How Much Soil to Fill a Hole

Filling Holes and Excavations

Whether you've had a tree stump removed, filled in an old fish pond, or need to level an uneven section of your yard, calculating the fill required is straightforward once you know the dimensions. A typical stump removal site of 2 metres by 2 metres with a depth of 500mm (half a metre) requires approximately 2 cubic metres of topsoil to fill and level the area for lawn or garden use.

Two cubic metres of topsoil weighs approximately 2.2 tonnes, a substantial load that requires bulk delivery. For filling deep holes, standard topsoil is usually the most economical choice, though you may want to top the final 100mm with garden mix if you're establishing a garden bed over the filled area.

Compaction Considerations

Fresh fill material will settle over time, particularly in deep holes. Order slightly more than your calculated volume to account for this, typically 10-15% extra for fills deeper than 300mm. Compacting the soil as you fill in layers helps reduce later settlement. Use a hand tamper or plate compactor if available, working in layers of roughly 150mm to achieve good compaction throughout the fill rather than just at the surface.

Layered Fill Approaches

For very deep holes, consider a layered approach that saves money while providing good growing conditions at the surface. Fill the lower portion with cheaper clean fill or rubble if available, then top with 200-300mm of quality topsoil. This technique works well for old swimming pool fills or significant excavations where using premium soil throughout would be unnecessarily expensive. Ensure any fill material you use is clean and free from contaminants, particularly if the area will support edible plants.

Filling an irregular shaped hole? Use our main soil calculator with the circle option for round stumps or estimate rectangular dimensions for complex shapes.