The quality of the sealing strip is defective or aging: the sealing strip is also the key to the sealing of aluminum alloy doors and Windows. The quality of the sealing strip for aluminium glass entrance doors on the market is very different.  

High quality sealing rubber strip has strong toughness, wear resistance, and not easy to fracture。And the poor quality of the sealing strip is usually very fragile, easy to be corroded, easy to fracture, the sealing effect is also poor.  

The sealing strip is not installed well, and the uneven or bulging situation may also lead to air leakage.