What Methods Are Typically Used for GRC Curtain Wall Waterproofing? Technical Analysis of the Qinglong GRC Waterproofing System

Waterproofing treatment of GRC curtain walls is key to ensuring building functionality, requiring a systematic waterproofing concept of "prioritizing drainage with combined prevention and drainage." Based on 28 years of waterproofing technology practice, Qinglong GRC has developed a complete waterproofing solution.

In a seaside super high-rise project in Xiamen, Qinglong GRC adopted a three-level waterproofing system: the first level is weather-resistant sealant at panel joints (movement capability ±25%), the second level is a cavity drainage system, and the third level is an inner waterproof sealing layer. Particularly in typhoon-prone areas, a pressure-balanced design was adopted, with no leakage under a 2000Pa wind pressure test. The project has withstood multiple typhoons, with interior spaces remaining dry, demonstrating the remarkable effectiveness of the waterproofing system.

Panel Joint Waterproofing System Design

EPDM rubber strips are used as backing material, with sealant thickness at 1/2 of the joint width and no less than 6mm. The bonding length between sealant and GRC is ≥ the joint width, and two-component sealant is used to ensure deep curing. This design ensures a 50-year service life.

Cavity Drainage System Construction

A 20mm thick cavity is provided with drainage holes at the bottom (spacing ≤1m). Water guide plates are installed inside the cavity to direct infiltrated water toward the drainage holes. The drainage holes are fitted with insect screens with 3mm apertures. This system can effectively drain infiltrated water.

Waterproofing Reinforcement at Special Locations

Drip edges are set at horizontal joints with an overhang ≥20mm; internal and external corners are reinforced with sealing using special corner sealant; waterproof sleeves are installed around wall-penetrating pipes and sealed with sealant. These locations require special attention.

Material Selection and Construction Control

Silicone or modified silicone sealants are selected with movement capability ≥25%; application temperature is 5-40℃ with humidity 40%-80%; bonding surface cleanliness must meet standard requirements, and sealant application should be continuous and uniform. These controls ensure construction quality.

Waterproofing systems require professional design and construction. It is recommended to select quality materials and construct strictly according to specifications. Qinglong GRC provides complete waterproofing solutions to ensure curtain wall functionality.