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 Hialeah
A permitted home addition or ADU in Hialeah typically runs $45,000-$130,000 for a room addition and $90,000-$220,000 for a new detached ADU, with most projects taking 4-9 months from permit to final inspection. If you live in the 33012 or 33015 ZIP and you’re wondering whether your 1950s CBS house can handle a second story or a garage conversion, the short answer is yes, if you plan the permit path correctly. We’re Barrett & Sons Construction, owned by Tom Barrett, and we’ve been building residential additions and ADUs in South Florida since 1998. Call (877) 610-1318 and we’ll walk your property with you, pull the Hialeah permit history, and give you a written line-item estimate before any work starts.
Why Barrett & Sons Construction Is Hialeah’s Preferred Home Additions & ADU Company
Hialeah isn’t like the rest of Miami-Dade. It has its own building department, its own inspection cadence, and its own way of handling the decades of unpermitted work sitting in pre-Andrew CBS homes. Contractors who don’t work here regularly get surprised by that. We don’t, because our Home Additions & ADU team has been through the Hialeah permit office enough times to know exactly when to file, what to bring, and which questions to ask before you spend a dollar on drawings.
Tom Barrett’s name, address, and license number are published and verifiable, and he stands behind every job with the 90-Day Done Right Promise. It’s written on every contract: if something’s not done right, one call brings Tom back. Our crew members are background-checked and wear the Barrett & Sons name on their shirts. We answer the phone live, 24/7. And every price change, every allowance, every scope adjustment arrives as a written change order before a single nail moves.
Hialeah homeowners between 50 and 70 know what a surprise invoice looks like. That’s exactly who we built this company for. Ask anyone on your street, or look up the license number yourself.
Our Home Additions & ADU Services in Hialeah
ADU Design & Permitting
Before we touch a wall, we run the Hialeah permit history on your property. That means searching for open permits from prior owners, a step that’s routine here and almost unheard of in unincorporated Miami-Dade or Hialeah Gardens. If a 1987 carport enclosure was never finaled, Hialeah won’t close your new ADU permit until that old one is resolved or legally abandoned. We handle that paperwork, coordinate the survey, and get the stamped drawings through Hialeah’s plan review. Call (877) 610-1318 to start with a free permit history check.
Garage Conversion ADU
Converting a garage into a living unit in Hialeah usually runs $30,000-$80,000, and the biggest cost driver isn’t drywall, it’s bringing the old structure up to current code. Most garages on 1950s-1970s CBS homes were never designed as conditioned living space. We typically need to upgrade the slab insulation, reframe the garage door opening for impact-rated windows and doors with Miami-Dade NOA approval, and run a new subpanel because the original 100-amp service can’t carry a kitchenette and mini-split. The finished unit needs its own address and its own electrical meter if it’s a true detached ADU.
New Detached ADU
A detached ADU in Hialeah starts around $90,000 and can reach $220,000 depending on size, finishes, and how much site work the lot needs. Hialeah sits on low-lying Miami limestone with a water table that can rise within two feet of grade during the June-October wet season. Any footer excavation for a new detached structure means dewatering. We plan for that from day one, not when the excavator hits water. The building also has to meet HVHZ wind-load requirements, which changes the roof-to-wall connection details and the sheathing schedule.
Junior ADU & Interior Conversion
A junior ADU, usually 500 square feet or less built inside the footprint of the existing home, is the least expensive path to a legal rental unit or in-law suite. In Hialeah that often means converting a den, a utility room, or an enclosed patio into a permitted living space with its own entry, kitchenette, and bath. The catch is that many of those existing spaces were added without permits over the years, and Hialeah’s inspectors will require documentation of the original construction before they’ll sign off on the conversion. We map out that process before you commit.
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 Hialeah
Every window, door, and roof component we install on a Hialeah addition or ADU has to carry Miami-Dade Notice of Acceptance approval. We install products from PGT, CGI, and Simonton, brands that publish their NOA numbers and hold up under Hialeah’s HVHZ wind codes. If a quote leaves the NOA documentation out, the inspector will catch it at rough-in and you’ll be tearing out brand-new windows. We don’t put you in that position. Our suppliers stock these brands locally, so lead times stay short and warranty service doesn’t require a trip across the state.
