How to Replace Your Front Door

An elegant front door with much curb appeal.
  • 3-24 hours
  • Intermediate
  • $200-600
What You'll Need
Tape measure
Pry bar
Nail set
Drip cap
New pre-hung entry system
Levels, two-foot and four-foot
New entry door
Nail gun and compressor
Minimally expanding insulating foam
Interior and exterior molding
Finish nails
New hardware

Installing a new entry door can be the prefect solution when you need to refresh your home's exterior, especially if you’re considering selling. One of the first things a prospective buyer sees is the entry. If it’s inviting, a new entry can create positive attitude towards the rest of the home. Additionally, this is a relatively easy, budget-conscious improvement that can add real "wow" factor to a house.

Types of Installations

There are different types of installations available on the market, each having its advocates and detractors as well as its benefits and difficulties. Learn about each of them so you can decide which is best for your needs and budget.


A pre-fit door has the hinge pockets pre-cut (mortised) and aligned with the existing jamb (of course this assumes the same size door is being replaced). It’s designed to replace your front door without replacing the jamb. In a case where you would use this installation, the door jamb would still be in excellent condition, meaning the opening is still square and plumb. It can be repainted or re-stained if necessary, but any more than that shouldn't be needed.

Hinge size and placement are often standardized with the height of the door, but they are all too often not. For example, you might have custom-sized hinges you wish to reuse that need to be matched to the frame. Measure the placement down the edge of the old door, noting the height from the top and width of the hinges themselves.

The best (although not always easiest) way to make sure your new, pre-fit door is correct is to remove the old door, board up your opening, and take it to the door supplier who can quickly take proper measurements not only of hinge placement, but of door height and width as well hardware placement (and let’s not forget beveling of the door edges). Using your old door as a template, assuming it fits properly, is the most accurate way of pre-fitting the new door. This will assure the installation and alignment of the new door is as straightforward as putting everything back in place.


Over the years doors can settle, sometimes a little (requiring minor tweaking) and sometimes a lot (requiring replacement of the entire entry system). Depending upon the existing conditions, the more experienced door hanger may choose to re-hang the door on the job or even build a unit in place, installing a new jamb. In this case, the door is typically pre-fit but not commercially (not by a third party). Hinges are mortised on the job, by the door hanger — requiring a hinge template, chisel, and hammer. The door may need to be sized for width and height, so a circular saw or table saw may be necessary. A door plane will also be necessary to plane the door for width, and to bevel the edges so they won’t bind on the jamb upon closing.

If a new jamb is being installed, a table saw or miter box will be necessary to miter the jamb, casing, and exterior trim. A finish nail gun would be ideal as well, but at the very least, you'll need a hammer and various sizes of finish nails depending upon the moldings.

A new sill needs to be cut and installed before it's glued and caulked in place. The door installer will have to bore new holes for hardware, either aligned to the existing jamb or both in the door and jamb for a new jamb installation. This requires a drill and appropriately sized bits as well as either an electric screwdriver or manual drivers. Finally, the new system will need to be weatherstripped.


A pre-hung door unit is a modern innovation and rapidly has become the do-it-yourself way to replace an entire entry system. The new door is manufactured pre-hung in new jambs, with weatherstripping systems and bored for hardware. Pre-hung units are readily available in standard sizes at home centers, but they can be custom built to fit the requirements of almost any opening.

While the previous two methods are just as effective at creating the new look you want in your front door, using a pre-hung type is the best way to go to avoid having to hire a pro.

Installing a Pre-hung Door

How to Replace Your Front Door, lock

This installation is straightforward process that may be tackled by a reasonably experienced DIYer. The new door comes already mounted in a new frame, fit to work in the existing opening. Typically hinges are installed, the lockset and deadbolts holes are bored for standard types of hardware, and new molding for the both the interior and exterior are supplied. These new doors and frames are also weatherstripped and designed to be energy-efficient.

Step 1 - Measure

Obviously you will need to measure the existing opening — height, width, and depth of the door — before you can replace it with a pre-hung unit. Measure the wall condition, or width of the jamb, from the inside to the outside first. Jamb widths vary with the type of framing. Pre-hung units for a 2x4 framed wall come with a 4 9/16-inch jamb plus a two-inch exterior molding, like brick mold. Larger standard units for 2x6 walls are available. Other things can affect the wall condition, such as sheathing, drywall, plaster, and siding. Accurate measurements are necessary so you know ahead of time if a standard jamb may need to be extended to meet the requirements. This might not be your ideal solution if the standard pre-hung size isn't quite right, but keep in mind that while custom size doors are available, they take a while to produce and come at a much higher price point.

