MOT Type 1 calculator
Work out how much MOT Type 1 a sub-base needs, at the 150mm, 100mm and 75mm depths for driveways, patios and paths.
MOT Type 1 calculator
Use your supplier's density
You need
- Volume
- Weight
- Area
| Order by | Exact | Order, rounded up for anything sold in whole bags |
|---|
Enter your measurements to see what to order.
One cubic metre of mot type 1 weighs about 1.9 tonnes and covers about 7 square metres at 150mm.
How to work out how much mot type 1 you need
- Measure the area in metres and multiply length by width.
- Pick a depth in mm and multiply it by the area to get a volume.
- Multiply the volume by the bulk density, 1900 kg per cubic metre for mot type 1, to get a weight.
- 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.
- Add 20 percent. Type 1 is ordered loose and laid compacted, and it loses roughly a fifth of its volume under a compactor. That is why this default is higher than for decorative gravel.
How many tons in a cubic yard of mot type 1?
About 1.6 US tons, at 1900 kg per cubic metre. Because published densities run from 1600 to 2200, the honest answer is a range: between 1.35 and 1.85 tons per cubic yard depending on grading and how wet the load is.
How many cubic yards in a ton of mot type 1?
About 0.62 cubic yards. One tonne is about 0.53 cubic metres.
How deep should mot type 1 be laid?
| Use | Depth | What the supplier says |
|---|---|---|
| Driveway | 150mm | Mainland Aggregates: 150mm depth when used as a driveway sub-base for car traffic. |
| Patio | 100mm | Mainland Aggregates: patio sub-bases laid at 100mm depth. |
| Path | 75mm | Mainland Aggregates: path sub-bases should be 75mm depth. |
| Shed base | 100mm to 150mm | Mainland Aggregates gives 100mm for patios and 150mm for vehicle loading; a shed base sits between the two. |
How much does mot type 1 weigh?
Between 1600 and 2200 kg per cubic metre, a spread of 38 percent. Ordered loose, laid compacted. The low end is the loose delivered figure and the high end is compacted in place. The calculator above uses 1900, and you can replace it with your own supplier's figure.
5 published figures from 5 suppliers, read 2026-09-20.
| Supplier | Published figure | Condition |
|---|---|---|
| Earth Haulage LtdUK | 1.6 tonne per m3 loose; 1.8 tonne per m3 compacted | Both conditions stated explicitly and separately on the page: loose 1.6,... |
| Soils & StoneUK | 2.2 tonnes per m3 | Compacted |
| Armstrongs GroupUK | 2.0 to 2.2 tonnes per cubic metre; common working estimate 2.1 tonnes per m3 | Unstated |
| Mainland Aggregates LtdUK | Approx 2 tonnes per cubic metre | Unstated |
| Storefield GroupUK | MOT Type 1 / subbase: 1.85-2.00 t/m3 | Unstated for the number itself |
What you can order mot type 1 in
| Pack | Where | Size |
|---|---|---|
| 850kg bulk bag | UK | 850 kg (suppliers state 700 to 1000 kg) |
| 25kg bag | UK | 25 kg |
| tonne | UK, AU | 1,000 kg |
MOT Type 1 and road base
In the US trade the same material is sold as road base, ordered in cubic yards and tons, so the road base calculator works in those units and at those depths.