Concrete and asphalt are only as good as what's under them. We build and compact the subgrade and gravel base for shop floors, building pads, driveways and RV pads, so the slab or paving goes down on something solid.
Compaction for Pads, Driveways and Paving in Boise
The concrete crew is coming Thursday. The asphalt company has you penciled in for next week. Before either one starts, somebody has to get the ground under the work firm, flat and at the right height. That's the part we do.
We build compacted pads and base for homeowners, builders and businesses in Boise, Star, Kuna, Middleton, Parma and Caldwell. Acreage owners call us for shop pads and long gravel drives. Builders call for building pads and garage slabs. If you're more curious about why soil settles and how moisture and lifts work, our soil compaction page goes into that.
What We Compact
Building pads and shop floors
A shop or garage slab needs a level pad that won't settle under a truck, a lift or a loaded workbench. We strip the topsoil, fill and compact to the elevation on the plans, then place and roll the gravel base. For the dig itself, see slab excavation.
Driveways
Gravel drives, plus the base under new concrete or asphalt drives. Long driveways on acreage around Star and Middleton often cross soft field ground and need more base than people expect. See excavation for driveways.
RV pads and parking areas
An RV or a loaded trailer puts a lot of weight on a few small spots. A thin layer of gravel over loose topsoil ruts the first time it gets wet. An RV pad needs the soft material dug out and a real compacted base underneath.
Paving base
Asphalt and concrete contractors want a firm, graded base at a set depth below finished surface. We prep it to their numbers. See paving job site preparation. A concrete crew will give us the depth below the top of their forms. An asphalt crew will want the base graded to the same slope as the finished surface, so the asphalt goes down at an even thickness and sheds water the way it should.
Road Base and Gravel
What goes under the slab matters as much as how it's packed. Most jobs use crushed road base, often 3/4-inch minus, because the angular pieces lock together when they're compacted. On soft or clay subgrade, a coarser pit run layer sometimes goes down first, and a geotextile fabric can keep the gravel from working down into the clay over time.
Round river rock looks like gravel but doesn't lock up. It rolls. It drains well, which has its uses, but on its own it isn't a good base for a slab or a driveway. Digs near the Boise River turn up plenty of it, and it's tempting to reuse. It's better put to work where drainage matters more than strength, with crushed base brought in for the part that carries weight.
Base thickness depends on the load and the soil underneath. A sidewalk and an RV pad on clay don't need the same section. We'll talk it through with you or follow the spec from your engineer or builder.
Proof Rolling
Before base goes on, and again before concrete or paving, we look for soft spots. A proof roll means driving a heavy loaded truck or machine slowly across the subgrade and watching. Firm ground barely moves. Soft ground ruts, or pumps, flexing up and down as the wheels pass.
Pumping areas get dug out and replaced with better material, or dried out and recompacted. Catching them now costs a few loads of gravel. Catching them after the pour costs a cracked slab. On field ground and old pasture, soft spots often line up with old irrigation ditches, low corners where water used to sit, or places where livestock churned the ground.
What Inspectors and Builders Look For in Boise
Requirements vary by city and by job, but the checks on a pad or base are pretty consistent:
- No pumping or rutting under a loaded truck
- Grade and elevation that match the plans or the forms
- Base material and thickness as specified
- No frozen ground, standing water or mud in the subgrade
- Density test results from an independent testing lab, when the plans or the engineer call for them
Commercial work and engineered building pads often require lab testing. Many residential pads don't. If yours does, we schedule our lifts around the lab's site visits so nobody is waiting.
What We Need From You Before Base Work
A few details up front keep the pad from being built to the wrong height or the wrong section:
- Plans or a site plan showing the pad size and finished floor or surface elevation
- Contact info for your concrete or paving contractor, and their target start date
- Any base thickness or material spec from your engineer, builder or plans
- Whether density testing is required, and who the testing lab is
- A clear route for gravel trucks to reach the pad and dump close to it
Compacting Right Before Concrete or Asphalt
A base that was rolled tight three weeks ago may have been rained on, driven over by the framers or dug through by the plumber. We like to do the final grade and roll close to the pour or paving date, and we coordinate with your concrete or asphalt contractor so the base is ready when they pull up.
We don't pour concrete or lay asphalt ourselves. We get the ground ready for the crews who do, and we'd rather come back for a quick touch-up roll than have them place material on a base that's gone soft.
Why Hire Ultimate Excavation LLC
We're an Idaho registered contractor (RCE-65836) with a 5.0 rating on Google. Our reviews mention quick bids and getting to the job before the rains came. With base work, that timing is often the difference between rolling dry gravel and waiting a week for mud to dry. Call (208) 697-2429 or request a free estimate.
