The Florida Keys are tough on construction materials: saltwater eats away at steel, storm surges weaken foundations, and heat can affect concrete before it sets. Much of this damage starts below the surface, in the aggregate: the sand, gravel, and crushed stone that make up the foundation of almost everything built.
If you choose the right aggregate, your structure will last. If you pick the wrong one, the rough Florida environment will wear it down over time.
Monroe Concrete offers a full range of coarse and fine aggregate, ready for delivery anywhere from Key Largo to Key West. In this guide, we’ll explain what aggregate is, the differences between coarse and fine materials, and how to choose the best option for your project.
Aggregate is a general term for granular materials like sand, gravel, or crushed stone that are used as a base, filler, or structural component.
Florida ranks third in the country for crushed stone production, according to the United States Geological Survey. It’s one of the most-used raw materials in the construction industry.
Aggregate serves a range of functions on a construction site. It’s the primary ingredient in concrete mixes, a compacted base layer under driveways and roads, and a drainage medium around pipes and foundations. Choosing the right material depends entirely on the application, which is why aggregate falls into two main categories: coarse and fine.
The primary difference between coarse and fine aggregate is particle size. Coarse aggregate has particles larger than 4.75 mm (about 3/16 inch), while fine aggregate, which is mainly sand, has smaller particles.
Both types are sorted by size, using standard aggregate grades that show the particle-size range. The right grade depends on your project. For example, drainage layers need a different size than concrete mixes.
Wondering what size gravel to use for concrete? Most mixes use #57 stone, which ranges from 3/4 inch to 1.5 inches, as the standard coarse aggregate. For smoother finishes or finer work, #89 stone, which is 3/8 inch or smaller, is often used. Monroe Concrete offers both, plus a full range of sand and fill materials for any project.
Monroe Concrete delivers coarse and fine aggregate stone, fill, screenings, and recycled materials anywhere in the Florida Keys.
You can see our full inventory on the Materials page.
Aggregate makes up 60 to 75% of concrete’s total volume. It helps reduce shrinkage, which is important because shrinkage causes cracks. In a saltwater environment, corrosion often starts when concrete cracks.
For most concrete pours, #57 stone is the standard coarse aggregate. If you need a smoother surface or a finer mix, we recommend choosing #89. Monroe Concrete’s ready-mix already includes the right aggregate for your application, so if you order ready-mix, you don’t need to worry about selecting the aggregate.
Selecting the right aggregate also affects how long a structure lasts. In the Florida Keys, saltwater speeds up corrosion, so for bridge repairs, reinforced slabs, and any structural pour near water, aggregate selection and the right admixtures help keep that process in check.
In most places, picking the right aggregate materials depends on how you’ll use it and what size you need. In the Florida Keys, the environment matters just as much, and it often determines how long your structure will last.
Start by asking yourself these questions:
If you need help estimating volume, Monroe Concrete’s concrete calculator can help. Questions about which product fits your project? Contact our team, and we’ll help you figure it out.
Getting aggregate delivered in the Florida Keys is different from anywhere else. With the Overseas Highway (U.S. 1) as the only road in and out, working with a supplier who doesn’t know the area can waste valuable time.
Monroe Concrete keeps aggregate in stock and delivers from Key Largo to Key West. We understand the challenges of tight schedules and which materials last in this climate. When you order from us, your aggregates and mixes come from a local supplier who knows what works in the Keys and what doesn’t.
We supply aggregate for all types of Keys projects: driveways, foundations, road base, seawall repair, and coastal erosion control. If you’re not sure what you need or how much, contact us and we’ll work through it with you.
Gravel is a type of aggregate, but the two words don’t mean the same thing. Aggregate is a broader term that includes sand, crushed stone, recycled concrete, limestone, and other granular materials, as well as gravel. When a spec sheet asks for aggregate, it means a certain type and grade of material, not just any loose stone.
Aggregate is used in almost every part of construction. As a base layer under driveways, roads, and foundations, it spreads out weight and helps with drainage. Around pipes and buildings, it helps move water away. For erosion control, materials like limestone boulders and stone keep soil and structures in place against water and waves. Landscaping, pipe bedding, backfill, and road base all need the right type of aggregate.
The amount you need depends on your project’s size and how deep the material should be. Monroe Concrete has a concrete calculator to help you figure out how much material you need based on your measurements. If your project has special base or drainage needs, call us, and we can help you with the numbers.
FDOT-approved aggregate meets the Florida Department of Transportation’s standards for materials used in state-funded projects. Monroe Concrete’s crushed concrete fill is FDOT-approved and can be used as a subbase instead of regular gravel. The FDOT Aggregate Acceptance Unit keeps the list of approved sources and material standards for Florida’s transportation system.