Step-by-step gravel shed foundation

The short answer

Mark out a pad 12 inches bigger than your shed on every side. Dig out 4 to 6 inches of soil, compact it, lay landscape fabric, and build a frame of pressure-treated 4x4s staked with rebar. Fill it with ¾-inch crushed stone in 2-inch layers, compacting each one, then screed it level. For a 10 × 8 ft shed, budget roughly $485–$750 and one full weekend.

Gravel is the base we suggest to most first-time shed owners. It costs a fraction of a concrete slab, needs no mixing or curing, drains well so the floor stays dry, and you can do it with hand tools and one rented machine. It suits most timber, metal and plastic sheds up to about 12 × 10 ft on reasonably flat ground.

Before you dig

• Call before you dig. Have buried cables and pipes marked first. In the US, dial 811; elsewhere, contact your utility companies.
• Check local rules. Some areas limit shed size, height or distance from a boundary. A quick call to your local planning or building office is worth it.
• Pick a spot that drains. Avoid the lowest point of the garden, where water collects. Leave at least 2 ft behind the shed so you can reach it to paint.
• Get the shed’s exact footprint. Use the manufacturer’s base dimensions, not the roof overhang size in the listing title.

The steps

1. Mark out the pad

   Add 12 inches to each side of the shed’s base size. A 10 × 8 ft shed needs a 12 × 10 ft pad. Knock in a stake at each corner and run string lines between them.

   Measure both diagonals. When they match, the pad is square.

2. Strip the turf and dig out

   Remove grass, roots and soft topsoil inside the strings, 4 to 6 inches down. Dig to firm ground. If the ground slopes, dig into the high side rather than building up the low side.

   Stack the turf upside down somewhere out of the way. It rots down into good topsoil within a year.

3. Level and compact the soil

   Rake the bottom roughly level, then run the plate compactor over it two or three times. Fill any soft spots with stone and compact again. A firm bottom is what stops the base sinking later.

4. Build and set the timber frame

   Cut pressure-treated 4x4s (rated for ground contact) to the pad size and lay the first course in the trench. Stagger the corners, then lay the second course on top so the joints overlap, and fix the two courses together with 10-inch timber screws.

   Check the frame is level along each side and across both diagonals. Pack or dig under the timbers until it is.

5. Pin the frame down

   Drill ½-inch holes through both courses every 3 to 4 ft and near each corner, then drive 24-inch lengths of rebar through them into the ground with a sledgehammer, until they sit flush with the top.

6. Lay landscape fabric

   Line the inside of the frame with woven landscape fabric, overlapping joins by 6 inches and running it a little way up the timbers. It keeps the stone from sinking into the soil and slows weeds.

7. Fill with stone in layers

   Tip in ¾-inch crushed, angular stone (sometimes sold as #57 stone or clean ¾-inch). Spread a 2-inch layer, compact it, and repeat until the stone is level with the top of the frame.

   Layers matter. One deep layer compacts only at the surface and settles unevenly under the shed.

8. Screed and check level

   Drag a straight 2x4 across the top of the frame to strike off the stone, filling any hollows as you go. Check with a 4 ft level in several directions. Within ¼ inch over the whole pad is good enough for most sheds.

9. Place the shed

   Set the shed on its bearers so there are roughly 12 inches of gravel showing on every side. That margin carries roof run-off away from the walls instead of splashing it back onto them.

Materials list

Quantities for a 10 × 8 ft shed on a 12 × 10 ft pad, 6 inches deep. Tick things off as you buy them; your ticks are saved on this device.

• Pressure-treated 4x4 timbers, ground-contact rated, 12 ft4
• Pressure-treated 4x4 timbers, ground-contact rated, 10 ft4
• ¾-inch crushed angular stone (not pea gravel)2.5 cu yd, about 3.5 tons
• Woven landscape fabric120 sq ft, plus overlap
• ½-inch rebar, cut to 24 in12 pieces
• 10-inch exterior timber screws16
• Wooden stakes and string line4 stakes, 50 ft line
• Plate compactor, rented1 day
• Tools you probably own: spade, shovel, rake, wheelbarrow, 4 ft level, tape measure, sledgehammer, drill, circular saw—

What it costs

Rough 2026 US prices from big-box stores and local stone yards. Stone and delivery vary a lot by region, so phone two yards before you order.

Estimates only, for planning. They assume you do the work yourself and already own basic hand tools.

Example kit

The kind of thing to look for. These are example picks to show what to buy, not tested recommendations, and links may earn us a commission.

FAQ

Base sorted? Check the shed before you buy it.

The free Shed Review Guide is a printable checklist for judging timber, roofing, floors and fixings on any shed, in store or online.

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