Dedicated Project Estimator
Concrete Slab Sub-Base Gravel Calculator
Calculate crushed stone #57 and road base required beneath residential concrete slabs and footings.
⚡ Pre-configured Presets 🚚 Dump Truck Delivery Breakdown 📋 Quarry Order Specs Generator 🛡️ Compaction & Settling Buffer
⚡ Instant Scenario Presets (1-Click Auto-Fill):
1. Select Project Shape
Enter positive numbers for all dimensions and depth.
Unit System:
2. Enter Dimensions
Standard path: 2.5-3", Driveway: 4-6", Drainage: 8-12"
3. Select Gravel Aggregate & Density
4. Add Waste & Compaction Buffer
TOTAL GRAVEL NEEDED
2.72 TONS
5,444 lbs total weight Bulk Quarry Volume & Truck Loads
Volume (Cubic Yards): 1.94 cu yds
Volume (Cubic Feet): 52.50 cu ft
Estimated Delivery Truck Loads:
🚛 Tri-Axle (15T): 1 load 🚚 Tandem (10T): 1 load 🛻 Single Axle (5T): 1 load
Retail Bagged Order (Store Pickup)
0.5 cu ft Bags (Home Depot/Lowe's): 105 Bags
50 lb Bags: 109 Bags
Estimated Cost Comparison
Bulk Material Cost: $109 - $177
Bulk Delivery Freight (Est): $75 - $120
Total Bagged Retail Est: $473 - $630
🛠️ Interactive Tool
Gravel Layer & Excavation Cross-Section Simulator
Visualize multi-layer ground excavation, plate compaction settling, and dump truck hauling logistics in real-time.
2.0 inches
1" (Thin) 2.5" (Standard) 6" (Heavy)
4.0 inches
0" (None) 4" (Standard Base) 12" (Heavy Drainage)
600 sq ft
50 sq ft 1,000 sq ft 2,500 sq ft
Compaction Shrinkage Analysis (+18%)
To achieve a final compacted depth of 6.0 inches, you must spread 7.1 inches of loose uncompacted aggregate before running the plate compactor.
Cross-Section Elevation Profile
Ground Level (Grade 0.0")
🪨 Surface Layer: Washed #57 / Pea Stone 2.0 in
━━━━ Non-Woven Geotextile Separation Fabric ━━━━
🏗️ Sub-Base Course: Compacted Crusher Run / DGA 4.0 in
🌱 Native Subgrade Soil (Compacted Loam/Clay) Excavation Floor
0"
Total: 6.0" Depth
6.0"
Hauling Capacity 1 Tandem Truck
Wheelbarrow Trips 41 Trips
Total Material Weight 5.00 Tons
Recommended Depth & Base Specifications for Concrete Slab Sub-Base Gravel Calculator
Selecting the proper installation depth is the single most critical factor in preventing premature rutting, sinking, or weed breakthrough.
| Layer / Application | Recommended Depth | Stone Aggregate Type | Contractor Notes |
|---|---|---|---|
| Sidewalk & Patio Slab Base | 4 Inches | Crushed Stone #57 | Level drainage layer preventing frost heave under 4" concrete. |
| Garage Floor / Heavy Driveway | 6 Inches | Compacted Crusher Run | High density sub-base supporting vehicle loads and preventing structural cracks. |
💡 Contractor Installation Pro Tips
- A uniform gravel sub-base prevents slab thickness variations that cause stress cracks during curing.
- Vapor barrier (10-15 mil poly) should be placed over the gravel before pouring indoor concrete floors.
Frequently Asked Questions About Concrete Slab Sub-Base Gravel Calculator
Do you need gravel under a concrete slab?
Yes. Gravel provides a stable, non-settling capillary break that prevents groundwater from wicking into the concrete and causing winter frost cracks.
Missing a Stone Type or Have Feedback?
We update density presets and formulas regularly based on local quarry feedback.