The weather resistance of waterproof mortar is crucial
The weather resistance of waterproof mortar
The weather resistance of waterproof mortar is a critical performance indicator in practical applications. Enhancing this resistance helps the mortar withstand climate erosion, extend building service life, improve reliability and durability in complex environments, and reduce long-term maintenance costs.
To improve the weather resistance of waterproof mortar, we offer the following recommendations:
- Choose high-quality inorganic binding materials. We recommend Portland cement with a strength grade of 42.5 or higher. For mortar used on the backwater side, use cement with a strength grade of 52.5 or higher.
- Use high-quality sand, such as quartz sand or yellow sand. These types provide better strength and weathering resistance.
- Incorporate weather-resistant polysiloxane-based water-repellent agents. These perform more durably than products based on calcium stearate or sodium/potassium methyl silicate.
- Apply cellulose ethers with a high substitution degree and good water retention. Keep the addition rate below 1‰. Although cellulose ethers are hydrophilic, adding too much can cause the dried mortar film to redissolve in water, weakening waterproof performance.
- Select high-temperature resistant dry powder defoamers. Some defoamers lose effectiveness at high temperatures, affecting mortar density.
Additionally, use a high-quality polycarboxylic superplasticizer. It reduces water content, optimizes pore structure, and increases density—further enhancing long-term weather resistance and durability.
Construction Tips
Pay close attention to construction techniques. Apply proper curing methods and maintain suitable thickness to prevent early water loss or shrinkage cracks. Combining optimal material selection, mix design, and construction control will maximize weather resistance and ensure long-term protection under diverse climatic conditions.
