Installing Pre-hung Doors: 5 Common Mistakes to Avoid

Pre-hung doors already have the doorjamb attached. These doors are available in a number of different sizes from your local home improvement store. Installing pre-hung doors is pretty easy. However, to hang a door like a professional, you need to avoid a few mistakes.

1. Forgoing Shims on Pre-hung Doors

Many novices forgo shims. This is usually the case because they aren’t really sure how to use them. However, shims work wonders when you're hanging a door. Not only will they help a small door fit a larger frame, but they also take up the space that sometimes forms gaps around even the best-measured door. If you notice any gaps larger than 1/4 inch at any place around the door, you should nail a shim in place.

2. Not Finding the Studs

Though you can install pre-hung doors without screwing into the studs, your door jambs may warp or pull away over time. Using a stud finder to locate the studs is easy. Depending on their location, you will find studs every 12 to 16 inches.

3. Not Ensuring Flush Doorjambs

If the doorjamb is not flush with the door opening, you will encounter some serious problems almost immediately. Make sure that the jamb lies flush against the walls surrounding the doors. If the doorjamb sinks below the walls, you will need to use a jamb extender to help it reach. If the door jamb protrudes too far, you will need to plane it down. Make small adjustments. You can always plane the door down more, but once you’ve gone too far, you’ll have an uphill battle. Use a level to make sure that your adjustments have addressed the problem.

4. Failing to Take Accurate Measurements

People often face challenges in home improvement projects because they don’t check and recheck their measurements. You need to purchase pre-hung doors that will fit into your spaces rather easily. If your measurements aren’t accurate, you may end up with a door that doesn’t fit your opening. In the event that your openings are oddly shaped or not a standard size, you should purchase pre-hung doors that are smaller. It is much easier to extend the jamb than to enlarge the door opening.

5. Avoiding a Nail Set

Through the entire process, you should be countersinking your nails for two reasons: You want to be able to paint or stain the door without random nail heads showing through, and a nail head that sticks out may actually cause problems when you open and close the door. Buy a nail set from a local home improvement store and countersink all of the nails. After the installation, you can cover the holes with wood putty.