GB/T 13477.4-2002 is a part of the standard for testing methods for sealing materials in buildings, focusing on the determination of extrusion of original Encasement single component sealing materials. The standard specifies the determination process and specifies the required test equipment, such as extrusion devices, timing tools, etc. Detailed description of sample preparation, including the original Encasement state requirements of the sealing material. The extrusion difficulty of the sealing material is evaluated by measuring the amount of the sealing material extruded from the original Encasement under a certain pressure and time. This provides a mass reference for the convenient use of sealing materials in building construction, ensuring that the sealing material can be extruded smoothly during construction and ensuring the sealing effect.