Gravel shed base, step by step
A timber frame, weed membrane, 100 mm of compacted sub-base and 50 mm of gravel on top. For an 8 x 6 ft shed it is two days for one person.
Eight steps in four stages
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Steps 1 and 2: mark out and dig
Peg out 150 mm wider than the shed all round; check the diagonals match. Dig out 150 mm, roots and all.
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Steps 3 and 4: build and level the frame
Screw four 150 x 47 mm treated boards into a box, stake it every metre and level it both ways.
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Steps 5 and 6: membrane and sub-base
Lay membrane with 150 mm overlaps. Spread MOT Type 1 in two 50 mm layers, compacting each.
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Steps 7 and 8: gravel and bearers
Fill to the frame's edge with 20 mm angular gravel. Lay treated bearers, check the level, set the shed.
Materials list for an 8 x 6 ft shed
For a base of 2.6 x 2.0 m. Picks marked as examples show the kind of product to look for.
- Treated timber, 150 x 47 mm2 lengths of 4.8 m
- Timber stakes, 50 x 50 x 600 mm8
- Exterior screws, 75 mm1 box of 100
- Weed membrane, 100 g/m², example pick1 roll, 2 x 10 m
- MOT Type 1 sub-base1 bulk bag
- Angular gravel, 20 mm1 bulk bag
- Treated bearers, 75 x 50 mm, example pick5 lengths of 2.4 m
- Plate compactor, or a hand tamper1 day's hire
Gravel base costs
A worked example for the 2.6 x 2.0 m base above, about £310 in all.
| Item | Quantity | Example price |
|---|---|---|
| Treated timber, 150 x 47 mm | 2 x 4.8 m | £36 |
| Timber stakes | Pack of 8 | £14 |
| Exterior screws, 75 mm | Box of 100 | £8 |
| Weed membrane | 2 x 10 m | £15 |
| MOT Type 1 sub-base | Bulk bag | £75 |
| Angular gravel, 20 mm | Bulk bag | £80 |
| Treated bearers, 75 x 50 mm | 5 x 2.4 m | £35 |
| Plate compactor hire | 1 day | £45 |
| Total | £308 |
Example prices from builders' merchants in autumn 2026. Delivery of bulk bags is often extra; a hand tamper saves the hire.
Gravel base questions
How deep should a gravel shed base be?
About 150 mm: 100 mm of compacted sub-base and 50 mm of gravel. On clay or soft ground, dig another 50 mm.
Can a shed sit straight on gravel?
Not on the stones alone. Set the floor on treated bearers or a plastic grid, so air moves under it.
Which gravel suits a shed base?
Angular, 10 to 20 mm. The edges lock under weight; round pea shingle rolls and lets bearers sink.
Gravel or a concrete shed base?
For a timber shed up to about 10 x 8 ft, usually: it costs less and drains. Pour concrete for a heavy workshop or a log cabin.
