Gravel Calculators
Shed Foundation Gravel Calculator
A shed pad is a small, level, compacted gravel platform — sized bigger than the shed. Pre-set to crusher run at 4 inches; enter your pad dimensions (shed + 1 ft per side), not the shed's footprint.
A note on this estimate
The pad should extend about 1 ft past the shed on every side, and soft ground needs fabric or a deeper pad. Compaction reduces loose volume, so the delivered pile will look bigger than the finished pad.
Last updated: 7 November 2026 · Report an error
Building the pad
Order of operations matters more than tonnage: strip topsoil (it's organic and compressible — it will settle), level the subgrade, lay geotextile fabric on soft ground, then stone in compacted lifts. Check level across the finished pad — a shed racks on an out-of-level base.
Worked example: a 10 × 12 shed wants a 12 × 14 pad (168 ft²). At 4 inches of crusher run: 168 × ⅓ ft = 56 ft³ = 2.07 yd³ ≈ 3.3 tons — one small truckload, or order 3.6–3.8 tons to cover compaction.
Pad size by shed size
The pad is always bigger than the shed: extend it about 1 ft past the walls on every side, so rain dripping off the roof lands on gravel instead of eroding the edge, and you have a dry margin to stand on. That makes the pad 2 ft longer and 2 ft wider than the shed itself:
| Shed size | Pad size | Gravel needed |
|---|---|---|
| 6 × 4 ft | 8 × 6 ft | 16 ft³ · 0.59 yd³ · 0.95 t |
| 8 × 6 ft | 10 × 8 ft | 26.67 ft³ · 0.99 yd³ · 1.58 t |
| 8 × 10 ft | 10 × 12 ft | 40 ft³ · 1.48 yd³ · 2.37 t |
| 10 × 12 ft | 12 × 14 ft | 56 ft³ · 2.07 yd³ · 3.32 t |
Worked example: the middle row — an 8 × 10 ft shed on a 10 × 12 ft pad at 4 inches: 120 ft² × 0.333 ft = 40 ft³ = 1.48 yd³ ≈ 2.37 tons of crusher run. On soft ground go to 6 inches and add half as much again (60 ft³ ≈ 3.56 tons); the extra depth is cheaper than re-levelling a settled shed with doors that no longer close.
Build notes that decide whether the pad works: frame the pad with pressure-treated timber or edging boards levelled first — loose gravel has nothing to compact against without a frame; lay woven fabric on soft soil before the stone, not plastic; compact in two lifts rather than one 4-inch pour of stone; and finish the pad dead level, because a gravel pad is the one foundation you cannot shim later without lifting the shed.
Related tools & guides
Paver Base Calculator
Same compacted-base thinking for patios and walks.
Gravel Driveway Calculator
Layered bases for driven surfaces.
Crushed Gravel Calculator
Crusher run or a compactable crushed stone for the pad.
Patio Gravel Calculator
Level compacted surfaces, patio edition.
French Drain Gravel Calculator
Wet ground where the shed sits? Start here.
Gravel Cost Calculator
Price this pad at your supplier's rate.
Shed pad FAQ
How big should a gravel pad be for a shed?
At least 1 foot larger than the shed on every side — a 10×12 shed wants a 12×14 pad — so the floor frame sits fully supported and splash-off lands on stone, not soil. Enter the pad dimensions, not the shed's.
How deep should a shed gravel pad be?
4–6 inches of compacted crushed stone after compaction. On soft or poorly draining ground, go thicker or add geotextile fabric so the pad doesn't slowly sink into the mud it was meant to avoid.
What's the best gravel for a shed base?
Crusher run or a compactable ¾-inch minus crushed stone — the same family as a driveway base. It compacts into a level, stable platform. Washed stone stays loose and is hard to level; pea gravel is not a foundation.