How flagstone is sold
Flagstone is natural stone split into flat slabs. It's sold by the ton, or by the pallet, which is usually 1–2 tons. Because pieces vary in thickness, suppliers quote coverage in square feet per ton: thinner stone covers more area.
Worked example
A 200 sq ft patio using standard 1.5–2 in stone at about 90 sq ft per ton, with 10% waste: 200 × 1.1 ÷ 90 = 2.4 tons.
Coverage by thickness
| Thickness | Typical coverage per ton | Good for |
|---|---|---|
| 1–1.5 in | 100–120 sq ft | Mortared patios on concrete |
| 1.5–2 in | 80–100 sq ft | Dry-laid patios and paths |
| 2–3 in | 60–70 sq ft | Stepping stones, heavy use |
Coverage also depends on the stone type (sandstone, limestone, slate, quartzite) and how tightly you fit the pieces. Ask your stone yard for their figure.
What goes under flagstone
For a dry-laid patio, dig out 6–7 in, lay 4 in of compacted crushed gravel, then 1 in of sand or stone dust to bed the stones. Fill the joints with sand, stone dust or polymeric sand, or plant creeping thyme between them for a softer look.
Frequently asked questions
How much area does a ton of flagstone cover?
Roughly 80–100 sq ft for standard 1.5–2 in stone. Thinner stone covers up to 120 sq ft, and thick stone 60–70 sq ft.
How many tons of flagstone for a 12 × 12 patio?
A 144 sq ft patio needs about 1.8 tons of standard flagstone with 10% waste.
Can I lay flagstone directly on dirt?
For stepping stones in a garden, yes. For a patio, a compacted gravel base keeps stones level and stops them rocking or sinking.
Last reviewed 2026-11-14. Material weights are typical industry averages and vary by supplier, moisture and compaction.