The building curtain wall is the iconic outer coat of modern buildings, and the curtain wall sealing strip is the vital “invisible guardian” of this coat. Although it is inconspicuous, it directly determines the air tightness, water tightness, sound insulation effect, service life and even the overall energy-saving performance of the curtain wall. Faced with a wide variety of curtain wall sealing materials on the market, how to make a wise choice for your project? This requires consideration from several core dimensions.
Weather resistance and environmental adaptability are the cornerstones of curtain wall sealing strip material selection. Curtain wall sealing strips are exposed to the outside all year round and must withstand the harsh test of sun, rain, cold and heat. EPDM has become the mainstream choice in the market with its excellent ozone resistance, UV resistance, extreme temperature resistance and excellent anti-aging performance, especially suitable for conventional climate zones and high UV radiation areas. For projects located in extremely cold or ultra-high temperature areas, such as Northern Europe or the Middle East, special attention should be paid to the low-temperature brittle temperature of the material and the performance stability at high temperature to ensure that the material will not fail under extreme conditions.
Good mechanical properties are the guarantee of long-lasting sealing effect. The curtain wall sealing strip needs to maintain excellent resilience after long-term pressure in order to effectively fill the gaps between curtain wall components. Among them, “compression permanent deformation rate” is a key indicator. The lower the value, the stronger the ability of the material to return to its original state after the pressure is released, thereby ensuring a long-term sealing effect. EPDM and TPV usually perform well in this regard. At the same time, the hardness and tensile strength of the material also need to be moderate to resist the stress caused by wind pressure, structural settlement or thermal expansion and contraction, and avoid tearing or excessive deformation.
Environmental protection and safety performance are increasingly attracting global attention. With the tightening of international environmental regulations and the popularization of green building concepts, curtain wall sealing strip materials must comply with strict environmental protection directives such as RoHS and REACH. Low VOC emissions are the basic threshold to avoid pollution to indoor air quality and improve the health level of buildings. High-quality EPDM, silicone and some standard TPV materials can meet these stringent environmental requirements.
For special application scenarios, material selection needs to be more targeted. For example, in super high-rise buildings or fire partitions, materials with high flame retardant grades, such as specially formulated silicone rubber or flame retardant EPDM, should be preferred to meet building fire protection regulations. For the parts where the glass curtain wall contacts the metal frame, sulfur-free and halogen-free sealing strips must be selected to avoid electrochemical corrosion. If the project is located in an industrial area or needs to be frequently cleaned and faces corrosion from special chemicals, the excellent chemical resistance of silicone rubber may be a better choice. In dynamic joints with large structural displacements, high elasticity and low modulus materials are required to better adapt to deformation.
The final choice is a comprehensive balance of performance, cost and long-term value. Although the initial purchase cost is an important consideration, the full life cycle cost of the material should be taken into consideration. High-quality EPDM is usually the ideal choice for most projects due to its excellent comprehensive performance and high cost-effectiveness; silicone performs unparalleled in extreme temperatures, but the cost is relatively high; TPV’s recyclable properties are unique in projects that emphasize sustainability. Communicating your specific project needs with an experienced curtain wall sealing strip supplier – including geographic location, curtain wall system design details, performance level requirements and budget range – is a key step in accurately matching the most suitable materials.
Selecting curtain wall sealing strips is no small matter. Only by deeply understanding the characteristics of the materials and strictly controlling the performance, environmental protection and adaptability can we put on a long-lasting and reliable “invisible armor” for the building, silently guarding its safety, comfort and high efficiency energy saving over the long years, and making the building’s gorgeous coat last forever.
