A well-made wood door can be a beautiful addition to any room. A damaged wood door, however, can be an eyesore, and unless you repair the damage it may compound until the door becomes useless. Fortunately, repairing a wood door is not a difficult task, merely requiring a bit of detailed work to repair even major damage in such a way as to restore the door so that it can once again add to the ambiance of your home.
Remove the door from the opening and place on the sawhorses. Remove all the hardware from the door, including hinges, doorknobs and locks. Sand any paint or finish from the surface of the door until you come to the bare wood, wiping away the wood dust using a tack cloth. Clean the wood's surface with mineral spirits.
Repair any holes in the door. For large holes in a paneled door, the best way to repair is to remove and replace the panel entirely. Remove the mouldings that hold the panel in place, using a claw hammer, and then replace the panel with another, restoring the mouldings to hold the new panel. For a hollow door, or on doors where the panels are routed in, fill the hole with spray foam insulation, and allow it to dry overnight. Cut off the excess foam using a razor blade, and cut away a slight layer of foam within the hole. Apply a layer of vinyl spackling compound to the hole, smoothing it to the surface of the door, and allow it to dry. Sand the vinyl patch smooth and level with the door's surface.
Repair the cracks that may have developed in the door's surface using wood glue. When the glue has finished drying, sand the repair area until it is level with the rest of the door's surface.
Fill any gouges in the door's surface with wood putty, sanding the putty smooth and level once it's dried.
Use an epoxy filler for any missing sections, shaping the filler as needed, and sanding it smooth and level when it is dry.
Use the sandpaper to remove any remaining minor scratches in the surface of the door.
Finish the door's surface according to personal tastes, either with paint or wood stain. Paint the door, beginning with the panels, then the door's surface, finishing with the mouldings. When painting, apply a primer coat, allowing it to dry completely before applying the final color. Or apply a wood stain to finish the door, using a lint-free cloth. When using a stain, apply at least two coats, allowing the first to dry before applying the second. Apply a layer of polyurethane clearcoat to the stained surface for additional protection from the elements.
When dry, reinstall the door hardware, and hang the door back into place.