Service

Subgrade Preparation Contractor in Moore, OK

Pads and paving subgrade built in lifts, at grade and at density, ready for the testing lab.

Every slab, parking lot and drive is only as good as the ground under it. 365 Excavation & Land Solutions prepares subgrade for commercial pads, parking lots and new construction across Moore, Oklahoma City, Norman, Edmond, Midwest City and Del City.

Central Oklahoma clay swells when it is wet and shrinks when it dries. Subgrade that is not built in lifts at the right moisture and compacted to the engineer's spec is how you end up with cracked slabs and failed asphalt a year after the ribbon cutting. We build it right the first time and have it ready for testing before the concrete or paving crew shows up.

We coordinate with your testing lab and paving contractor so the pad is at grade, at density, and ready on the day the next crew is scheduled.

Building pad with subgrade cut and prepped to grade on a commercial site

Guide

Undercut and Replace vs Stabilized Subgrade on Oklahoma Clay

Central Oklahoma clay swells when it is wet and shrinks when it dries. The geotechnical report usually answers it one of two ways under a building pad or parking lot. Here is what each one means on the ground.

Read: Undercut vs Stabilized Subgrade

More planning guides

Latest Build

Small Sliders, Midwest City — Demo to Paving-Ready

5 photos of this work from our job sites, in the order it gets built.

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Featured Work

Commercial Site Work — From Tear-Out to Paving-Ready

9 photos of this work from our job sites, in the order it gets built.

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Storm Sewer

Storm Sewer Install — Start to Finish

11 photos of this work from our job sites, in the order it gets built.

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What's Included

Commercial and residential building pads
Parking lot and drive subgrade
Removal and replacement of unsuitable soils
Moisture conditioning and compaction in lifts
Fine grading to plan elevation and slope
Coordination with testing labs and paving crews

Why It Matters

Built for Oklahoma clay, not against it
Ready for density testing on the date we said
Fine grade that lets the paving crew hit its thickness
Same crew that did the earthwork, so nothing is re-cut

Our Process

Proof the existing ground

We check what is under the site, remove unsuitable material, and confirm the pad or paving section against the plan.

Condition the moisture

Material is brought into the moisture range the spec calls for, because clay that is too wet or too dry will not reach density no matter how many passes it gets.

Place and compact in lifts

Fill goes down in thin lifts and each lift is compacted before the next one goes on top of it.

Fine grade, ready for testing

The surface is trimmed to plan elevation and slope so base and paving thicknesses come out right, and the pad is ready for the lab.

Subgrade Preparation Gallery

Finished building pad with subgrade prepped

Skid steer fine-grading the Texas Roadhouse parking lot at dusk

Dozer fine-grading between new curb lines

Red-dirt pad graded with grade stakes in place

Skid steer working a rock base section on a cleared lot

Excavator and graded subgrade under evening light

Frequently Asked Questions

What is subgrade preparation?

It is building the soil layer that sits under a slab, base course or asphalt. The subgrade has to be at the right elevation and compacted to spec, or whatever goes on top of it will crack and settle.

Do you work with the testing lab?

Yes. We build the pad to the engineer's spec and have it ready for density testing so concrete or paving is not held up. The testing itself belongs to an independent lab, not to us.

Why does Oklahoma clay matter so much?

Expansive clay moves with moisture. Building subgrade in lifts at the right moisture and density, and following the geotechnical report on how the pad is treated, is what keeps that movement from cracking your slab or pavement.

Can you treat or replace bad soil under a pad?

Where the geotechnical report calls for removing and replacing unsuitable material, or for a select fill cap, we do that as part of the subgrade scope. Send the report with the plans and we will price what it actually asks for.