How to Clean a Dirty GRC Surface?

GRC components inevitably accumulate dirt during use, and scientific cleaning methods not only restore their appearance but also extend their service life. Based on years of project experience, Qinglong Group has refined GRC cleaning work into three major steps—pollutant analysis, cleaning agent selection, and process control—to ensure that cleaning is safe and effective.

Pollutant diagnosis before cleaning is the primary step. Common GRC stains include dust buildup, rust, algae growth, and industrial pollutants. In the Shanghai Qingpu R&D Base project undertaken by Qinglong, we formulated a targeted plan only after determining the composition of the pollutants through laboratory analysis. For ordinary dust, rinsing with clean water at a pressure not exceeding 50Bar is sufficient; for stubborn stains, specialized cleaning agents may be required. It should be noted that different surface treatment processes (such as stone-imitation textures and smooth surfaces) vary in their tolerance to cleaning methods.

The choice of cleaning agent directly affects GRC surface protection. Strongly acidic (pH<3) or strongly alkaline (pH>11) cleaning agents are strictly prohibited, as they corrode the protective layer on the GRC surface. Qinglong recommends using neutral cleaning agents together with soft-bristle brushes. In the Shenzhen Yirui Biotechnology Building project, we adopted biodegradable cleaning agents, which ensured cleaning effectiveness while meeting environmental requirements. For colored GRC components, a small-area test should be carried out in an inconspicuous spot before use to ensure that no fading occurs.

Control of the cleaning process is equally important. Cleaning is recommended on cloudy days or in the early morning and evening, to avoid excessive surface temperatures causing the cleaning agent to evaporate too quickly. When rinsing, keep the nozzle at a 45-degree angle to the GRC surface at a distance of 30-50 cm, working from top to bottom. In the cleaning of the Hainan Changying Paradise project, Qinglong also paid special attention to the treatment of joints to prevent moisture from penetrating the insulation layer. After cleaning, rinse thoroughly with clean water promptly to prevent cleaning agent residue.

Special stains require targeted treatment. Emulsifying cleaning agents can be used for oil stains; specialized rust removers for rust; and mold-inhibiting additives may be considered for areas with algae growth. Qinglong recommends 1-2 professional cleanings per year, along with establishing a cleaning log that records the time of each cleaning, the cleaning agents used, and an effectiveness evaluation, providing a basis for subsequent maintenance.