Silicone sealants’ application in the windows & doors and curtain walls includes three aspects: the second sealing for hollow glass, weatherproofing and structural sealing for curtain walls and water and weather proofing sealing for windows and doors. Silicone sealants not only have influence on their safety, but involve in the whole building whether can meet the friendly environment requirements.
Sealing for hollow glass
Hollow glass is the important material to improve the energy saving performance of windows and doors due to its outstanding heat insulation, and widely used in the buildings in the recent years. The inner dry gas in the hollow glass enables to insulate heat and sound, and resists to condensate as well as reduces cold radiation, improving safety of glass.
In the two sealings for hollow glass, the first sealing ensures low water vapor permeability, and the hot melt glue is usually applied. The second sealing aims to guarantee the completeness of glass’ unit structures, and silicone sealant is often used. If the hollow glass is used for the structural assembly, the silicone sealant must be selected.
The shelf life of hollow glass depends on durability of sealing structure, and excellent edge sealing has the following features:
1. Durable weather resistance, especially for heat, water vapor and UV.
2. Strong structure bearing strength, which minimizes the change of water vapor channel of sealants.
3. Low water vapor, and low gas permeability.
If silicone sealant cannot reach the above requirements, the fogging phenomenon probably happens, losing its energy saving performance.
Curtain walls, windows & doors sealing
Curtain walls are made from panels and structures, hanging outside the main structure. They change shapes depending on main structure, and transfer the loading-capacity to main structure. As the symbol of modern buildings, glass curtain walls are more and more widely used . The large amount of glass panels are applied, which provides good light and art design for buildings as well as the weak aspect for energy saving.
In the past, their energy efficiency was how to choose hollow glass with lower thermal conductivity and how to keep the inert gas in the hollow glass and more. But the silicone sealants are not paid much attention to. In fact, silicone sealants’ quality plays an important role for the performance of curtain walls, windows and doors.
First, silicone sealants have a durable bonding strength for curtain walls, and have a direct influence on their gas and water tightness. In fact, the energy consumption caused by failed sealing is much smaller than that of choosing better glass and materials. How to evaluate the energy saving and friendly environment for a building with air and rain leaking issues.
Water and weather proofing sealing for windows and doors is also a systematic engineering as curtain walls. The durable bonding strength, gas and water tightness are all directly dependent on the quality of silicone sealants.
The value of silicone sealants are only 3-5% of the cost of whole curtain walls, windows and doors, however, they can affect quality and energy saving performance for the overall buildings. If the ideal energy saving and sealing is a need, the scientific design and reasonable processing are necessary, but the high quality silicone sealants are a very important factor.