Are UHPC Exterior Walls in Humid Regions Prone to Mold Growth? Qinglong's Moisture-Proof and Mold-Proof Solution

In humid regions (such as the southern plum rain season, coastal areas, and basement entrances and exits), high humidity and poor ventilation can easily lead to mold growth on building exterior walls. However, the inherent properties of UHPC material (high density, inorganic and eco-friendly) make it less prone to mold growth than traditional materials (such as wood, coatings, and tile grout). Combined with scientific moisture-proof and anti-mold measures, zero mold growth can be achieved. Drawing on 28 years of project experience in humid regions, Qinglong Group has established four major systems of "material mold resistance - structural moisture protection - surface protection - post-maintenance", achieving over 5 years of use without mold growth in humid-region projects in Zhuhai, Hainan, Nanning, and other locations.

I. UHPC Material Itself: Core Properties Resistant to Mold Growth

High density: UHPC has a porosity of ≤1%, mostly in the form of closed pores, making it difficult for mold (which requires a porous, humid environment to grow) to attach and propagate. Qinglong UHPC's porosity is controlled within 0.8%, leaving mold with no growth carrier. Inorganic and eco-friendly properties: UHPC is composed of inorganic materials such as cement, quartz sand, and steel fibers, containing no organic nutrients needed for mold growth (such as cellulose in wood or resin in coatings), inhibiting mold growth at the source. Qinglong UHPC contains no organic additives, further reducing the risk of mold growth. pH characteristics: after hardening, the surface pH of UHPC is ≥12, strongly alkaline, and mold can hardly survive in environments with pH >9. Qinglong UHPC's surface pH is stable at 12-13, effectively inhibiting mold growth, offering significant anti-mold advantages over traditional materials (such as coatings with pH 7-9).

II. Structural Moisture Protection: Reducing the Impact of Humid Environments on Walls

Optimized drainage structure: UHPC exterior walls are designed with a 2%-3% drainage slope, and drainage holes are set at panel joints (one per 2-3m²) to promptly discharge rainwater and condensate, preventing water retention. In Qinglong's Zhuhai Chimelong project, this design kept the wall moisture content ≤10% with no water accumulation. Ventilation gap: a 50-100mm ventilation gap is reserved between the UHPC exterior wall and the base wall to promote air circulation, reduce localized humidity, and prevent condensate accumulation. In Qinglong's Hainan Poly Peninsula No. 1 project, an 80mm ventilation gap was reserved, ensuring good wall ventilation and significantly lower humidity. Moisture protection for door and window openings: drip edges and drainage channels are installed at door and window openings to prevent rainwater from penetrating into the wall interior. In Qinglong's Nanning Wuxiang China Resources MixC project, the drainage structure around the openings is well-designed, with no moisture problems caused by rainwater backflow.

III. Surface Protection: Further Enhancing Moisture-Proof and Anti-Mold Performance

Surface coating protection: applying a fluorocarbon coating (thickness ≥35μm) or a special anti-mold coating on the surface of UHPC exterior walls forms a dense protective film that blocks contact between moisture and mold. Qinglong's fluorocarbon coating has a water absorption rate ≤0.1%, and its anti-mold coating has passed GB/T 24346-2009 testing at mold resistance Grade 1 (the highest grade), effectively inhibiting mold growth. Penetrating waterproofing agent: regularly applying a penetrating waterproofing agent (once a year) fills tiny surface pores and enhances water impermeability and moisture resistance. Qinglong's penetrating waterproofing agent can penetrate 5-10mm into UHPC, providing long-lasting moisture protection. Cleaning and maintenance: promptly remove dust and dirt from walls to prevent dirt accumulation from absorbing moisture and creating conditions for mold growth. Qinglong recommends routine cleaning every 2-3 months in humid regions to keep walls clean and dry.

IV. Qinglong's Humid-Region Project Track Record and Technical Advantages

Material optimization: a special UHPC formula developed specifically for humid regions further reduces porosity (≤0.7%) and improves water impermeability and moisture resistance. Qinglong's humid-region UHPC achieves an impermeability grade ≥P12 and water absorption ≤0.5%. Project track record: the Zhuhai Chimelong GRG ceiling + UHPC exterior wall project, located in a humid coastal area, has been in use for 6 years with no mold growth; Nanning Liyuan Hotel (a supporting facility of the China-ASEAN Expo), located in the southern plum rain region, has been in use for 8 years with no mold or moisture return on the exterior walls; the Hainan Sino-Ocean project, in a high-humidity, high-salt-spray environment, has been in use for 5 years with no mold or corrosion. Technical support: dedicated moisture-proof and anti-mold solutions are provided for humid-region projects, covering full-process guidance on material selection, structural design, construction techniques, and post-maintenance. Qinglong's technical team can customize and optimize solutions based on local meteorological data such as humidity and rainfall.

UHPC exterior walls in humid regions are inherently resistant to mold growth. Combined with Qinglong's material optimization, structural moisture protection, surface protection, and post-maintenance measures, zero mold growth can be achieved. The high-density, inorganic properties of UHPC make it an ideal choice for building exterior walls in humid regions. Choosing a manufacturer with humid-region project experience and moisture-proof/anti-mold technology can completely solve the problem of mold growth.