In building ventilation systems, silicate boards are widely used due to their fire-resistant, moisture-proof, and corrosion-resistant properties. However, after prolonged use, some projects have experienced delamination of these boards, which not only compromises the system’s airtightness but also poses potential safety hazards. At the root of this issue, delamination is closely linked to material characteristics, installation techniques, environmental factors, and inadequate maintenance.

　　The core component of silicate boards is inorganic silicate. Although these boards exhibit excellent thermal stability, when exposed for extended periods to high-temperature and high-humidity environments or conditions with drastic temperature fluctuations, moisture inside the boards gradually escapes, leading to a loosening of the microstructure. Particularly at the bonding interface, if oil stains or dust are not thoroughly removed during construction, an isolation layer may easily form between the board and the adhesive, thereby weakening the bond strength. Moreover, ordinary cement mortars or organic adhesives may undergo hydrolysis under continuous damp and hot conditions, further reducing their bonding performance.

　　Vibration and airflow impacts from the ventilation system can accelerate fatigue damage at the edges of the panels. If the spacing between fixing points is too large during installation or if elastic gaskets are not used for cushioning, the stresses generated by thermal expansion and contraction cycles cannot be relieved, ultimately leading to localized cracking or complete detachment of the panels. It is worth noting that when panel thickness varies unevenly or the curvature design is unreasonable, areas with concentrated stress are more likely to become the starting point for detachment.

　　Environmental factors significantly affect the durability of silicate boards. In humid environments, after absorbing moisture, the boards experience a change in their coefficient of thermal expansion. Moreover, if the external insulation layer of ventilation ducts is damaged, condensation can seep in and directly erode the adhesive layer. In industrial settings with high concentrations of corrosive gases, acidic or alkaline substances may undergo slow chemical reactions with the silicate material, gradually breaking down the chemical bonds between the substrate and the adhesive.

　　Preventing detachment requires a holistic lifecycle management approach. During the design phase, the thickness of the panels should be appropriately matched to the ventilation pressure, and products with high density and low water absorption should be prioritized. During construction, the substrate surface must be thoroughly cleaned, and specialized adhesives resistant to damp-heat aging should be used. During operation, adhesive joints should be regularly inspected, and stress concentration areas should be monitored using technologies such as infrared thermography to promptly repair any microcracks. For panels that have already detached, the failed adhesive layer should be removed during repair, the cross-section should be re-sanded, and the structural integrity should be restored by combining mechanical anchoring with adhesive bonding.

　　The detachment of silicate boards is not caused by a single factor but rather results from the combined effects of materials, manufacturing processes, and environmental conditions. By optimizing material selection, standardizing construction practices, and conducting periodic maintenance, we can significantly extend their service life in ventilation systems and ensure both the safety and functional stability of the project.