Sand or gravel — which should you choose?
The choice between sand and gravel depends on what the material has to do. Particle size is important, but the name alone does not confirm permeability, compactability or suitability for your project. You need the right specification before you buy.
Particle size and composition
Sand has finer particles than gravel. In a specific material, however, you need to check the whole grading and the content of fines. Two aggregates both called gravel can behave differently in contact with water.
Do not judge suitability only by how the material looks in the yard. Cleanliness, particle shape and size distribution can also matter.
When is the name alone not enough?
For a structural layer, the design requirements and the construction method are what count. A material for draining water may have different requirements from a load-bearing layer. Backfill around foundations also has to take into account the water conditions and the design of the building.
Sand-gravel mix and sub-base mixes are not simply a worse or cheaper substitute for sand or gravel. Their composition may suit a different function. Base your choice on the requirements, not only on the price.
Block paving and drainage
For block paving, distinguish between the sub-base and the bedding layer. We cover aggregate under block paving in more detail in a separate article. For drainage, check the material specified for the particular solution, including the cleanliness requirements. Gravel for drainage.
What to tell us when you order
Give the intended use, the required designation and the quantity you need. If you do not know the specification, agree it with your contractor before you buy. We sell materials by the tonne; converting from volume requires data for the specific aggregate.
Questions about sand and gravel
Which lets water through better?
You have to compare the specific materials, including their fines. The name alone is not enough.
What should I use to backfill foundations?
A material that matches the design solution and the conditions on the plot. There is no single answer for every building.
When should I use sand-gravel mix instead of sand?
When its properties meet the requirements of the layer in question. The suitability of the specific material has to be confirmed.