Ceresit CT190 MW FLEX - Wool & Mesh Adhesive - 25kg
What is Ceresit CT 190?
Ceresit CT 190 is a high-performance Universal Adhesive and Basecoat specifically designed for Mineral Wool (Rockwool) insulation systems. It is a dual-purpose mortar used to both bond insulation boards to the substrate and create a fiber-reinforced basecoat layer with mesh. It is highly breathable, fire-resistant, and essential for "breathable" facade systems.
| Technical Specification | Value / Detail |
|---|---|
| Material Base | Cement-based with synthetic resins and micro-fibers |
| Primary Use | Fixing & Basecoating Mineral Wool (Rockwool) |
| Consumption (Fixing) | Approx. 5.0 kg/m² |
| Consumption (Basecoat) | Approx. 5.0 kg/m² |
| Reinforcement | Micro-fiber reinforced for crack resistance |
| Vapour Permeability | Very High (V1 rating) |
| Adhesion to Wool | > 0.015 MPa (higher than wool strength) |
- Can Ceresit CT 190 be used for both EPS and Mineral Wool?
Yes. CT 190 is a "Universal" mortar. While it is specially optimized with high adhesion for the fibrous surface of Mineral Wool, it can also be used for EPS (Polystyrene). However, for standard EPS projects, many installers use Ceresit CT 85 to optimize costs. - Why is CT 190 required for Mineral Wool systems?
Mineral Wool systems require high vapour permeability (breathability). CT 190 is engineered to allow moisture to pass through the wall while remaining waterproof from the outside. Its micro-fiber reinforcement handles the higher thermal movement common in Mineral Wool systems. - How many bags of CT 190 do I need per square meter?
For a complete system (Fixing + Basecoating), you typically need 10kg per m², which equates to one 25kg bag for every 2.5m² of wall area.
- Mixing: Mix one 25kg bag with approx. 6.5L of clean water. Wait 5 minutes and re-mix.
- "Scratch Coat" (Important): For Mineral Wool, apply a very thin layer of CT 190 to the back of the board first to flatten the fibers.
- Fixing: Apply the "perimeter and dab" method over the scratch coat and press the board to the wall.
- Basecoating: Once the boards are pinned, apply a 3–4mm layer of CT 190.
- Mesh Embedding: Lay the Fiberglass Mesh into the wet mortar and smooth over.
- Pro-Tip on Safety: Mineral Wool systems are often chosen for their non-combustible properties. Using CT 190 ensures the entire system maintains its fire rating as it is a cement-based mineral product.
- Pro-Tip for Summer: Because CT 190 contains cement, it must not dry too quickly in direct sun. Use scaffolding nets to shade the wall, otherwise, the basecoat may "burn" and lose its strength.