Types of Cement-Based Adhesives: Choosing the Right One for Your Project
Cement-based tile adhesives are among the most widely used bonding materials in construction due to their versatility, durability, and cost-effectiveness.
These adhesives are powdered adhesives that are mixed with water or a liquid additive to form a paste, primarily composed of Portland cement, fine sand, and special additives to enhance bonding strength and flexibility.
Cement-based adhesives are classified using European standards (EN 12004), which define their performance characteristics. Here are the key markings:
C1 and C2:
- C1: Standard adhesive with minimum bond strength of 0.5 N/mm². Suitable for basic tile installations.
- C2: Improved adhesive with higher bond strength (≥1.0 N/mm²). Ideal for demanding applications like larger tiles or outdoor installations.
S1 and S2:
- S1: Flexible adhesive with ≥2.5 mm deformation. Recommended for surfaces prone to movement (e.g., underfloor heating).
- S2: Highly flexible with ≥5 mm deformation. Used for large tiles or challenging substrates.
Additional Markings:
- F: Fast-setting adhesive. Not recommended for AMK installation since you need time to smooth out the sheet.
- T: Non-slump adhesive for vertical applications.
- E: Extended open time for spreading adhesive.
Selecting the right adhesive ensures proper bonding
Advantages of Cement-Based adhesives
- High Bond Strength: Provides a robust and durable connection between the tile and substrate.
- Versatility: Compatible with various materials like ceramic, porcelain, and natural stone.
- Water and Heat Resistance: Suitable for wet areas and heated floors with polymer modification.
- Affordability: Cost-effective compared to other adhesive types.
Special Cement-Based Glues for Insulation Materials
Cement-based glues for insulation materials are designed to securely bond insulation boards such as expanded polystyrene (EPS), extruded polystyrene (XPS), and mineral wool to various surfaces. These adhesives feature added polymers and fibers for enhanced adhesion, flexibility, and strength.
For more reliable bonding layers, use the same glue and a reinforcement mesh to create a base layer on top of insulation material before applying AMK.
How to Use Cement-Based Tile Adhesives
1. Mixing
Follow the manufacturer’s instructions for water-to-powder ratio. Mix until a smooth, lump-free paste is achieved. Avoid overmixing to prevent air bubbles.
2. Application
- Apply the adhesive to the substrate using a flat trowel.
- Spread evenly with a notched trowel. For AMK installation use 6 mm notches and keep grooves in one direction to ensure proper bonding.
- Press tiles firmly into place, sliding slightly to remove air pockets.
3. Setting Time and drying time
Allow the adhesive to set for the recommended time before grouting (usually 24 hours).
When installing AMK, you can fill the seams without waiting for the glue to set. Use the same glue but in a thinner consistency to fill the seams.
Wait at least 48 hours before removing the protective film.
Common Mistakes
Incorrect Mixing Ratios: Leads to weak bonding and cracks.
Inadequate Surface Preparation: Dirt or moisture on the surface can reduce adhesion.
Using the Wrong Type: For example, standard adhesives on flexible substrates may cause tiles to detach.
Working under inappropriate conditions: Extreme temperatures, whether hot or cold, negatively impact the adhesive’s drying process and reduce its lifespan. Most adhesives are best used at temperatures between +10 and +35 degrees Celsius. Avoid working under direct sunlight during the hottest part of the day and in windy conditions. For extra protection, consider using shading nets to block sunlight and wind in your working area.
Conclusion
Cement-based tile glues remain a reliable choice for professional and DIY projects, offering excellent performance across a range of applications. Choosing the right type ensures long-lasting results tailored to your project’s needs.
