On June 10, 2026 local time, the U.S. Department of Commerce announced that it had made a final affirmative ruling on the anti-dumping (AD) and countervailing (CVD) investigations of fiberglass door panels originating in China.
The U.S. Department of Commerce determined that relevant Chinese companies had engaged in dumping and accepting subsidies, causing substantial damage or threatening damage to U.S. domestic industries.
According to the final ruling of the U.S. Department of Commerce, the minimum anti-dumping duty (AD) tax rate is 41.82% and the maximum tax rate is 147.85%. The margin tax rate after deducting subsidy offset factors is 41.79%-147.82%; the minimum countervailing duty (CVD) tax rate is 58.50% and the maximum tax rate is 186.46%.
It is worth noting that the countervailing tax rate has been lowered than the previous preliminary ruling. During the preliminary ruling stage of the U.S. Department of Commerce, the subsidy tax rate for some companies was once as high as 921.42%.
The total minimum comprehensive tax rate of double and reverse tariffs is 108.04%, and the highest comprehensive tax rate is 208.49%. This means that some companies’ products will face additional tariff costs of more than twice the value after entering the US market.
The products involved in this investigation are Fiberglass Door Panels and Fiberglass Sidelites, including finished and semi-finished products, assembled and unassembled products, pre-assembled door system products, and related products that are components of entrance door systems.
The U.S. Department of Commerce’s certification scope covers door panel products containing at least one layer of fiberglass skin, and the main HTSUS codes involved are 3925.20.0010, 4418.29.4000, 4418.29.8030, 4418.29.8060, and 7019.90.5150.
According to the U.S. Department of Commerce investigation documents and public information, the major Chinese manufacturers and exporters involved in this case include Anhui Xinyu Fiberglass Door Co.,
Ltd. (Anhui Xinyu Fiberglass Doors Co., Ltd.), Wuxi Lutong Fiberglass Doors Co., Ltd. (Wuxi Lutong Fiberglass Doors Co., Ltd.), East Grace Corporation, Dalian Capstone Engineering Co., Ltd. (Dalian Capstone Engineering Co., Ltd.), Jiangxi Fangda Tech Co., Ltd. (Jiangxi Fangda Tech Co., Ltd.), among which Jiangxi Fangda Tech and Dalian Capstone are one of the key companies in the US investigation.
Public data shows that the amount of fiberglass door panels imported by the United States from China in 2024 will be approximately US$146 million (approximately RMB 990 million).
Industry insiders believe that when the double-reverse tax rate exceeds 100%, the export competitiveness of China’s fiberglass door panel products to the United States will be significantly affected, and some companies may face challenges such as order transfer, market share decline, and profit margin compression.
At the same time, relevant industry chain companies will also pay attention to the subsequent final damage ruling results of the United States International Trade Commission (USITC) to determine whether relevant trade remedy measures will be formally implemented.
It is worth noting that since this year, the trade remedy investigation launched by the United States against Chinese building materials, industrial products and manufacturing products remains active.
In addition to fiberglass door panels, the U.S. Department of Commerce has previously launched anti-dumping and countervailing investigations into some steel products, packaging materials, wood products and other products.
The industry generally believes that as the U.S. manufacturing protection policy continues to advance, Chinese export companies need to pay more attention to trade compliance risks in key markets and changes in tariff policies.
The final tariff rate for fiberglass door panels’ “double-reverse” tariffs remains high overall, indicating that the United States continues to strengthen trade protection measures in the field of related building materials products.
For relevant manufacturing companies, they need to further focus on market diversification, overseas production capacity construction and trade compliance management in the future to reduce operating risks caused by changes in single market policies.
