Reinforcement, stabilisation, separation, drainage, filtration and sealing are all roles for geosynthetics in Roads. Nonwovens are used as a filter and drainage medium in road foundation drainage or as a separation layer between the structural layers and the formation or road foundation. High-strength geogrids and wovens reinforce and stabilise the structural layers and provide increased load-bearing capacities.

Asphalt reinforcement grids prevent or delay the onset of reflective cracking in road surfaces (see animation). These cracks are often caused by temperature variations and traffic loading. Areas typically prone to this type of cracking include longitudinal joints in widened roads, asphalt surfacing over old concrete road slabs (expansion joints) and distressed blacktop construction.