Installing a Deadbolt

Lead Image
  • 1-3 hours
  • Beginner
  • 45- 150
What You'll Need
Double deadbolt lock set
Variable speed drill
Hole saw
Chisel
Drill bits
Phillips head screwdriver (may be all you need if replacing existing lock)

Installing a deadbolt is one of the easiest and most effective ways to protect your home. In most burglaries, thieves enter the home through a door. The common key-in-knob lock can often be opened in a matter of seconds by a criminal with a credit card or a screwdriver. Deadbolts are significantly harder to get through, and several factors can further increase that baseline of security.

First, let’s address the door itself. There are many different types of doors, and some are more secure than others. Many entryway doors include glass elements, or window panels directly adjoining the door that can be broken out to allow access. Unless your lock is the type a key locks from the inside, a burglar can simply reach through the broken glass and open the door. If the panel is large enough, they can simply climb through it.

If you have a door like this but don't want to replace it, consider replacing the glass panel with tempered glass. This glass is many times stronger than common plate glass and should deter any intruders. Many doors already have tempered glass, because local codes often demand it. If not, take the exact measurements to a hardware store, home center, or glass company and order one. It may be relatively expensive, and often has to be specially ordered, but it's well worth the cost. In any case, whenever a door has standard glass in it or near it, install a double cylinder deadbolt lock so burglars can't open the door by reaching in after breaking the glass.

Study the Door

hand and drill installing a deadbolt lock

Is it a sturdy, well built door? Some newer homes use doors that have a hollow interior (hollow-core doors). These are very easy to break. You may want to consider replacing such a door altogether with a new metal or solid-core door. Although replacing a door may seem intimidating, it's actually quite simple, even for the most novice do-it-yourselfers. You can buy these doors with the hinges and hardware pre-installed in all standard sizes. Simply remove the pins from the hinges of the old door, remove the door, and slip the new door on, and replace the hinges. If the hinges, handles, locks, or strike plates don't match up, you'll have to make allowances for this.

Take Note of Your Hinges

Burglars who succeed in penetrating your home, and who want to remove large items through the door, will not be able to remove the door if you are using a locking mechanism that locks from the inside as well as from the outside and you have non-removable hinges on the door. If the hinges are exposed outside your home, you have a problem—burglars can simply pop out the hinges and remove the door, even when it's locked-up tight.

If this is the case, reinstall the hinges so they are exposed on the inside. Or, replace them with hinges that use set screws so the hinge pins can't be removed. You can also buy kits that allow you to retrofit existing hinges with set screws so they'll be non-removable.

door hinge

Even a high-quality metal or solid wood door with non-removable hinges might be little help if the frame around the door is flimsy. The door can be penetrated with a good shove or the use of a pry bar. The jamb, which is the exposed frame around the door, is made of 1“ wood, which is easy to break with minimal force.

However, this jamb is attached to a 2x4 framing stud. If your hinge screws, strike plate screws, and bolts penetrate into this thicker member, the door is more secure. Replace all these screws in the hinges and strike plates with high quality 3” screws that will penetrate deep into this frame. Using a longer deadbolt will do the same thing.

Consider Replacing the Door and Frame

installing new door with hinges

If there is a gap between the door frame and the wall stud, a burglar can simply push on the frame with a crowbar and pop the door open. Metal strips can be installed around existing doors which will help make the door more secure. Replacing the frame and the door is easier than you think. You can buy doors that are “pre-hung.”

This means that the door is hung in its new frame with all hardware and hinges in place. You take out the old door and frame and replace it with a more secure one. Depending on your siding and interior finish, it can take anywhere from two-hours to two-days to install.

A Few Other Considerations

Installing a deadbolt is a rather simple project and should take no more than two to three hours and require only a few special tools. The main thing is to be sure of the exact location of the holes before you start to drill. If the hole is improperly drilled, it can ruin the door. Also, be sure to use long, three inch screws for the strike plate to penetrate deeply into the frame behind the jamb.

Tip: Replace externally exposed hinges with non-removable hinges exposed only to the interior.

Note: The method for installing the entrance lock is practically the same as that for installing a deadbolt. The differences are that a deadbolt is installed higher in the door and the two pieces of the mechanism attach slightly differently when installed from either side of the door. Otherwise, the techniques are the same.

Choose the Proper Lock Set

deadbolt lock set

Before beginning, choose your hardware, ideally a high-quality brand—this is not an area where you want to cut corners.

There are several different styles and designs to choose from, If the design is a decorative feature, it is a matter of personal taste. However, you need to decide whether you want to use a double-cylinder, double-keyed lock or not. The advantage of using one is that you can lock the door on the way out and no one can open it from the outside or the inside without a key. This stops burglars from carrying things out through your door.

You may want to use an entrance lock that only key locks from the outside, combined with a deadbolt that has a key lock on both sides. This allows you to lock your entrance lock when you are home and not your deadbolt. In case of a fire, you will be able to exit quickly without fumbling for the key to open the deadbolt.

Latch bolts come in varying lengths. You probably want to choose the longest available. When it is needed and hopefully it never will be, it will prove itself to be worth the extra money. Metal stripping can be installed around existing doors to help make them more secure. To create a clean, splinter-free hole, always drill from both sides of the door with your hole saw.

Common Setup Mistakes
  1. Marking the wrong location of the hole
  2. Locating new latch at the same level as the previous strike plate

Templates

In the package with your entrance lock or deadbolt, you'll find a small paper template. This template is made to show you exactly where to locate the two holes you need to drill to install the lock. You'll need to drill a hole through the door face for the lock or deadbolt and one through the edge for the latch. These two holes must be coordinated so the mechanism will properly fit together. The template is your guide to doing this correctly.

