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Slate chippings calculator

Work out how many bulk bags of slate chippings a bed or path needs.

Slate chippings calculator

Shape of the area
ft
ft
in
%
Use your supplier's density
kg/m3

Enter your measurements to see what to order.

One cubic metre of slate chippings weighs about 1.55 tonnes and covers about 20 square metres at 50mm.

How to work out how much slate chippings you need

  1. Measure the area in metres and multiply length by width.
  2. Pick a depth in mm and multiply it by the area to get a volume.
  3. Multiply the volume by the bulk density, 1550 kg per cubic metre for slate chippings, to get a weight.
  4. Divide the weight by your supplier's tonne or bulk bag to get what to order, and round up. Suppliers do not sell part bags.
  5. Add 10 percent. Covers settlement, uneven ground and the material lost around the edges. A second delivery for half a yard costs more than the extra you did not use.

How many tons in a cubic yard of slate chippings?

About 1.31 US tons, at 1550 kg per cubic metre. Because published densities run from 1400 to 1700, the honest answer is a range: between 1.18 and 1.43 tons per cubic yard depending on grading and how wet the load is.

How many cubic yards in a ton of slate chippings?

About 0.77 cubic yards. One tonne is about 0.65 cubic metres.

How much does slate chippings weigh?

Between 1400 and 1700 kg per cubic metre, a spread of 21 percent. Flat and platy, so it beds down thinner than round gravel at the same stated depth. The calculator above uses 1550, and you can replace it with your own supplier's figure.

5 published figures from 4 suppliers, read 2026-09-20.

SupplierPublished figureCondition
Mainland Aggregates LtdUKApprox 1.6 tonnes per cubic metreunstated
Northwest AggregatesUK1000kg covers 12m2 at a depth of 50mmunstated
AWBS LtdUKA full 850kg jumbo bulk bag will cover approximately 10-12m2 at a depth of 50mmunstated
Greenvale Products LtdUKA tonne bag covers 12m2 at 50mm deepunstated
Mainland Aggregates Ltd (coverage figure, same product page)UK1 x Bulk Bag will cover approx 10sqm at 50mm depth; FAQ on same page states 'one of our Bulk Bags will cover 12m2 at 40mm depth'unstated

What you can order slate chippings in

PackWhereSize
850kg bulk bagUK850 kg (suppliers state 700 to 1000 kg)
25kg bagUK25 kg
tonneUK, AU1,000 kg

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