How much gravel do I need for a shed base?

For a typical pad sized 1 ft larger than the shed in each direction at 4 inches deep, an 8'×10' shed needs about 1.22 yd³ or 1.7 tons of #57. Bigger sheds scale linearly.

What size should a shed gravel pad be?

1 foot wider than the shed in each direction. An 8'×10' shed gets a 9'×11' pad. The extra space catches roof drip-line water and gives you working room around the perimeter.

How deep should the gravel pad be?

4 inches minimum, compacted. Bump to 6 inches for heavy workshop sheds or soft / clay soils. Don't go thinner than 4 inches — the pad won't drain or stay level.

What's the best gravel for a shed base?

#57 crushed stone is the default — drains well, compacts firm enough for a shed, widely available. CA6 or 21AA are also good and pack even tighter, but #57 is more forgiving if you don't have a plate compactor.

Do I need fabric under a shed gravel pad?

Yes — woven geotextile (the heavy black stuff, not landscape fabric). It prevents the gravel from sinking into the soil and prevents weeds from coming up through the pad.

Can a shed sit directly on gravel without a frame?

Pre-built sheds on skids can sit directly on a leveled gravel pad — that's the most common DIY install. For site-built sheds, a treated-timber frame on top of the gravel gives you a level reference and prevents the pad from spreading.

Is gravel cheaper than concrete for a shed base?

Much cheaper. A 100 sq ft pad costs ~$100 in #57 gravel vs ~$400–$600 in concrete. Gravel also drains better, which extends the shed's life.

How big should a shed gravel pad be?

Make the pad 1 foot wider and 1 foot longer than the shed footprint, so there's a 6-inch border of stone on every side. This handles drip-line runoff and prevents the shed's edge from sitting on bare soil that erodes. For a 10×12 shed, build an 11×13 pad.

Do I need to compact the shed pad?

Yes — light compaction with a hand tamper or rented plate compactor is enough for #57 stone (it locks together when compacted). For dense-grade base materials (CA6, ABC, crusher run), full machine compaction in 2-inch lifts is required to get the load-bearing strength. Skipping compaction is the #1 cause of pad settling and shed doors that won't latch a year later.

Shed Base Gravel Calculator — Tons & Yards

How this calculator works for shed bases

A shed pad is sized 12 inches larger than the shed in each direction — so an 8'×10' shed gets a 9'×11' pad. The extra ring of gravel keeps roof drip-line water away from the wood, prevents undermining of the corners, and gives you somewhere stable to step when working on the shed.

Material is 4 inches of #57 crushed stone, compacted with a hand tamper or rented plate compactor. #57 is the right choice because it drains while still being stable enough to hold a shed's weight evenly. CA6 or 21AA are also fine if your supplier has them on hand.

Build a frame to contain the gravel

Pressure-treated 4×4 or 4×6 timbers staked at the corners give you a level reference, contain the gravel, and prevent the pad from spreading out over years. Level the frame first, then dump and rake gravel inside it.

Recommended depth & material

Use	Depth	Material	Notes
Standard shed (under 200 sq ft)	4"	#57 crushed stone	Pad 12" wider than shed in each direction.
Heavy shed (workshop, full of tools)	4" – 6"	#57 over CA6 base	Two layers if soil is soft.
Shed on slope (cut & fill)	4" minimum on uphill side	#57 with retaining timbers	More gravel needed on downhill side.
Concrete slab under shed	4" gravel + 4" concrete	#57 base, concrete on top	Use the concrete-mix calculator for the slab.
Pre-built shed on skids	4" pad	#57 crushed stone	Skids rest on gravel; no fasteners.

How to measure for a shed base

Don't measure the shed — measure the pad you'll build under it. The pad is bigger than the shed by 12 inches in each direction.

Add 1 ft to each dimension of the shed. An 8 ft × 10 ft shed gets a 9 ft × 11 ft pad. A 10 ft × 12 ft shed gets an 11 ft × 13 ft pad. The extra foot is the drip-line buffer.
Stake and level the frame. Set treated timbers at the corners using a string level or laser level. The pad must be flat — any tilt becomes a tilted shed.
Excavate to depth. Remove sod and soil to a depth of 4 inches inside the frame. Save the soil for grading later.
Lay geotextile fabric. Woven geotextile (not landscape fabric) over the soil before the gravel goes in. Stops the gravel from disappearing into the dirt over years.
Set depth in the calculator to 4 inches. And confirm the material is #57 crushed stone (the default).
Add 10% buffer. Compaction takes about 15% out of #57 stone. The 10% buffer keeps you from running short.

Worked example: pad for an 8' × 10' shed

An 8 ft × 10 ft shed needs a 9 ft × 11 ft pad = 99 sq ft.

Volume: 99 × 4 ÷ 324 = 1.22 yd³
Weight: 1.22 × 2,750 ÷ 2,000 = 1.68 tons
With 10% buffer: ~1.85 tons of #57 stone.
Cost: at $50/ton delivered, about $95 in stone, plus an $80–$150 delivery fee. Total under $250 for the foundation, beating concrete by an order of magnitude.

For a 10' × 12' shed with an 11' × 13' pad (143 sq ft), you'd need ~2.4 tons of #57 — about $130 in stone.

Shed Base Gravel Calculator