelope. You should ask your agent for specifics, but the documentation we hand you at close-out is what makes the case.
Because the Atlantic salt air in Riviera Beach corrodes standard galvanized hardware faster than inland contractors expect, and the inspector will refuse the final sign-off when the fasteners have rusted through. We’ve seen it happen on ADUs near the Intracoastal within two years. We write corrosion-resistant hardware into your original scope, so there’s no change order later. If a change order ever does come, it arrives in writing before the work happens.
Call Barrett & Sons Construction for Your Riviera Beach Home Addition or ADU
You need a contractor who knows FEMA rules, coastal wind-load ratings, and what Riviera Beach’s 1950s and 1960s CBS homes actually take to bring up to code, including Bathroom Remodeling in Riviera Beach that meets flood elevation and wind-load standards. That’s us. Call (877) 610-1318 for a free estimate, and you’ll talk to a live person who knows this city. Tom Barrett and his sons run the crews, the permits get pulled, the inspections get signed, and every price change arrives in writing before a single nail moves. That’s the 90-Day Done Right Promise, and it’s been our standard for over 29 years.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Riviera Beach and the surrounding communities since 1998.







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