GRC Exterior Wall Impermeability Testing: Standard Methods and Qinglong Practical Guide

Impermeability is a core functional indicator of GRC exterior walls, directly determining their ability to resist rainwater penetration. As a participant in formulating the Technical Standard for the Application of Glass Fiber Reinforced Cement (GRC) in Buildings, Qinglong Group has established a well-developed impermeability testing system over 28 years, ensuring that every batch of GRC exterior wall panels meets impermeability standards.

Impermeability testing of GRC exterior walls must follow industry standards, with scientific methods used to evaluate the impermeability grade, preventing leakage and substrate aging caused by insufficient impermeability. Qinglong's testing system covers factory testing and on-site testing, forming a dual safeguard.

Core Standards for Impermeability Testing: Clear Safety Thresholds

According to the JGJ/T423-2018 standard, the impermeability grade of GRC exterior wall panels should be no lower than P6 (i.e., able to withstand 0.6MPa of water pressure for 30 minutes without leakage). For coastal and rainy regions, upgrading to P8 is recommended to enhance impermeability. GRC exterior wall panels produced by Qinglong all achieve an impermeability grade of P8 or above, meeting the requirements of demanding environments.

Standardized Testing Process: From Sample Preparation to Result Determination

For sample preparation, 3 panels are randomly selected from each batch of GRC panels and cut into specimens of 150mm×150mm×panel thickness, cured to 28 days. Testing is conducted with a permeameter: the specimen is fixed in place, water pressure is applied gradually starting from 0.2MPa, with each pressure level maintained for 30 minutes until leakage occurs, and the maximum impermeability pressure is recorded. Qinglong has a professional impermeability testing laboratory equipped with high-precision permeameters, keeping testing error within ±0.02MPa. In the Nanning Wuxiang China Resources MixC One project, all GRC exterior wall panels achieved an impermeability grade of P8 through rigorous testing.

On-Site Testing and Qinglong's Control System: Dual Safeguards for Impermeability

On-site testing uses a water spray test: a high-pressure water gun sprays the wall from a distance of 30cm for 30 minutes, and the interior side is then checked for leakage. During the construction acceptance stage, Qinglong conducts comprehensive water spray tests on GRC exterior walls and delivers only after ensuring there is no leakage. In the production process, impermeability is enhanced at the source by optimizing slurry mix ratios, improving density, and strengthening sealing treatment, forming a triple impermeability safeguard of “production control + factory testing + on-site acceptance”.

Impermeability testing of GRC exterior walls is the “touchstone” of engineering quality. For 28 years, Qinglong has consistently adhered to the principle of “standardized testing and source control”, ensuring that GRC exterior walls meet impermeability standards through scientific testing methods and strict quality control. Reliable impermeability effectively resists rainwater penetration, extends the service life of GRC exterior walls, safeguards building safety, and demonstrates Qinglong's professional strength as an industry leader.