Detailed Installation Method of Wood Composite Door

First install the door frame, put it into the door hole and fix it with wood screw, then start drilling countersunk hole and fix it with expansion screw. Then use Styrofoam or cement slurry to fill the gap between the door frame and the wall. After drying, stick the door frame line to it, while use nail gun to nail the door stop line. Finally, install the door leaf according to the position of the door frame hinge.