Fitting an exterior door is a difficult process that requires attention to detail and a strong dedication to completing the job properly. Fitting an exterior door may be a necessary step in the remodelling process and can save you hundreds of pounds in labour and installation costs if done yourself. While it may be a difficult process, it is certainly doable if you follow the proper instructions.
Stand up the door in front of the existing door frame and use a pencil to mark the adjustments on the door that will need to be made. Make sure there is a 2 to 3 mm (5/64 to 1/8 inch) gap between the door and the frame on both sides and at the top to make room for necessary hinge connection and movement.
Use a plane to shave away the wood along the side of the door. Always begin at the edge of the door and move in towards the middle. If you need to make adjustments that are more than 1.2 cm (1/2 inch), it is recommended to use a circular saw as it will make for an easier trimming process. Continue to trim the wood until it has reached the necessary size to fit the door frame. Never shave wood inside of the marked pencil lines.
Mark the position of where the door hinges will attach on the door frame. Hold the door upright against where the door is going to be placed and make precise marks using your pencil as to where the hinge will connect. Drill pilot holes into the door at the marked spots to prevent the door from splitting once it is attached to the hinges.
Attach the hinges to the door using screws that fit the hinges you intend to use (the size will vary depending on the hinges). Screw the hinges into place by attaching only one screw to each at first and test to see that the door opens and closes. Once the test has been completed, drill in the remainder of the screws. Complete a final test that the door opens and closes normally and that the door is level.