The quick answer: for a new lawn, lay 4 to 6 inches (100–150 mm) of topsoil. At 4 inches, you need about 12.3 cubic yards for every 1,000 sq ft. In metric, 1 m³ covers 10 m² at 100 mm deep. Add around 10% because topsoil settles.
This guide covers the formula, a coverage table for common depths, and how many bags you would need for smaller jobs. For an instant figure in cubic yards, m³, tonnes or bags, use the topsoil calculator.
Topsoil coverage at a glance
| Depth | 1 cubic yard covers | Depth | 1 m³ covers |
|---|---|---|---|
| 1 in | 324 sq ft | 25 mm | 40 m² |
| 2 in | 162 sq ft | 50 mm | 20 m² |
| 4 in | 81 sq ft | 100 mm | 10 m² |
| 6 in | 54 sq ft | 150 mm | 6.7 m² |
How to work it out
- Measure the area in square feet or square metres. Split odd shapes into rectangles and add them up.
- Multiply by the depth. Convert inches to feet (÷ 12) or millimetres to metres (÷ 1,000) first.
- Convert cubic feet to cubic yards by dividing by 27.
- Add 10–15% for settling and uneven ground.
Worked examples
US lawn: 1,000 sq ft at 4 inches deep.
- Volume: 1,000 × (4 ÷ 12) = 333 cubic feet
- Cubic yards: 333 ÷ 27 = 12.3 yd³
- With 10% extra: about 13.5 cubic yards
UK lawn: 50 m² at 100 mm deep.
- Volume: 50 × 0.1 = 5 m³
- With 10% extra: 5.5 m³
- Weight: at about 1.3 tonnes per m³, that is roughly 7 tonnes
How deep should topsoil be?
| Job | Recommended depth |
|---|---|
| Top dressing an existing lawn | 1/4–1/2 in (6–12 mm) |
| Levelling low spots | 1–2 in (25–50 mm) at a time |
| New lawn from seed or turf | 4–6 in (100–150 mm) |
| Flower beds and borders | 6–8 in (150–200 mm) |
| Vegetable beds and raised beds | 8–12 in (200–300 mm) |
Grass roots do most of their work in the top few inches, but a deeper layer of good soil holds water better and helps the lawn survive dry spells.
How much does topsoil weigh?
Dry topsoil weighs roughly 1 to 1.1 tons per cubic yard, or about 1.2–1.4 tonnes per m³. Wet soil can weigh much more. This matters if you are collecting it in a trailer or ordering by weight: a small trailer or pickup can often carry less than one cubic yard safely.
Bags or bulk?
Bagged topsoil is handy for small jobs but gets expensive quickly.
- A 1 cu ft bag: 27 bags make one cubic yard.
- A 0.75 cu ft bag: 36 bags make one cubic yard.
- A 25 litre bag: 40 bags make one m³.
- A bulk bag in the UK is usually close to 1 m³, or about 0.8–1 tonne.
For anything over about one cubic yard or one cubic metre, bulk delivery is usually far cheaper per unit than bags.
Raised beds
For a 4 × 8 ft raised bed 12 inches deep, the volume is 4 × 8 × 1 = 32 cubic feet, or about 1.2 cubic yards. A 1.2 × 2.4 m bed 300 mm deep holds 0.86 m³. Many gardeners fill raised beds with a mix of topsoil and compost rather than topsoil alone.
Tips before you order
- Ask for screened topsoil. It has had stones and roots removed and spreads much more easily.
- Loosen the ground underneath before spreading, so the new soil does not sit on a hard layer.
- Spread and rake the soil, then firm it by walking over it before laying turf or sowing seed.
- Plan where the delivery will be tipped. A large load can block a driveway for a day or two.
Frequently asked questions
How much topsoil do I need for 1,000 sq ft?
About 6.2 cubic yards at 2 inches, 12.3 cubic yards at 4 inches and 18.5 cubic yards at 6 inches, before adding extra for settling.
Can I lay turf on 2 inches of topsoil?
It will take, but 4 inches or more gives much better, drought-resistant results, especially on clay or stony ground.
How much grass seed do I need after the topsoil?
That depends on the seed mix. Our grass seed and turf calculator gives the amount for your lawn size.
Related: the DIY Project Budget & Materials Planner turns your measurements into quantities, costs and a shopping list.
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