Gravel Shed Base Calculator
Calculate tons of crusher run for a shed foundation pad using its 1.5 tons per cubic yard density, plus total material cost.
How this calculator works
A shed base is filled with crusher run by volume, so this calculator converts your pad’s length, width, and depth into cubic yards, then multiplies by crusher run’s compacted density of 1.5 tons per cubic yard to get the tons you need to order.
Formula: Cubic yards = (Pad length ft × Pad width ft × Depth ft) ÷ 27. Tons = Cubic yards × 1.5.
Worked example
A 12 ft × 10 ft shed pad (a 10 ft × 8 ft shed plus 1 ft of margin per side) at a 4-inch depth:
- Depth in feet: 4 ÷ 12 = 0.3333 ft
- Cubic yards: (12 × 10 × 0.3333) ÷ 27 ≈ 1.4815 yd³
- Tons: 1.4815 × 1.5 ≈ 2.22 tons
- At $40/ton, that’s $88.89 before waste.
Coverage reference
| Pad size | Tons needed (at 4 in) |
|---|---|
| 6 ft × 5 ft | 0.56 tons |
| 12 ft × 10 ft | 2.22 tons |
| 24 ft × 20 ft | 8.89 tons |
How to measure your shed pad
Measure your shed’s actual footprint length and width in feet, then add roughly 1 ft to each dimension so the finished pad extends past the shed’s edges on all sides. Use the compacted target depth from your plan, not the loose depth you’ll spread before running a plate compactor over it.
Frequently asked questions
What size should I make a gravel shed base compared to the shed itself?
Extend the gravel pad about 1 ft beyond the shed's footprint on every side. For a 10 ft × 8 ft shed, that means building a 12 ft × 10 ft pad — the extra margin keeps the shed's edges and runoff drip line supported and prevents the perimeter from crumbling under foot traffic or weather.
Why is crusher run the default material for a shed base instead of plain gravel?
Crusher run's mix of crushed stone and fines lets it compact into a firm, stable pad that won't shift under the shed's point loads, unlike washed gravel, which stays loose and can let a shed settle unevenly over time.
What depth of gravel does a shed base need?
4 inches compacted is a common minimum for a small to mid-size shed on reasonably firm native soil. Larger sheds, heavier contents, or soft/clay soil often call for 6 inches, sometimes with a geotextile fabric layer underneath to stop the base from sinking into the subgrade.
Do I need to level the ground before spreading gravel for a shed base?
Yes — excavate and level the area first, ideally to a slight crown or slope away from the shed for drainage, before adding and compacting the gravel. Building a gravel base over unlevel or unexcavated ground defeats much of the purpose of a proper foundation pad.
Should I compact the gravel before placing the shed on it?
Yes, always. Compact with a plate compactor after spreading and before setting the shed's skids or frame down, since an uncompacted base will settle unevenly under the shed's weight, potentially racking the structure or its door frame out of square.
Should I add waste when ordering gravel for a shed base?
Yes, the 10% waste toggle is reasonable to cover compaction settling and an imperfectly excavated pad edge.
Estimates only. Verify quantities with your supplier before purchasing.