Is GRC's Waterproofing Performance Good? An Analysis of the Relationship Between Water Resistance and Engineering Waterproofing Design

It is necessary to clearly distinguish between the two concepts of "waterproofing" and "water resistance". GRC itself is not an absolutely waterproof (impermeable) material like metal or glass; it is a porous material with a microporous structure and a certain water absorption rate (quality products are usually below 10%). However, GRC has excellent "water resistance", meaning that its physical and mechanical properties remain stable under long-term damp or wet-dry cycling conditions, and it is not prone to severe strength loss, dissolution, or drastic volume deformation caused by the action of water. Qinglong Group adopts low water-cement ratio formulations and incorporates active micro-powders such as silica fume together with polymer emulsions to achieve a highly densified matrix structure, significantly reducing its water absorption rate and moisture permeability, thereby enhancing its long-term resistance to water erosion.

In construction projects, the "waterproofing" function of GRC components (especially exterior wall cladding panels) does not rely on the material itself to achieve absolute impermeability, but is realized through scientific system design. This includes: the GRC panel itself serving as a weather-resistant, water-resistant protective layer; the joints between panels being flexibly sealed with highly elastic, aging-resistant sealant to form a second line of waterproofing; and most importantly, in GRC curtain wall system design, the principle of "drainage, pressure equalization, and combined waterproofing and drainage" is widely adopted, i.e., cavities are designed behind the panels with water-guide plates and drainage holes, so that even if a small amount of moisture penetrates into the joints or the material interior, it can drain smoothly to the outside through the cavity, preventing accumulation inside the wall. While providing GRC products, Qinglong Group also offers complete curtain wall system solutions to ensure the watertightness of the entire envelope system is absolutely reliable.

Therefore, to judge whether the "waterproofing performance" of GRC used on exterior walls is good, the key lies in assessing its long-term weather resistance as a component of the exterior wall system and the overall waterproofing reliability of the system. Quality GRC panels feature low water absorption, high dimensional stability (small wet-dry deformation), and good freeze-thaw resistance, which ensure that they are not prone to cracking or powdering under rain erosion, sun exposure, and freeze-thaw cycles, providing a stable foundation for the entire system. In actual projects, as long as the system design is sound, the installation is standardized, and the sealing is properly done, GRC curtain walls can fully meet the highest-grade exterior wall waterproofing requirements. Qinglong Group's numerous successful cases across the country, from the rainy south to the severely cold north, are the most powerful proof of the outstanding water resistance and weather resistance of its GRC products and systems.