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Quikrete Home Additions & ADU: The Miami Owner’s Guide
Quikrete home additions and ADU construction in Miami typically runs $53,100 to $153,400, and that range reflects real differences in foundation work, wind-rated framing, and finish level, not vague guesswork. We stock Quikrete products and build additions and accessory dwelling units from the slab up, with a written price before the first tool leaves the truck. Most owners call us after a previous contractor’s concrete work started spalling or cracking within the first two Miami summers, which is usually when they discover how much the original mix and curing method mattered.
This page covers what Quikrete products actually work for South Florida additions and ADUs, what fails first, what it costs to build correctly, and what we do differently so you don’t have to fix the same wall twice. Isaac Pruett has been reading Miami job sites for over a decade, and he’ll tell you the same thing he tells every homeowner in Coconut Grove, Kendall, and Hialeah: concrete is only as good as the prep under it and the cure after it.
Which Quikrete Models This Applies To
For Miami additions and ADUs, the Quikrete products that matter are their concrete mixes, masonry cements, and surface bonding materials, not a single model number. The compatibility gotcha most owners miss: Quikrete 5000 is the typical spec for load-bearing slab and stem wall pours here, while standard Quikrete Concrete Mix is not rated for the same compressive loads. If your engineer’s drawings call for 4,000 psi concrete, Quikrete 5000 works. If the plans say 3,000 psi, the standard mix is fine. Using the wrong one means a slab that won’t pass inspection or a stem wall that starts hairline-cracking before the drywall goes up.
For block walls, Quikrete Type S Mortar is the right choice in South Florida because it holds up better against wind-driven rain and salt air than Type N. For stucco and surface bonding, Quikrete Surface Bonding Cement is what we specify on ADU block work. We’re an independent service provider and not affiliated with Quikrete, but we stock their products because they behave predictably when mixed and cured correctly. When it comes to OEM versus aftermarket for concrete products, there is no realistic aftermarket equivalent, and we won’t pretend otherwise. The bag mix is the part.
Styles & brands we work with
Signs Your Quikrete Home Additions & ADU Is Failing
- Cracking that follows mortar joints within the first two years. This usually means the original contractor used Type N mortar where Type S was needed, or mixed too dry. In Miami humidity, the fix is repointing, not caulk.
- Spalling on the slab surface, especially near the edges. Water got into the concrete during the first cure or the mix was over-watered on site. Spalling never stops on its own, and every wet season makes it worse.
- Stucco pulling away from the block wall in patches. The surface bonding cement was applied to a dirty or dry block wall, which breaks the bond. Once you hear a hollow sound when you knock, that section is done.
- Water stains creeping up the interior drywall after heavy rain. This points to a failed stem wall or a missing moisture barrier at the slab edge, two things that should have been caught during the addition’s rough inspection.
- Doors and windows that start sticking in an ADU built within the last three years. That’s settlement, often because the slab was poured on uncompacted fill. In Miami, where the water table moves seasonally, compaction is not optional.
See the difference
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After
Before
After
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AfterReplacement Cost & What’s Included
For a ground-up Quikrete ADU in Miami, plan on $106,200 to $259,600 for a finished, permitted unit with a bathroom and kitchenette. A home addition, like a bedroom and bath bump-out, lands at $53,100 to $153,400. The range comes down to three things: how much site work your lot needs, whether the existing slab can be tied into, and the finish level you choose for the interior. A garage conversion using the existing slab runs $35,400 to $94,400, usually the least expensive way to add a legal ADU in Miami.
Every price we give is written and fixed before work starts. That includes demolition and haul-off, concrete and block work, framing, rough and finish electrical and plumbing, drywall, paint, and the final inspection. No change orders unless you request a change. The work is covered for 365 days from the completion date under our Done Right Promise: if something we built isn’t right within a year, we fix it at no cost to you.
DIY or Call Us?
You can safely check a few things yourself: look for cracks along mortar lines, tap stucco to find hollow spots, and watch how water pools near the slab edge after rain. That tells you whether you have a problem worth calling about. What you should not do is mix and pour structural concrete yourself, and here’s the honest reason: a bad slab or stem wall in Miami doesn’t just look bad. It fails inspection, then fails again when the next hurricane season tests it. Tearing out and repouring costs more than doing it right the first time.
If the failure is inside the wall, under the slab, or against the roofline, call us. We’ll tell you what’s actually wrong and what it costs to fix. A reader who has a Quikrete product and a failing wall needs a straight number and a date, not a lecture. Call (850) 780-8123 for that.
FAQs
A properly poured, cured, and sealed Quikrete slab and block wall in Miami will last 50 years or more, but the waterproofing and moisture barrier are the parts that typically fail first if they were skipped or installed wrong. The concrete itself is rarely the weak point. The weak point is almost always what someone did, or didn’t do, at the slab edge and around penetrations. Call (850) 780-8123 for an exact quote on your addition or ADU, estimates are free.
Minor spalling, hairline cracking, and small stucco delamination can often be repaired with repointing, patching, and re-bonding, which is far cheaper than rebuilding. If the foundation has settled or the stem wall is compromised, repair stops being a honest option. We’ll tell you which one you have before we give you a number. Call (850) 780-8123 and we’ll look at it.
Most Miami additions take 10 to 16 weeks from first inspection to final, and a full ADU takes 4 to 7 months depending on utility work and permit timing with the city. The concrete phase itself is typically one to two weeks. We give you a schedule in writing. Call (850) 780-8123 for a timeline on your specific project.
We stock the Quikrete products we build with: 5000 mix, Type S mortar, and Surface Bonding Cement, so there’s no ordering delay. If your project calls for something unusual, we source it before your job starts and the price is locked in when we quote it. Call (850) 780-8123 and ask for Isaac directly.
Tell me what you need done. I’ll tell you what it costs and when it’s finished, and I’ll mean both.
Written by Isaac Pruett, Owner, Mason Remodeling Co Miami at Mason Remodeling Co Miami, serving Miami and nearby areas.