Typically, a do-it-yourselfer takes measurements of the existing finished opening to compare against the new pre-hung unit. You need, however, to measure what is called the “rough opening.” This is the dimension of the opening without the door and jamb — trimmer to trimmer and header to floor. It is good to leave half an inch in height and one inch in width between the outside dimensions of your new pre-hung piece and the rough opening for shimming and squaring your new door.

Measuring rough openings can be misleading. In older homes, existing jambs were usually thicker, making the opening wider. Meanwhile, homes built on raised foundations have what is called a raked sill, which can add 2 1/2 to three inches to the rough opening's height. Also, over the years, people may have added to an entrance way by putting down permanent flooring of some sort, which can shorten the height. Bottom line is you need to compare these measurements to the standard measurements of the new pre-hung unit.

An additional consideration is the nature of the exterior opening, i.e. is the exterior wall masonry, brick, stone, stucco, or wood. You need to measure the outside of the new unit’s exterior casing against the masonry opening.

Step 2 - Remove the old Front Door

After accurately measuring and determining that you can use a pre-hung system, it's time to remove the old door. Make sure first that both the interior and exterior trims have been pulled off. Some new door frames will come with exterior trim attached and you may not have to use the existing trim, but it is better to play it safe and keep it all in one piece. Ease the end of a pry bar between the casing and the wall or siding and carefully pull it free.

Next, remove the hinge pins so you can detach the door itself from the jamb. A hammer and nail set or a screwdriver can help you with these pins if they're particularly difficult. Once the door is out of place, unscrew the other half to the hinges as well.

Detach the sill and the jamb from the house frame by unscrewing it or pulling up the nails holding it in place. Remove any shims as well before using a pry bar to take care of the door frame itself.

Step 3 - Fix the Weatherproofing

Removing the old door can affect the waterproofing in your wall. If you have a large overhang, this is typically not an issue, but if there is a minimal overhang and your door is exposed, you need to examine the opening to make sure there is no water damage. Replace flash, and fix the waterproofing as necessary. This might involve installation of a drip cap over the door to divert water and/or reinstalling waterproofing flashing in the wall prior to installing the new unit.

Step 4 - Set the Sill

The next step is to prepare the sill to establish the proper height. This can be done with treated lumber, which can be glued and screwed to the deck. It is important that the sill plate be level, so use a two-foot level to test it.

Step 5 - Install the Frame

Following the manufacturer’s instructions, set the door frame in the opening applying a bead of caulk as shown in the instructions. Use your four-foot level to make sure the new frame is plumb and square in the opening, shimming as necessary.

After re-hanging the door in the frame, checking to see that the door is operating properly, i.e., the margins around the door are consistent and within tolerances, and the door is not binding. Then, nail the frame in place through the jamb and shims.

Step 6 - Insulate

The next step is to insulate and caulk the frame in place between the jamb and framing material with an expanding foam. Make sure to use a minimally expanding foam. It cannot be stressed enough that this insulating foam is not a substitute for proper waterproofing.

Note: If the gaps are larger than recommended by the manufacturer you may have to add larger shims and/or fiberglass insulation.

Step 7 - Add Casing and Hardware

The interior casing can now be applied to finish the interior opening, and hardware (locks, deadbolts, and/or handles) can be installed.

Step 8 - Finish

Exterior doors have been traditionally made of wood, but today they are manufactured from fiberglass and composites, making them much more durable. The new systems can come raw, allowing for custom finishing, or factory finished. If your new unit is raw, you need to immediately finish all exposed edges, which includes removing the door from the frame so as to be able to thoroughly seal the top and bottom.

Tip: If a door warps or cracks, the first thing the manufacturer will look to void their warranty is improper sealing of the door.

The Moral of the Story

Installation of a new entryway can be a straightforward DIY project, but depending upon your particular situation, your budget, and the statement you wish to make, it can much more complicated. It is the face of your home, so it’s worth the effort to do it right.