For the window and doors, the quality is most important part. Especially the nowadays, people love to use large glass windows to decorate their homes for good sight view and scenery. At Xiamen KDSBuilding Material Co., Ltd., we believe that product quality is built into every stage of production—not simply checked after a window or door has been completed. For international customers, quality means more than good appearance. A reliable window or door must have accurate dimensions, stable operation, proper sealing, suitable materials, reliable hardware, and consistent performance. That is why KDSBuilding has established a quality control process covering materials, production, assembly, inspection, packaging, and continuous improvement. 1. Quality Starts with Raw Materials The first step in quality control is selecting and checking the materials used in production. Before materials enter production, our team checks the specifications and appearance of aluminum profiles, PVC profiles, glass, hardware, seals, reinforcement materials, and other components. For aluminum windows and doors, factors such as alloy, profile thickness, dimensions, surface finish, and color consistency are important. For PVC products, profile specifications, reinforcement, chamber structure, and surface quality also need to meet the requirements of the order. Glass is another critical component. Depending on the project, customers may require clear glass, tempered glass, laminated glass, Low-E glass, double glazing, or triple glazing. The glass specification, thickness, configuration, and appearance are checked according to the order requirements. By controlling materials at the beginning, we can reduce quality problems later in the production process. 2. Standardized Production Processes After materials are approved, production follows established procedures. Depending on the product, the process may include cutting, CNC machining, drilling, corner assembly, reinforcement installation, hardware installation, glazing, sealing, adjustment, and cleaning. For customized windows and doors, production drawings and order specifications are particularly important. Dimensions, opening styles, glass specifications, hardware, colors, and other details are checked before production begins. Our production team follows the approved product information to reduce mistakes caused by incorrect dimensions or component selection. Standardized processes also help improve consistency when producing multiple windows or doors for the same project. 3. Checking Dimensions and Assembly Accuracy Dimensional accuracy directly affects installation and product performance. During production, key dimensions are checked according to the product drawings and order requirements. Frame dimensions, sash dimensions, diagonal measurements, profile connections, glass installation, and hardware positioning are among the areas that require attention. For doors, additional attention is given to frame alignment, hing...