Gezhouba School Exterior Wall

Background

Project Background: This project involved the exterior wall renovation of Gezhouba School in Yichang, Hubei, covering over tens of thousands of square meters across 12 buildings including teaching and dormitory blocks. The region has a subtropical monsoon climate with high temperature and humidity in summer, frequent rainfall, and occasional freeze-thaw cycles in winter. Traditional coatings often suffer from powdering, cracking, and mildew under such conditions, failing to meet the dual requirements of durability and aesthetics for campus buildings. Technical Solution: Exterior multicolor paint was selected as the topcoat, paired with an alkali & mould resistant primer to form a protective barrier, followed by Odorless All-Effect 5-in-1 paint to enhance decorative and functional properties. The alkali & mould resistant primer effectively blocks the penetration of alkaline substances from the wall, with adhesion ≥ grade 1; the multicolor topcoat uses elastic acrylic resin as the binder, offering excellent elastic crack resistance to cover fine cracks ≤2mm. The topcoat has a hiding power ≥98%, and its VOC content ≤30g/L, meeting green building material standards. Construction Process: Before application, loose layers and dust on the substrate must be completely removed. The alkali & mould resistant primer can be applied only when the substrate moisture content is ≤8%, with a coverage rate of 8-10㎡/kg, requiring 2 coats to ensure full sealing. After the primer dries completely, one coat of multicolor paint is applied first, followed by 2 coats of Odorless All-Effect 5-in-1 paint. The film thickness per coat is controlled at 25-30μm, with a total dry film thickness ≥80μm. The construction environment must maintain a temperature of 5-35℃ and relative humidity ≤85%. Project Results: Tests show that the coating adhesion is ≥ grade 1, scrub resistance ≥2000 times, artificial aging resistance ≥1000 hours, and the waterproof grade reaches P10 level as specified in GB/T 50208, fully meeting the long-term use requirements of campus buildings. The project passed acceptance on the first attempt. The school authorities commented that the coating features uniform color and rich texture, with no peculiar smell during construction, causing no disruption to normal teaching activities. A 5-year warranty service is provided thereafter.