Fast, Reliable Home Additions & ADU Across Palm Beach
Home additions and ADU construction in Palm Beach typically run $45,000-$130,000 for room additions and $90,000-$220,000 for detached ADUs, with ARCOM approval adding a structured review layer unique to this barrier island. We’re Groundwork Construction Co. of South Florida, and our crews make the run from Fort Lauderdale to Palm Beach regularly - usually within 45 minutes to an hour depending on bridge traffic. If you’re adding square footage to a Mizner-era estate or converting existing space into a junior ADU, you need a contractor who knows ARCOM’s monthly calendar, understands cast-stone matching, and specs marine-grade hardware that won’t corrode in six months. Call (844) 665-0162 for a free estimate.
Why Groundwork Construction Co. of South Florida Is Palm Beach’s Preferred Home Additions & ADU Company
We’ve learned Palm Beach’s rhythms. The Town’s Architectural Commission meets on a fixed schedule, and we’ve built our project timelines around that reality. Our clients on the island - from North End estates near the Palm Beach Country Club to properties along South Ocean Boulevard - don’t wait extra months because we missed a submittal deadline.
Raymond Estevez, who leads our company, insists that every Palm Beach project start with a full ARCOM pre-consultation. That single step has saved our clients from the 30-day delays that out-of-town contractors routinely inflict on themselves.
Our response time to Palm Beach averages under an hour for initial consultations, and we keep marine-grade fasteners and impact-rated window samples in stock specifically for coastal exposure zones like yours. When you’re matching 1920s Mediterranean Revival detailing or engineering a new slab to post-2002 wind codes, that preparation matters.
We don’t subcontract your project into fragments. Our Home Additions & ADU team handles design coordination, ARCOM documentation, structural engineering, and final finish work - one contractor, every phase.
Our Home Additions & ADU Services in Palm Beach
Junior ADU & Interior Conversion
Palm Beach’s Mizner-era estates are full of underused spaces - carriage houses, staff quarters, pump houses - that convert beautifully to junior ADUs. On a 1930s Mediterranean Revival estate near the Intracoastal, our crew converted an old pump house into a junior ADU. The original clay barrel-tile roof had to be matched and the concrete slab re-poured to meet post-2002 wind codes, all while coordinating with ARCOM’s monthly deadline. We sourced a salvaged cast-stone window surround from a local supplier to keep the historic look, and the project cleared approval in one cycle. Interior conversions in Palm Beach’s landmark-designated properties trigger ARCOM review for any exterior alteration, including new windows or doors, so we build that timeline into every proposal.
New Detached ADU
Detached ADUs in Palm Beach face a dual challenge: the Town’s strict design standards and the island’s punishing salt-air environment. We spec impact-rated windows from Andersen or PGT, marine-grade stainless fasteners, and engineered roof assemblies that meet Florida Building Code wind-speed requirements for this coastal exposure zone. For clients who want faster timelines, we partner with prefab innovators including Mighty Buildings and Boxabl - though even prefab units must pass ARCOM’s elevation and material-sample review. We handle that coordination.
Room Additions
Adding a master suite, great room, or guest wing to a Palm Beach estate means matching existing massing, roof pitch, and fenestration patterns. The island’s 1920s-1940s housing stock with its poured concrete slabs and CBS walls often requires specialty underpinning or vapor-barrier remediation that standard addition estimates miss. We identify these conditions during our initial structural assessment, not after demolition starts. Our material library includes cast-stone suppliers, pecky-cypress millwork shops, and clay barrel-tile sources that keep additions visually continuous with original construction.
ADU Design & Permitting
ARCOM’s monthly review cycle means even a one-day-late submittal for an ADU or addition can stall a project by 30 days - a scheduling reality that compounds with the island’s 1920s-1940s Mizner-era estates, where foundation work often requires matching original cast-stone and pecky-cypress details. We prepare fully rendered elevation drawings with material samples before the first submittal, and we track ARCOM’s calendar obsessively. Our permitting package includes structural engineering for post-2002 wind codes, which the Town’s building department enforces rigorously.
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 Palm Beach
We work with 50+ recognized industry brands across every project category, and you choose the brand, we handle the build. For Palm Beach ADUs and additions, that means impact-rated windows from Andersen, Pella, Marvin, or PGT; engineered roofing from GAF, CertainTeed, or Owens Corning; and cabinetry from KraftMaid or Wellborn for interior finishes. On the prefab side, we partner with Mighty Buildings, Boxabl, and Plant Prefab for clients who want modern, fast-track options. We stock marine-grade fasteners and hardware locally - standard steel corrodes within a year here, and we don’t spec it.
