As for the choice of the type of gravel, there are four parameters to take into account:


We advise against choosing gravel types with a minimum grain size smaller than 4 mm. Finer grain sizes could get stuck in shoes or wedge themselves between car tire treads. In order to optimally pack the honeycombs, we advise that you limit the maximum diameter of the gravel to 16 mm.

Recommended for applications without cars: 4-8 mm. Recommended for applications with cars: 8-16 mm.


When we speak of round gravel types, we mean pebble. When we talk about broken gravel types we mean gravel. Pebble is nicer for terraces and garden paths, whereas gravel has the advantage that the top layer (this is the layer on top of the honeycomb structure to make the structure invisible) is less likely to shift. Gravel is therefore preferred in places where vehicles will be driving over the surface.


Hard gravel types are less likely to crumble under moving loads and are less quick to turn green as they retain less water (lower porosity). A soft rock – with a high porosity – on the other hand crumbles easily and dissolves over time. Consequently, soft rock will become water permeable in the long term, leading to puddles and rutting. Moreover, it will turn green on non-sunny sides. Lastly, gravel made from soft rock will produce dust in the summer and stick to one’s shoes in the winter.


Gravel or pebbles are a natural stone and will retain their colour, even after a long time. For lighter gravel or pebble types the best choice is a white ECCOgravel grid, while for darker gravel or pebble types one would sooner use a black ECCOgravel grid.