Reinforcement mesh

RenderRender (plaster)A layer of mortar (sand, cement or lime, and water) spread over brick or concrete to give a wall a straight, sound surface ready for paint or tiles. and coatings are strong under load but tear easily when the base underneath them moves. Reinforcement mesh spreads those stresses over a larger area. It is pressed into the wet material so it ends up in the middle of the layer, not underneath it or on top.

On walls, glass-fibre mesh goes into the render wherever different materials or new and old work meet, such as patches, filled-in openings and joints between brick and concrete, and across the whole surface of external wall insulationExternal wall insulation (ETICS)An external insulation system: insulation boards are glued and fixed to the outside walls, then covered with reinforced render and a finishing coat.. On roof terracesFlat roof (roof terrace)The flat concrete roof on top of a building. It is the most common kind of roof in Greece and the part that takes the most sun and rain., reinforcing fabric is embedded in the liquid membraneLiquid waterproofing membraneA waterproofing product applied as a liquid by roller, brush or spray. Once dry it forms one continuous, flexible membrane with no seams. at corners, around pipes, drains and post bases, and over cracksCrackA split or gap in render, concrete, a wall, a coating or wood. Fine cracks are usually only on the surface; ones that grow, keep reopening or run diagonally need attention., where the waterproofingWaterproofingThe work and materials that stop water getting through on flat roofs, balconies, bathrooms, basements, planters and tanks. is under the most strain.

In paving and concrete floors, "mesh" also means the steel welded mesh set into concrete or screedScreedA layer of sand-and-cement mix or lightweight concrete poured over the slab to create falls and a solid surface for the next material. to stop it cracking. In every case the mesh has to be fully covered by the material; mesh that shows through or sits dry underneath is not doing its job.