Crack Repairs and Underpinning of Curling Slabs

Not all cracks are the same, and treating them all the same way is how repairs fail. Before selecting a material or method, the cause, extent and width of the crack need to be established, since that's what actually determines the right fix.

Matching the repair to the crack

Fine map-cracking, which isn't structural and usually only shows when the surface is wet, can be treated with MM Sealer Siloxane to improve aesthetics and prevent water ingress.

Cracks in horizontal slabs call for a different approach, depending on width:

• LVE Repair (low viscosity or gel epoxy), or Graviject T: pack size 1L kit, yield dependent on site requirements.
• SFCF Grout (SuperFineCrackFiller): a cementitious, polymer-modified, pumpable and injectable slurry with unique crack-filling capability, suitable for cracks wider than 2mm. Pack size 20kg, yield 1L per 3kg (2L slurry), water 30–35% by mass (6–7L per 20kg), applied by caulking gun.

Getting it right the first time

For technical data sheets and installation processes, request a Samson method statement for site instruction before you start, since crack repair is one of those jobs where the wrong product choice, or the wrong prep, means doing it twice.

Browse our repairs & water repellency range or request on-site technical advice if you're not sure which product fits your crack.