Technical Mortars and Tile Adhesives: Bonding, Grouting, and Repairing with Sika
Quick answer: bonding tile, grouting it, and repairing concrete are three different jobs, each needing a specific mortar. Sika has a product certified to the relevant European standard for each: tile adhesive for bonding, grout to fill the joint between pieces, structural repair mortar to restore damaged concrete, and a polyurethane sealant for the assembly's expansion joints.
Underfloor heating, façades, terraces, and pools, where the substrate moves and a conventional C1 would cause the tile to come loose
Grout: Filling the Joint Between Tiles
SikaCeram®-650 Classic is a CG2WA grout (EN 13888 standard) for joints from 1 to 6 mm, water-repellent (resists water and dirt) and highly abrasion-resistant. Its 24-color range is key: the joint accounts for up to 10% of a tiled surface's visible area, so the tone you choose makes the difference between a job that looks correct and one that looks like it's straight out of a catalog.
Structural Concrete Repair
SikaEmaco®-2480 is a self-leveling structural repair mortar classified R4 (the most demanding category under EN 1504-3), with 55 MPa compressive strength. Its fluidity allows it to be poured or pumped into formwork and fill build-ups of up to 150 mm in a single layer, without working in lifts as a conventional thixotropic mortar would require.
Sealing the Expansion Joints
Once the tile is laid and grouted, the assembly's expansion joints are sealed with Sikaflex®-11 FC Purform®, a polyurethane sealant-adhesive with ±25% movement capacity and 800% elongation at break, which absorbs expansion and vibration without cracking.
Work Order for a Tiling Job
Repair the base concrete if damaged, with SikaEmaco-2480 if the defect is structural.
Bond the tile with the adhesive suited to the substrate: Sika LANKO Flexible if there's movement (underfloor heating, exterior) or Sika MiniPack for a standard small renovation.
Grout with SikaCeram-650 Classic, choosing the color from the range that best matches the tile.
Seal the perimeter and junction expansion joints with Sikaflex-11 FC Purform.
Frequently Asked Questions
What's the difference between a C2TE and a C2TES1 tile adhesive?
The S1 indicates the adhesive is deformable: it absorbs movement in the substrate, essential for underfloor heating, façades, or pools. A conventional C2TE is suitable for standard floors and walls without that movement.
Can I use silicone instead of Sikaflex for the tiling's expansion joints?
A polyurethane sealant like Sikaflex-11 FC offers greater movement capacity and structural adhesion than conventional silicone, and can often be painted too; check the technical data sheet for your material.
When do I need an R4 mortar instead of a conventional repair mortar?
When the damage affects the element's structural capacity (columns, beams, slabs with exposed rebar) and you need strength certified to EN 1504-3; for superficial cosmetic repairs, a lower-class mortar is usually enough.
