Permalayer is an anti-fracture underlay designed for use over timber as well as green and cured concrete slabs and screeds. The unique Permalayer system enables fractures up to 3mm wide to be bridged without affecting the tiled finish. When used correctly Permalayer removes the need for costly floor build-ups such as plywood overlays. The layer enables the substrate beneath to move laterally, protecting the tiled finish from the detrimental effects of subfloor movement. A solid bed can also be achieved due to the flat nature of the underlay eliminating the problems associated with point loading.