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Gravel & Aggregate Calculator

Fast, accurate tonnage estimates for UK decorative stone and driveways.

50 mm

Recommended: 40-50mm for driveways.

5%

Gravel Requirements

Buying in bulk? Loose loads (tipper trucks) are usually much cheaper than bags for orders over 10 tonnes.

The Definitive Guide to Gravel Driveways & Paths

Why Choose Gravel?

Gravel is one of the most cost-effective and attractive surfacing options in the UK. It is naturally permeable (meeting SuDS regulations), provides excellent security (due to the crunch sound), and is easy to install for DIYers.

However, getting the quantity right is vital. Order too little, and you'll have bare patches; order too much, and you'll have a mountain of stone left over on your lawn.

Gravel Coverage Specs

1 Tonne Covers (50mm depth)~12m²
Standard Bulk Bag850kg
Small Pre-pack Bag20kg - 25kg

Calculating the Perfect Depth

Depth is the most common mistake in gravel installation.

  • 1

    Too Shallow (under 30mm): The sub-base or weed membrane will show through, and the gravel will shift constantly.

  • 2

    Too Deep (over 60mm): Walking and driving will become difficult as you 'sink' into the stone. It becomes like walking on a beach.

The Sub-base & Membrane

For driveways, you MUST have a compacted sub-base of MOT Type 1. On top of this, always lay a heavy-duty weed membrane. This prevents your expensive decorative gravel from mixing with the soil and prevents weeds from taking root in the ground below.

Popular Decorative Stones

  • Cotswold Buff: Classic cream limestone.
  • Plum Slate: Flat, purple-toned stone.
  • Scottish Pebbles: Rounded, smooth river stones.
  • Golden Gravel: Hard-wearing flint mix.

Pro Tip: Gravel Grids

If you hate your gravel shifting or spreading onto the road, consider using Gravel Grids (Cellular Paving). These plastic honeycombs hold the gravel in place, making it solid enough for wheelchairs and heavy cars.

Gravel & Aggregate FAQ

Tonnage Disclaimer

Material densities vary between stone types. For example, slate is lighter than limestone. Our calculations use a standard aggregate density of 1.6 tonnes per m³. Always confirm the exact coverage with your supplier before ordering.

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