改革开放以来，随着国民经济的迅速发展，人民生活水平不断提高，我国新建城乡住宅和公用建筑面积大幅度增加，仅城市住宅每年实际竣工面积为１．２亿平方米左右。新建筑的门窗格式新颖，类型众多，钢门窗、铝合金门窗、塑钢门窗及其它特种门窗正逐渐取代传统的木门窗，其中尤? Since the reform and opening up, along with the rapid development of the national economy, the people’s living standards have been continuously improved, and the area of ​​newly-built urban and rural residential and public buildings in China has increased significantly. The actual area of ​​urban residential housing alone is about 120 million square meters. The doors of the new building are novel in style, with numerous types. Steel doors and windows, aluminum alloy doors and windows, plastic steel doors and windows and other special doors and windows are gradually replacing traditional wooden doors and windows.