What is the difference between Type 1 and Type 3?

Type 1 is well graded with fines included, so it compacts to a dense load-bearing layer. Type 3 is open graded with reduced fines, so it drains more freely. Type 3 is used where drainage through the layer matters.

Can I use recycled Type 1 instead?

Often yes, and it is considerably cheaper. But the specification governs — substituting recycled material into a spec calling for primary aggregate is a defect risk, not a saving.

Why do suppliers quote such different prices?

Because aggregate is heavy and low in value per tonne, so haulage distance is a large share of the delivered cost. Order volume, account terms and how recently the rate was agreed also move the figure. The nearest supplier often beats the cheapest headline rate.

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MOT Type 1: what it is, where it goes, and how it is priced

Q: How much MOT Type 1 do I need per square metre?

Work out volume first: area in square metres multiplied by compacted depth in metres gives cubic metres. Compacted Type 1 is commonly taken at roughly two tonnes per cubic metre for ordering, though this varies by source rock — confirm with your supplier. So 100 square metres at 150mm is about 15 cubic metres, or roughly 30 tonnes.

Supreme Building Services · in Materials & procurement

MOT Type 1 is a graded crushed aggregate used as a load-bearing sub-base under roads, driveways, car parks and slabs. It compacts to a dense, stable layer because it contains a full range of particle sizes from around 40mm down to dust. It is sold by the tonne, priced largely by how far it has to travel, and is the single most common bulk material on a groundworks job.

What it actually is

"MOT" comes from the old Ministry of Transport specification. Type 1 is a well-graded crushed rock, concrete or slag: a continuous spread of particle sizes so the smaller fragments fill the voids between larger ones. That grading is the whole point — it is what lets the layer compact to something that carries load and does not move.

Type 1, Type 3 and recycled

Material	Character	Typically used for
Type 1	Well graded, fines included, compacts dense	Roads, driveways, car parks, slab sub-base
Type 3	Open graded, reduced fines, free draining	Where drainage through the layer matters
Recycled Type 1	Crushed concrete and masonry	Cost-sensitive fill where spec allows
6F2	Coarse crushed fill	Bulk filling, capping layers

Recycled material is considerably cheaper and entirely appropriate in many situations — but the specification governs. Substituting it into a spec that calls for primary aggregate is not a saving, it is a defect waiting for an inspection.

How much do you need?

Volume first, then weight. Area in square metres, multiplied by compacted depth in metres, gives cubic metres. Compacted Type 1 is commonly taken at roughly two tonnes per cubic metre for ordering purposes — confirm with your supplier, since it varies by source rock.

A worked example: 100m² at 150mm compacted depth is 15m³, so roughly 30 tonnes. Allow for the material consolidating during compaction — ordering to the exact calculated figure tends to leave you short.

Why two quotes differ by more than they should

Type 1 is heavy and low in value per tonne, so haulage is a large share of what you actually pay. The nearest quarry or depot frequently beats a cheaper headline rate once it is on the ground. Order volume, account terms and how recently the rate was agreed do the rest — covered in full in materials and procurement.

That is why a delivered price and a list price are different things, and why comparing headline rates between suppliers is close to meaningless without knowing where each is coming from.

We supply Type 1, Type 3, recycled Type 1 and 6F2 to site through vetted suppliers at the rate quoted, and price sub-base laid and compacted where the job needs the whole package rather than a delivery. To see what a job's sub-base comes to, run the quantities through the BOQ pricer.

Need a delivered price?

Quantities, site postcode and dates. We will come back with a supply price or an introduction to suppliers who can hold it.