First, figure out how high up on the door you want to install the lock. For entrance locks, it is usually 36" above the floor. The main thing to watch for is the location of the old strike plate. If you will not reuse this strike plate be sure you do not install the new strike plate directly on top of the old. The chewed-up area of the frame at this point won't provide a good surface for the new strike plate screws to bite into.

Instructions on the use of the template are usually provided in the package. Most of the time you simply bend the template and wrap it around the door so that one specified side is on the face of the door and the other side is on the edge. Two holes are provided in the template, to make your marks on both the edge and the face. With a sharp instrument or nail, make marks in the doors at these two points.

Check your work to be sure everything is as it should be—you don't want to scrap a good door because a hole was drilled off.

Drilling

hands drilling hole for doorknob

Common Drilling Mistakes
  1. Not drilling straight
  2. Drilling in the wrong location
  3. Using wrong size bits
  4. Drilling all the way through both faces of the door in one pass
  5. Using a dull drill bit
  6. Using a 1/4" drill that is not powerful enough

If you're working with wood or a composite material, you're now ready to do your drilling (metal doors will most likely come pre-drilled). It's best to use a 3/8" drill to provide adequate power to cleanly drill through the solid door. Use the size bits specified by the manufacturer. These are often 2 3/8". You will need a long spade bit to drill through the edge of the door for the hole for the latch, and a hole saw for the hole through the face for the lock itself or deadbolt.

It is important when drilling the larger lock hole through the door face to get a clean cut with no unsightly splinters. To do this, take a look at your hole saw. Note that the hole saw has a small pilot drill in the center. The function of this pilot drill is twofold. First, it allows you to exactly line up the center of the hole saw when you start to drill.

Second, it will poke out the other side of the door before the actual hole saw penetrates all the way through. As soon as you see this pilot bit pop out the other side, immediately stop drilling. Remove the hole saw and start drilling again from the other side of the door. This will create a clean, splinter-free hole.

After the hole is drilled in the face, prepare to drill the latch hole in the edge. Never drill this hole first. Always be sure you're holding the drill level as you drill to insure a straight hole. To drill the latch hole on the edge of the door, use the spade bit specified by the manufacturer. Drill this hole until it meets the larger hole you just drilled. Again, be sure you are drilling straight.

Spring Latch Plate

door handle with spring latch plate

Common Plate Attachment Mistakes
  1. Chiseling the hole sloppily or too deep
  2. Not drilling pilot holes before inserting screws

After both holes are drilled, you can install the spring latch plate. This is a rather simple task and should come out perfectly if you take your time and do it accurately. You will need to mortise the plate into the edge of the door so that it is flush with the surface of the edge.

Place the plate so that the hole in the plate lines up exactly over the hole you drilled in the edge of the door. It's a good idea to actually install the spring latch itself in the door temporarily to be sure the plate is properly located.

Once you're sure the plate is properly placed, hold it snug against the edge of the door. With a sharp pencil or a utility knife, outline the plate on the door. Now you can chisel out this area to a depth equal to the thickness of the plate. This will allow the plate to sit flush with the surface of the edge of the door.

hand and hammer chiseling mortise in door

Use a sharp chisel the same width as the plate, if possible. Use light taps with a hammer so you won't gouge out too much wood and sink the plate too deeply. As always when chiseling, remember that the bevel part of the blade should be digging into the wood. This causes the chisel to always deflect out of the wood and not gouge too deep. Go slowly here to create a tight fit.

When you're satisfied with the fit, you can install the plate with the two screws provided. In situations like this, it makes sense to drill pilot holes first, then screw in the screws. A pilot hole is a hole drilled with a bit that is slightly thinner than the shank of the nail. This pilot hole assures that the screw will go in straight and not split the wood. After the pilot holes are drilled, hold the plate firmly against the door and install the screws.

With the cover plate and spring latch in place, you can now install the lock mechanism. This comes in two pieces, each inserted from either side of the door. Needless to say, be sure the exterior section is pointing out. Slip in the exterior section, threading it through the latch piece, and then the interior. These two are joined together by two screws that insert through the interior section and screw into the exterior section, tightly sandwiching the door and firmly holding the lock in place. Now place the cover plate over the interior section. Finally, slip on the knob. There's usually a spring clip you must press down to slip on the knob. When you release this clip, it fits into a groove.

Strike Plate

hands installing door strike plate

Common Strike Plate Mistakes
  1. Not aligning strike plate with spring
  2. Installing strike plate in old hole formed by previous strike plate
  3. Not using long screws

After your entrance lock is in and properly functioning, you can install the strike plate in the frame of the door. As I mentioned earlier, make sure you're not installing this over the hole created by the previous strike plate, or you will not have good wood to bite into. Of course, it is a little late to be thinking about this now, since the plate must align with the spring latch of the lock you just installed. Just be sure this alignment is exact so the latch will easily insert into the plate and metal liner.

The strike plate is often a three-part assembly made up of a strike frame reinforcer, metal liner, and finished strike plate. The metal liner often requires a rather large hole. To create this hole you can usually drill two smaller holes and chisel this out to create one large hole. Locate the exact center of the strike plate on the frame and drill two holes with a 7/8" bit, one 3/8" above this point and one 3/8" below (refer to manufacturer's instructions).

After these two holes are drilled, forming a figure-eight pattern, chisel out the wood to create one hole that the metal sleeve can tightly fit into. Before installing the metal liner, install the rough strike plate. Again, use two long, 3" screws to penetrate into the wall frame. Be sure to drill pilot holes first. Next, insert the metal liner and then screw in the finished strike plate.

Now test your lock! If it works smoothly and correctly, pat yourself on the back. If it doesn't, back up a few steps and make the needed adjustments.