Common Home Additions & ADU Problems We See in Palm Beach Homes
- ARCOM submittal failures: Out-of-town contractors often miss the monthly deadline for material samples and rendered elevations, adding 30 days of delay. We build our schedules around ARCOM’s fixed calendar and pre-submit for feedback.
- Salt-air corrosion in new framing: Standard steel fasteners and aluminum framing corrode rapidly in Palm Beach’s dual-exposure salt air. We spec marine-grade stainless and impact-rated assemblies that withstand Atlantic and Intracoastal exposure.
- Foundation surprises in Mizner-era slabs: Poured concrete slabs from the 1920s-1940s often lack proper rebar or vapor barriers, requiring specialty underpinning before addition loads can be applied. We assess this before pricing, not after breaking ground.
- Historic-preservation mismatches: New construction that ignores cast-stone detailing, clay barrel-tile profiles, or pecky-cypress ceiling treatments gets rejected by ARCOM. We maintain relationships with specialist subcontractors who replicate these elements authentically.
Pricing for Home Additions & ADU in Palm Beach, FL
Here’s what homeowners in Palm Beach actually pay:
| Service | Typical Range in Palm Beach |
|---|---|
| Home Addition | $45,000-$130,000 |
| ADU Construction | $90,000-$220,000 |
| Garage Conversion | $30,000-$80,000 |
ARCOM review cycles, specialty material sourcing, and marine-grade hardware add cost compared to inland markets. Foundation remediation in older Mizner-era estates can push projects toward the higher end. We provide line-item estimates after our initial structural assessment - no lump-sum guessing. Call (844) 665-0162 for a free estimate.
We Also Serve Cities Near Palm Beach
Our crews work throughout the coastal corridor. Home Additions & ADU in Palm Beach is our specialty, and we also serve West Gate, West Palm Beach, Riviera Beach, and Lake Park - though ARCOM’s review requirements apply only within the Town of Palm Beach itself.
Serving Palm Beach, FL - Our Local Coverage Area
We’re based in the Palm 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 Palm Beach
Yes, virtually all exterior alterations in the Town of Palm Beach require ARCOM approval before permitting, including junior ADU conversions that add windows, doors, or change rooflines. Even interior-only work may trigger review if it affects the exterior envelope. We prepare fully rendered elevations with material samples and submit on ARCOM’s monthly cycle to avoid delays. Call (844) 665-0162 to discuss your specific project.
Salt air from both the Atlantic and Intracoastal accelerates corrosion of standard steel fasteners, rebar, and aluminum framing by 3-4 times compared to inland South Florida. We spec marine-grade stainless fasteners, impact-rated windows and doors, and protective coatings on all exposed metal. Skipping this step means premature failure within 12-18 months. Call (844) 665-0162 for material specifications on your project.
Yes, and ARCOM effectively requires it on landmark-designated or contributing properties. We source matching clay barrel tile, cast-stone surrounds, and pecky-cypress millwork from specialist suppliers. Our field vignette near the Intracoastal proved this approach works - the salvaged cast-stone window surround we found kept the historic look intact and cleared ARCOM in one review cycle. Call (844) 665-0162 to review material options.
From contract to certificate of occupancy, expect 8-14 months depending on ARCOM scheduling and foundation conditions. ARCOM review alone adds 1-3 months compared to unincorporated Palm Beach County. Prefab options from Mighty Buildings or Boxabl can compress construction duration by 30-50%, but they still pass through the same ARCOM and building department reviews. Call (844) 665-0162 for a timeline specific to your property.
Yes. Mizner-era slabs from the 1920s-1940s often lack modern rebar spacing, vapor barriers, or adequate depth for today’s load requirements. We’ve seen underpinning costs add $15,000-$40,000 to projects where this wasn’t identified early. Our initial assessment includes ground-penetrating radar or core sampling when we suspect these conditions. Call (844) 665-0162 to schedule a foundation evaluation.
Ready to expand your Palm Beach home? Call Groundwork Construction Co. of South Florida at (844) 665-0162 for a free estimate. We’ll review your property, assess ARCOM requirements, and deliver a line-item proposal with real brand options - built to spec, not to convenience.
Written by Raymond Estevez, Owner at Groundwork Construction Co. of South Florida, serving Palm Beach and South Florida homeowners.