What Is the Impermeability Testing Method for GRC Exterior Walls? Anti-Seepage Barrier and Qinglong Group Quality Verification System

Water impermeability testing of GRC exterior walls is a core means of evaluating their durability and waterproofing grade, verified mainly through three methods: "laboratory standard testing, on-site simulation testing, and long-term performance monitoring." Qinglong Group has established a complete testing system based on the national standard "Test Methods for Glass Fibre Reinforced Cement" (JC/T 2547): in the laboratory, the impermeability grade method (step-by-step pressurization to a specified value, such as P6 or P8) and the water penetration height method are used; on-site, water spray tests are employed (nozzle 0.5 m from the wall, water pressure 0.2 MPa, lasting 2 hours); and long-term performance changes are monitored with thickness gauges and hygrometers. During the acceptance inspection of the Nanning Wuxiang China Resources MixC One project, we sampled 30 panels for on-site water spray testing; not a single rear face showed any leakage, and all panels achieved an impermeability grade of P8 or above. Scientific testing is a reliable endorsement of GRC's waterproofing promise.

Laboratory Standard Testing Is the Basis for Performance Grading

Standard specimens are prepared (e.g., prisms of 175 mm × 185 mm × 150 mm) and pressurized on a dedicated impermeability apparatus starting from 0.1 MPa, increasing by 0.1 MPa every 8 hours, until seepage occurs in one of the specimens, or the specified pressure (e.g., 0.8 MPa) is reached and maintained for 24 hours without leakage, whereupon the corresponding grade (e.g., P8) is assigned. This method is accurate and reliable, and is used for material certification and mix proportion optimization.

On-Site Simulation Testing Is Key to Project Acceptance

In accordance with the "Technical Specification for Waterproofing Engineering of Building Exterior Walls" (JGJ/T 235), water spray tests are carried out on installed curtain walls. The wall surface is divided into inspection lots, with at least one location selected from each lot for continuous spraying by a dedicated spray system. We use automatic rotating spray heads to ensure uniform coverage, with spraying time, water pressure, and distance strictly in accordance with the standard.

Non-Destructive Testing and Long-Term Monitoring Safeguard Quality Traceability

An infrared thermal imager is used to scan the wall surface, identifying cold spots that may indicate leakage through temperature differences; a hygrometer is used to detect changes in the moisture content of the base wall. For key projects, we embed humidity sensors to monitor the humidity inside the cavity over the long term, with data transmitted wirelessly to a management platform, enabling predictive maintenance.

Qinglong Group's Full-Process Impermeability Control

From raw materials (controlling chloride ion content ≤ 0.02%), mix proportions (water-binder ratio ≤ 0.38), and production (vibration compaction) to installation (joint treatment), impermeability is controlled throughout the entire process. Each batch of products is spot-checked before leaving the factory, and a test report is issued.

Impermeability testing is not an after-the-fact remedy but a quality assurance measure that runs throughout. Qinglong Group lets the data speak, ensuring that every square meter of GRC curtain wall can withstand the test of wind and rain.