How to Handle GRC Exterior Wall Joint Leakage? Repair and Prevention Solutions

Addressing joint leakage in GRC exterior walls requires following the principle of "identifying root causes → precise repair → long-term prevention". Core repair methods include sealant replacement, joint reinforcement, and drainage optimization. With 28 years of waterproofing experience, Qinglong has achieved a leakage repair success rate of 99.5%. Projects such as Guangzhou Dongzhu Shangdu and Sanya Yingbin Yihao have completely resolved leakage issues.

I. Precise Investigation of Leakage Root Causes

Identifying the root cause is the prerequisite for repair. Common causes: sealant aging and cracking, insufficiently reserved panel joints, blocked drainage holes, and gaps caused by installation deviation. Qinglong adopts "visual inspection + tapping method + water spray test" with a 100% hazard identification rate. Key inspection areas: around door and window openings, internal and external corners, expansion joints, and fixing connection points—these are high-risk leakage areas, and Qinglong achieves 100% inspection coverage for key projects. Tool assistance: infrared thermal imaging cameras are used to detect hidden leakage. Qinglong's infrared detection can identify internal moisture accumulation, avoiding blind repairs.

II. Precise Repair Solutions and Construction Standards

Targeted repairs resolve leakage problems. Sealant replacement: remove aged sealant, clean the joints, and fill with foam backer rods plus neutral-cure weather-resistant sealant (elongation ≥500%). Qinglong sealant has a bond strength ≥1.0MPa and excellent anti-aging performance. Joint reinforcement: when gaps are too large, install stainless steel pressure strips plus sealant for double protection. Qinglong pressure strips are ≥2mm thick to enhance sealing. Drainage optimization: unclog or add drainage holes (8-10mm diameter, spacing ≤1m). Qinglong drainage holes feature an anti-clogging design to prevent debris blockage. Substrate treatment: if the substrate leaks water, apply waterproof coating plus waterproof membrane. Qinglong waterproof coating has an impermeability grade ≥P8 and good compatibility with GRC. Construction standards: after repair, conduct a water spray test—no leakage for 30 consecutive minutes counts as passing. Qinglong's repair acceptance pass rate is 100%.

III. Long-Term Preventive Measures and Qinglong Project Practice

Prevention first reduces leakage recurrence. Design optimization: reserve 8-12mm panel joints and use tongue-and-groove joints plus drainage channels. Qinglong uses BIM modeling to optimize joint design, reducing leakage risk by 60%. Material upgrades: select highly weather-resistant sealant (fluorocarbon sealant). Qinglong sealant has a service life of over 10 years. Installation standards: control installation deviation ≤2mm to ensure uniform panel joints. Qinglong uses laser-positioned installation with a deviation rate ≤0.5%. Regular maintenance: inspect sealant and drainage holes annually and clear blockages promptly. Qinglong's maintenance team responds within 48 hours. Project cases: Guangzhou Dongzhu Shangdu Commercial City had joint leakage at multi-point hanging connections of GRC cladding panels. Through "sealant replacement + new drainage holes + pressure strip reinforcement", Qinglong repaired it with no leakage over 5 years of use. Sanya Yingbin Yihao coastal project: joint leakage was repaired by Qinglong with annual protection, withstanding typhoons and rainstorms without abnormalities.