If you ask most homeowners what makes a concrete project successful or not, they’ll tell you about the mix, the finish, perhaps the contractor’s reputation. Very rarely, anyone talks about what happens before the pouring of the concrete. That is what really decides on whether a driveway, patio, foundation or slab will last for twenty years or whether it will begin to fail within the first two.
The preparation work of a site is invisible once the job is done. That’s why it’s easy to overlook and rush through without the homeowner noticing, as it’s completely covered by the concrete. However, the ground under a concrete slab continues to function after the concrete has cured. It moves, shifts, settles and reacts to moisture all year round and when the preparation below is not carried out correctly all of that movement is transferred directly to the surface above.
Planit Dirt Excavation and Concrete has been performing these services in Jacksonville, Bryant, Little Rock, Sherwood, Conway and the surrounding central Arkansas area for more than 37 years. The jobs that hold up longest are consistently the ones where the ground was prepared properly before a single yard of concrete was ordered.
What Site Preparation Actually Involves
Site prep isn’t one step. It’s a sequence of steps that work together to create a stable, consistent base for whatever concrete surface is going on top.
Clearing and grading: If there is vegetation, roots, or any organic matter in the area prior to any excavation, it must be removed. Over time, decomposition of organic matter under a slab may lead to voids that cause settling and cracking. The ground is then levelled, creating an appropriate drainage slope. A concrete surface that does not discharge water away from the adjacent structure creates issues with the slab at the same time as it draws moisture to the foundation, and eventually causes failure of the subbase material.
Correct depth of excavation: Depth of excavation will vary depending on the type of concrete being poured and soil conditions at that particular location. The depth for a residential driveway is different than a patio, a garage slab, or a building foundation, and the depth requirement is based on a variety of factors related to load, drainage and the function of the subbase. When excavating too shallow or failing to consider soft spots, it creates issues that will manifest as cracking and settling later on.
Soil assessment and stabilization: That is where experience plays a key role. Not every type of soil acts the same, and in central Arkansas, clay-heavy soil is very prevalent in Jacksonville, Cabot, Maumelle, and other nearby areas. When clay is saturated, it swells and when it is dry, it shrinks and exerts pressure on a rigid structure placed on top of it. If the soil is too soft or unstable to bear the load, it should be rectified before the base layer is laid. This can be as simple as taking out and replacing contaminated soil, compacting existing soil to a desired density or adding more soil to create a more stable platform.
The Role of the Aggregate Base
Once the subgrade is properly prepared, a compacted aggregate base layer goes down before the concrete. This layer does several things simultaneously that the concrete itself cannot do on its own.
It spreads out the load imposed on the surface above it, across the subgrade below it. It drains moisture that infiltrates the concrete from beneath or from the ground, minimizing the possibility of water being trapped in the subbase that would be damaging during freeze-thaw conditions. It provides a flat, even surface for the concrete forms and the concrete pour.
The thickness of this base layer varies based on the application and the soil conditions. A slab that’s going to carry vehicle loads needs a more substantial base than a residential walkway. A site with problematic clay soil may require a thicker base than a site with naturally stable, well-draining soil.
Compaction is the step that makes the base layer actually work. An aggregate base that’s been placed but not properly compacted will continue to settle after the concrete goes down, and the concrete will settle with it. Compaction isn’t something that can be adequately done by hand or assumed to happen on its own over time. It requires proper equipment operated by someone who knows what adequate compaction density actually looks and feels like.
Drainage: Getting Water Away From the Slab
Water is the element that does the most damage to concrete over time, not always from above but from below and from the sides. A site prepared without proper drainage planning sends water toward the concrete rather than away from it, and that water finds its way in.
Proper drainage is more than that the surface grade is correct; that is part of it. It also considers where water is coming from during heavy rain events in central Arkansas, the natural flow of water on the site, and whether the grading around the new concrete directs water away from the structure and surrounding landscape.
On larger projects like foundations and commercial concrete, drainage planning includes considering subsurface water movement and whether any drainage infrastructure needs to be installed before the base goes down. On residential driveways and patios across Benton, Alexander, and North Little Rock, it’s often simpler than that, but it still requires deliberate attention rather than assumption.
Why Arkansas Clay Makes This More Complicated
Central Arkansas clay soil isn’t a minor variable in concrete work. It’s the defining site condition that shapes every preparation decision on most projects in this region.
Clay holds water. When it’s wet, it’s soft and expansive. When it dries out, it contracts and pulls away from anything sitting above it. That cycle, which runs through every Arkansas season to varying degrees, puts constant stress on concrete that wasn’t installed over a properly prepared and stabilized subbase.
The driveways and slabs that crack prematurely in Jacksonville, Conway, Sherwood, and surrounding areas almost always have the same story underneath them. The clay subgrade wasn’t adequately addressed before the concrete went down. Either the depth of excavation wasn’t sufficient, the base layer was too thin, the compaction wasn’t adequate, or some combination of all three. The concrete itself was fine. What it was sitting on wasn’t.
Planit Dirt’s site assessment process before any project starts exists specifically to address this. What the soil looks like on the surface in central Arkansas is not always a reliable indicator of how it will behave under load and through the seasonal moisture cycles this region produces every year.
How This Connects to Specific Project Types
Driveways. A driveway that carries vehicle loads needs a stable, well-drained subbase to perform across years of use. Driveways that crack within a few years of installation almost always have inadequate base preparation as the root cause, not the concrete mix or the weather.
Patios and pool decking: Poor drainage of patios or insufficient compaction of surface layers, or organic material left in the subgrade, can be the cause of uneven surfaces or settling.
Foundations: The most important use of site prep is when it comes to the foundations themselves, as the results of a failed application can affect all of the foundation’s supporting structures. The load distribution, soil stabilization and drainage must all be right before a foundation pour.
Concrete slabs for garages and outbuildings: A slab designed to support loads from vehicles or equipment, or as a permanent working surface should be designed to meet the heavier demands and not the standards set for residential walkways.
Planning a Concrete Project? Start Here
Every Planit Dirt project starts with a site visit and an honest assessment of what the ground actually requires before concrete is specified. No upfront payment required, and free estimates are available across Jacksonville, Little Rock, Bryant, North Little Rock, Sherwood, Conway, Benton, Cabot, Alexander, and Maumelle.
Call James at (501) 258-5935 or email planitdirt@yahoo.com to get started.