What methods are commonly used for waterproofing GRC curtain walls?

The core waterproofing treatment of GRC curtain walls adopts a three-in-one solution of "joint sealing waterproofing + panel waterproof protection + specialized node waterproofing". Drawing on 28 years of waterproofing experience, Qinglong has optimized waterproofing techniques and material selection, achieving a 100% waterproofing pass rate across multiple outdoor GRC projects with no leakage risks.

I. Joint Sealing Waterproofing: The Core Line of Defense

Joints are the main channels for rainwater penetration, making sealing treatment critical. Sealant selection: neutral weather-resistant silicone sealant or polyurethane sealant is preferred, offering UV resistance, anti-aging properties, and a service life of ≥10 years. Qinglong uses high-end sealants compliant with the GB/T 14683 standard, with tensile adhesion strength ≥1.5MPa. Construction technique: joints must be reserved at a width of 8-12mm; after thorough cleaning, a foam backer rod (with a diameter 20% larger than the joint width) is inserted, then sealant is applied in an arc shape with uniform thickness. Qinglong uses a specialized caulking gun during construction, achieving joint flatness ≤1mm with no bubbles or cracks. Expansion joint treatment: large double-curved curtain walls require expansion joints (spaced 20-30m apart), combining elastic sealing materials with metal cover plates. Qinglong's expansion joint design accommodates ±20mm of deformation, balancing waterproofing and deformation compensation.

II. Panel Waterproof Protection: Enhancing Intrinsic Waterproofing Capability

Intrinsic panel waterproofing reduces the risk of rainwater penetration. Surface treatment: outdoor GRC panel surfaces are coated with waterproof coatings (such as fluorocarbon paint or silane impregnation agents) to form a waterproof protective film. Qinglong uses a two-primer + two-topcoat process with a coating thickness ≥150μm, reducing water absorption by 60%. Panel quality control: production ensures panel density ≥2.2g/cm³, free from defects such as honeycombs, pitted surfaces, and cracks. Qinglong panels undergo impermeability testing before leaving the factory, with impermeability grade ≥P12. Edge treatment: panel edges and corners are chamfered (R≥5mm) to prevent sharp edges from cutting the sealant. Qinglong's panel chamfering precision is ≤±0.5mm, with smooth edges free of burrs.

III. Specialized Node Waterproofing: Eliminating Hidden Risks

Nodes such as hanging fixtures, embedded parts, and corners are weak points in waterproofing. Hanging fixture nodes: waterproof gaskets (such as butyl rubber pads) are installed at the connection between hanging fixtures and panels to prevent rainwater from seeping through gaps. Qinglong's waterproof gaskets have a thickness ≥5mm and a compression deformation rate ≤10%. Embedded part nodes: the area around embedded parts is filled with sealant and waterproof mortar, with metal cover plates installed on the outside for protection. Qinglong's embedded part waterproofing adopts a triple protection of "sealant + waterproof mortar + cover plate" with no water leakage risks. Corner nodes: specialized corner seals are used at internal and external corners, with sealant applied in continuous arcs. Qinglong's corner node waterproofing is verified through water spray testing, with a pass requiring 30 minutes of continuous spraying without leakage.