13. Tile renovation, decorative joints and specialist applications
1. Keeping existing tiles requires a sound substrate
Before coating old tiles, check their bond, hollow areas, wax, oil and cleaning residues. A new coating can fail together with loose tiles even if it adheres strongly to their faces.
Wetting and adhesion on tile differ from ordinary concrete. Follow the product’s preparation requirements, select a compatible primer and verify a small trial. For clear renovation, sanding, local repairs and primer can change the original optical effect. Establish what the process can achieve before promising an unchanged appearance.
2. Renovation without demolition cannot solve every leak
A surface coating may not resolve leaks from supply pipes, drain connections or other areas within walls. Where water has already entered the substrate, assess how trapped moisture can escape after sealing. Diagnose the problem, establish what can be retained, address details and then select the surface system.
Kitchen and bathroom floors also require correct falls, drain connections, threshold heights and wet slip resistance. Retaining tiles does not remove those requirements. Suitability depends on site conditions, not only the wish to avoid demolition.
3. Decorative grouting does not replace complete waterproofing
Polyaspartic technology can be used in certain joint and decorative materials, but grout serves a different function from a continuous waterproofing membrane. Joint width and depth, adjacent materials, movement and cleaning all matter. A closed-looking joint does not prove that a reliable waterproofing construction exists beneath it.
Exterior joints also experience sunlight and temperature changes. Confirm whether the grade supports exposure and moving joints, and when water contact is allowed. Ordinary decorative joints and structural movement joints need separate designs.
4. Timber, composites and specialist facilities need specific validation
Timber changes dimensions with humidity; composites may retain mold-release agents; plastics vary in surface energy and solvent resistance. Check compatibility, adhesion and movement on these substrates instead of directly transferring steel or concrete experience.
Drinking-water contact, direct food contact, continuous pool immersion, electrical insulation, flame retardancy and antistatic service require application-specific evidence. Use within a building does not automatically give a coating every certification or function that the building may require.