How to Deal with Joint Leakage in GRC Exterior Walls? Leakage Treatment and Qinglong Group's Systematic Waterproofing Solution

GRC exterior wall joint leakage is a common quality defect. Its treatment must follow the principle of “accurate cause identification, thorough treatment, and prevention first”, adopting a four-step approach of “grouting and sealing, sealant renewal, structural improvement, and systematic maintenance”. From 28 years of maintenance practice, Qinglong Group has developed a standard leakage treatment procedure: first locate leakage points through water spray tests and endoscopic inspection; apply low-pressure grouting (epoxy resin) to active cracks; remove failed sealant and re-apply high-elasticity silicone sealant (movement capability ≥25%); add drainage holes or improve joint construction where necessary; and finally strengthen regular inspections. In a leakage repair for a commercial complex project in Nanning, we permanently resolved the leakage problem that had troubled the owner for years through grouting plus sealant system renewal, with no recurrence in five years. Joints are the key to waterproofing and must be treated for both symptoms and root causes.

Accurate Diagnosis Is the Prerequisite for Successful Treatment

Leakage causes are varied: sealant aging and cracking, damaged backer rods, excessive joint deformation caused by installation errors, improper drainage design, and so on. A comprehensive analysis through on-site observation and instrument testing (such as moisture meters and infrared thermography) is required. We have established a leakage cause diagnosis tree to improve treatment precision.

Material and Process Selection Determine Treatment Results

For crack leakage, use low-viscosity epoxy grout with pressure controlled at 0.2-0.5 MPa and inject slowly. For failed sealant joints, the old sealant must be thoroughly removed (with the depth-to-width ratio still at 1:2 or 2:1), the substrate treated with a special cleaner, and the new sealant applied fully and continuously. We use well-known brand silicone sealants and provide a 10-year warranty.

Structural Improvement Is the Foundation of Long-Term Waterproofing

For design defects (such as joints that are too narrow or lack drainage channels), structural optimization is required, such as adding drip edges, converting flat joints to tongue-and-groove joints, and installing drainage holes at the bottom of the cavity behind panels. Qinglong Group fully considers waterproofing construction details at the detailed design stage, avoiding problems at the source.

Preventive Maintenance Is Better Than Remedial Repair

Establish a regular joint inspection system (recommended annually), focusing on sealant elasticity and adhesion, and replace sealant promptly when signs of aging are found. We provide customers with joint maintenance guides and regular inspection services to prevent problems before they occur.

Joint leakage treatment requires professional judgment and meticulous work. With extensive treatment experience, Qinglong Group provides customers with once-and-for-all solutions.