# Ballast, crushed stone or crushed concrete: what to put under a path

Published: 2026-09-16

**In short:** Ballast is the natural mix of sand and gravel and is used as a base layer. Crushed stone has edges that lock together, so it has better load-bearing capacity, and it goes on top. Crushed concrete is recycled material, cheaper, and suitable for fills and platforms with light traffic.

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The question comes up with every path, platform or yard. The short answer: the material matters less than the layer thickness and the compaction. But each material has its place.

## Ballast

A natural mix of sand and gravel, extracted from riverbeds. It spreads easily, it is cheap and it makes a good base layer, because it settles evenly.

**Used for:** the foundation layer, fills, raising the ground level.

**Its limitation:** it has rounded grains, which can move against each other. That is why it is not left as the final layer under heavy traffic.

## Crushed stone

Crushed rock with sharp edges. The edges lock into each other during compaction and form a much more stable layer than ballast.

**Used for:** the top layer of the foundation, directly under asphalt or block paving, and for platforms that carry traffic.

**It costs more** than ballast, but the difference is justified exactly where the loads occur.

## Crushed concrete

Old concrete from demolitions, crushed and sorted. It is recycled material, so the cheapest of the three, and it has edges, like crushed stone.

**Used for:** fills, temporary site roads, platforms with light traffic, layers under foundations.

**Watch the quality:** it must be clean, sorted and free of leftover reinforcement or brick. Poorly sorted crushed concrete causes settlement.

## How thick it needs to be

There is no universal number — it depends on the ground underneath and on what will travel on top. The rule of thumb:

- **footpath or path for small cars:** a thinner layer, a single compacted layer
- **yard with ordinary vehicle access:** two layers, compacted separately
- **platform with trucks:** a thick layer, laid in several passes, with crushed stone on top

The ground underneath decides. On clayey soil that holds water, you need more than on stony, free-draining ground.

## The part most often done wrong

**Compaction in layers.** If you lay 30 centimetres at once and go over it with the roller, you compact only the top few centimetres. Underneath, loose material remains, which will settle in the first year and leave bumps.

The right way is to lay the material in layers and compact each layer separately before putting down the next. It takes longer, but it is the only method that lasts.

**The second mistake:** the topsoil is not stripped. Soil with roots and organic matter rots and settles, whatever you put on top.

## Which machines are used

For spreading and levelling: a bulldozer or a motor grader. For compaction: a compactor roller on large areas, a plate compactor in narrow areas and next to kerbs. For transport: dump trucks.

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## Contact

Phone: +40 729 553 449
Contact form: https://inchiriez-utilaje.ro/en/contact/
Article: https://inchiriez-utilaje.ro/en/blog/ballast-crushed-stone-or-crushed-concrete-under-a-path/
Romanian version: https://inchiriez-utilaje.ro/blog/ce-se-pune-sub-o-alee/