The life of surface dressing can be enhanced still further using a non-woven geosynthetic interlayer which is laid on the road surface ahead of the surface dressing process, forming retention and regulating layer for the bitumen and allowing embedment of the chip with good adhesion.

Tests have shown that the life of the treatment can be extended by 2-3 times due to the Stress Absorbing Membrane Interlayer (SAMI) which intercepts a reflective crack as it passes up through the lower layers preventing it propagating up to the surface. These cracks would otherwise allow water ingress and rapid deterioration of the surface.