How to Install A Door
Interior Pre Hung
Installation is Easy
Get professional results, no experience necessary.
Pre Hung Doors
Installing a pre hung interior door is not a difficult project, and is a quick and easy way to upgrade the look of your home. New doors are available in a variety of styles and price points to fit most any budget. You’ll only need a few common tools and by following these simple steps, anyone can get professional looking results, even if you’ve never set a door before. If you want to learn how to install a new door on an existing jamb, check out my how to guide here.
Put Your Level Away
Before we get started, we need to talk about all of the misinformation that is out there. If you’ve spent any time on the internet looking for info on how to set a door, I’m sure you have come across the multitudes of articles that have you start off by checking the floor for level and then immediately cutting the bottom of the door jamb as the first step.
I’m not going to say that that is 100% wrong all of the time, but it is the wrong thing to do most of the time. In a perfect world, you would set the door with the jamb perfectly plumb and the top of the door perfectly level. The door would naturally function perfectly if you set it this way.
Unfortunately, we all live in the real world, where walls and floors are rarely ever perfect- even in new construction. Getting professional results usually involves a series of compromises to find the right balance between perfection and working with the conditions we are given. So put away your level because you aren’t going to need it.
It’s All About The Reveal
When installing a door and casing, the most important aspect of the job that effects the finished look the most is the reveal (the distances between different components). The reveal between the door and the jamb. The reveal between the jamb and the casing. And the reveal between the casing and any nearby walls.
Nothing makes a job look more amateurish than crooked reveals. Most houses have numerous doors that are located very close to perpendicular walls. What if that wall is not plumb and you install the door perfectly plumb? Answer: You’ll end up with an uneven reveal that tapers from big to small. Even a small difference is easily seen by any untrained eye- it just looks wrong. For example- A gap of ¾” at the top tapering down to ½” at the bottom looks horrible.
Check The Rough Opening
Measure the rough opening width in a couple or three places to make sure the new door will fit. The width of the opening should be 2″ larger than the width of you door.
Place The Door in the Opening
Use a shim or two or three at the top of the door frame on the hinge side to keep the door from shifting around while we find out how the door is going to sit.
Place the Door in the Opening
The shims do a great job of holding the door in place so we can find out what were working with. The door jambs sit directly on any finished floor coverings like hardwood or tile, or use a 1/2″ thick piece of scrap as a spacer for carpet.
Check the Reveal to the Wall
If you have any nearby walls, check the reveal at the top and bottom hinges.
Check the Reveal to the Wall
Check the reveal at the top and bottom hinges to the wall. Adjust the door so it is parallel to the wall.
Check the Reveal at the Top
We know that the door slab is square. If we adjust the reveal of the jamb to match the door, the jamb will be square as well. In this example the gap is bigger on the right side than the left, so we can do one of three things:
We can shim the lower hinge side jamb to the right, which will close up the gap at the top. This option would work as long as we don’t have a nearby wall that we need to keep parallel with.
We can raise the hinge side of the jamb or lower the latch side to close up the gap. This option would work if we are leaving a space at the bottom of the jamb for carpet and pad.
If we are setting the door on finished flooring like tile or hardwood, we can lower the hinge side of the jamb by cutting a little off the bottom.
Cut the Door Jamb
Use a speed square as a guide to make the cut. A cordless circular saw is super handy here because we don’t have to bother running a cord for one quick cut.
Check the Reveal at the Top Again
Now the reveal at the top is perfect.
Tack it With A Nail
Position shims to fill any gap between the jamb and the stud. Drive one 15 gauge 2 1/2″ nail just above the upper hinge and below the shims to hold it in place. If you don’t have a 15 gauge nailer, there’s nothing wrong with going old school- 8 penny finish nails with your favorite hammer and nail set.
Tack it With A Nail
Repeat the process and drive another nail by the lower hinge. Now we can move on the the latch side.
Shim the Latch Side
Use shims to adjust the reveal between the door and the jamb.
Shim the Latch Side
We are looking for a perfect even gap. Once it’s adjusted, drive a nail just below the shims. By not nailing through the shims, we still have the ability to fine tune it later if necessary.
Shim the Latch Side
Use some more shims and work your way down. Keep the gap even and drive another nail.
Shim the Latch Side
And finally to the bottom. Usually a door with a reasonably straight jamb leg will only need three sets of shims to get the job done.
The Door is Set
With the door tacked in place, check to make sure it swings freely and that all of the reveals are still perfect.
Check the Stop
The last thing to check is how the door hits the stop. We are looking for the door to make contact evenly with the stop along the entire length. The top looks good.
Check the Stop
Looks good at the middle.
Check the Stop
Perfect at the bottom as well. The reason we only used one nail per shim location previously is so that if we need to cheat the jamb slightly to make the door contact the stop perfectly, it’s super easy to tap the jamb as needed. Once we are satisfied that everything is lined up, we drive two more nails through each set of shims.
Screws
Replace the innermost screw at each hinge with a 2 1/2″ screw driven into the stud.
Screws
A trimhead screw driven into the stud in the corner of the strike plate route won’t be seen once the strike plate is installed, but it will do a great job of making sure the door will function perfectly for years to come.
Trim the Shims
Use an oscillating multi tool to cut off the shims.
All Done
All done with the door install. Now it’s ready for the casing and hardware.
A Note About Safety
Safety is important. I can’t say it any better than my all-time favorite woodworker/ TV host, Norm Abram, so I’ll just leave you with his famous quote:
“Be sure to read, understand, and follow all the safety rules that come with your power tools. Knowing how to use your power tools properly will greatly reduce the risk of personal injury. And remember this: there is no more important safety rule than to wear these (Norm points to his glasses) — safety glasses.”
-Norm Abram, New Yankee Workshop
I just had a conversation with one of my carpenters about something you note here. Rather than running a 2-1/2″ screw through the butt hinge, I install them behind the hinge. It is much easier not to have to match the factory screw and the screw’s finish. Rather just use all the butt screws provided for the hinges themselves. It also makes the next persons job that has to pull those hinges much easier and they won’t have to worry about screwing up the door’s perfect set.
Great tip Guy. Thanks for stopping by!