Common Home Additions & ADU Problems We See in Hialeah Homes
- Open permits from prior owners. Hialeah’s permit office sees so many pre-Andrew CBS homes with layered unpermitted additions that inspectors routinely flag old permits that were never finaled. A title search won’t always catch these, and they can freeze a framing inspection two weeks in.
- Non-NOA windows and doors specified to save money. Hialeah requires Miami-Dade NOA-approved products for every impact-rated opening. We’ve seen crews install products that were impact-rated in Broward but not NOA-listed for Miami-Dade, and the inspector fails the rough-in.
- Undersized footer excavation hitting the water table. On lots near the Miami Canal or in the 33012 ZIP, the water table sits close to grade. A footer dug without dewatering turns into a three-day pumping job before concrete can be poured.
- Unpermitted framing discovered inside walls. Opening a wall for a second-story addition on a 1950s CBS home often reveals aluminum Florida rooms, abandoned knob-and-tube splices, and footings that were never inspected. All of that has to be disclosed and remediated before the new permit closes.
Pricing for Home Additions & ADU in Hialeah, FL
A home addition in Hialeah runs $45,000-$130,000. A detached ADU runs $90,000-$220,000. A garage conversion falls between $30,000 and $80,000. If you’re adding impact windows and doors as part of the scope, budget $8,000-$25,000 for that line item. These numbers reflect Hialeah’s permit fees, HVHZ engineering requirements, and the reality of building on low-lying limestone. The single biggest variable is how much unpermitted work exists in the existing structure, because bringing that to code is mandatory before the new square footage can pass inspection. We give you a written line-item estimate, and every change after that arrives as a written change order. Call (877) 610-1318 to schedule your free estimate in Hialeah.
| Project Type | Typical Hialeah Range |
|---|---|
| Home Addition | $45,000 - $130,000 |
| ADU Construction | $90,000 - $220,000 |
| Garage Conversion | $30,000 - $80,000 |
| Impact Window Installation | $8,000 - $25,000 |
We Also Serve Cities Near Hialeah
In addition to our work across Home Additions & ADU in Hialeah, we regularly serve Hialeah Gardens, Miami Lakes, Miami Springs, and Opa-locka. If your property sits just outside Hialeah’s city limits, the same permitting team handles your job. Call (877) 610-1318 and we’ll confirm coverage and schedule a walkthrough.
Serving Hialeah, FL - Our Local Coverage Area
We’re based in the Hialeah 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 Hialeah
Yes. Hialeah requires a separate building permit for every new ADU, regardless of when the main house was built. The original home’s age doesn’t exempt the new structure from current HVHZ wind-load codes, Miami-Dade NOA product requirements, or Hialeah’s own inspection process. We handle the full permit set, from site survey to final inspection. Call (877) 610-1318 for a free permit history check on your property.
An open permit from a prior owner can add two to six weeks to your ADU timeline. Hialeah’s building department will not close a new permit until the old one is resolved or legally abandoned, which often means finding the original contractor or proving the work was done to code. We run this search before we submit drawings so you aren’t surprised mid-framing. Call (877) 610-1318 and we’ll check your address this week.
Every opening in a Hialeah home addition must use products that carry a current Miami-Dade Notice of Acceptance for High Velocity Hurricane Zone use. That includes windows, exterior doors, and garage doors. The NOA number has to be documented in the permit package. We install PGT, CGI, and Simonton products with current NOAs and keep the documentation on file for your insurance records. Call (877) 610-1318 for a written line-item quote.
Yes, if the original construction can be documented or brought to current code. Hialeah’s inspectors will require proof that the slab, framing, and electrical meet today’s standards, and many older aluminum rooms don’t. We assess the existing structure, determine what’s salvageable, and give you a straight answer on whether conversion or rebuild makes more sense. Call (877) 610-1318 to schedule a walkthrough.
Documented HVHZ wind-load compliance, including Miami-Dade NOA product records and structural engineering letters, gives your insurance carrier the specific documentation they need to apply wind-mitigation credits. It’s not a guarantee of a lower premium, but it removes the “unknown construction” penalty that insurers apply when they cannot verify how the structure was built. We provide all documentation at closeout. Call (877) 610-1318 for more detail.
If you’re planning a home addition or ADU in Hialeah, call Barrett & Sons Construction at (877) 610-1318. Tom Barrett will walk your property himself, review the permit history, and give you a written estimate with every allowance on paper. The free estimate is the first step.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Hialeah and South Florida since 1998.