Which sand do I need?
Sand is not all the same. The size and shape of the grains decide what it is good for.
Sharp sand
Coarse and gritty. Packs firm and drains well.
Best for paving beds and lawns
Building sand
Fine and soft. Mixes smoothly with cement.
Best for mortar
Play sand
Washed, fine and free of sharp bits.
Best for sandpits
Planning the rest of the job? Use the Pea gravel calculator and the Stone calculator too.
How deep should sand be?
How does the calculation work?
Tonnes = area (m²) × depth (m) × density (t/m³)
A patio 4 m by 2.5 m with a 5 cm sand bed: 10 × 0.05 = 0.5 m³. At 1.6 t/m³ that is 0.8 tonnes, or 32 bags of 25 kg.
Wet sand is noticeably heavier than dry. If your sand has been stored outside, expect it to weigh up to 20% more.
Bags or bulk?
Bags are fine for top dressing and small repairs. For a patio or a big sandpit, a bulk bag is cheaper and saves dozens of trips to the car.