Deadbolt Installation Alert: How To Install A Deadbolt On A Metal Door?

Key Takeaway

  • If you want to install a deadbolt lock on your metal door, you should start by drilling a smaller hole and gradually increasing the width.
  • Drill holes in the suitable locations and install the deadbolt by assembling the lock components well into the door.
  • To ensure that the deadbolt works smoothly, make sure the screws are not overtightened.

Deadbolts can be tricky to install, especially if you are the first timer with the drilling job involved in the procedure. The task can get all the more challenging when you have to install a deadbolt on a metal door. No doubt, drilling through a metal door is more complex than drilling through a wooden door. However, it can still be DIYed, following particular instructions and precautions.

Having the appropriate tool for the job will make it much more manageable. First of all, to drill through a metal door, you need special drilling bits that are not only hard and abrasive but also heat-resistant. Cobalt bits or Nitride coated bits can do this job well for you. 

This article will guide you to learn how to install a deadbolt on a metal door. We will discuss the required material, the steps to the process, and certain essential things to keep in mind while drilling through a metal door.

Is Drilling A Metal And Wooden Door The Same?

While drilling through wood may be an easy task to carry out for a first-timer trying to install a deadbolt, the task gets more challenging as you drill through a metal door. 

First of all, regular drills do not bore through metals effectively, as the drill bit may get damaged during the drilling process unless you are punching through a thin metal sheet. Secondly, drilling through a metal door requires you to use certain techniques that a layman might not know. For example, you need to create a dimple using a hammer that will prevent you from straying while drilling or drill at a slower speed to avoid overheating the bit.

To answer the question straightforwardly, drilling through a metal door is more complex than drilling through wood and requires special tools, techniques, and precautions.

Points To Keep In Mind While Drilling Through Metal Door

Points To Keep In Mind While Drilling Through Metal Door

Here are certain essential precautions and techniques that one must follow while looking to add a deadbolt to a metal door.

1. Create A Dimple On Your Door

When you start drilling on a metal surface, drill bits tend to wander due to a lack of friction. Using a center punch and hammer to make a small dimple will provide the tip of your drill bit a point to ride in as you carry out the drilling process.

2. Don’t Miss Out On Wearing Protective Gear

Ensure that you wear gloves, eye protection, and a facemask for your safety when you begin the drilling process, as it takes only one tiny piece of metal to cause a serious injury.

3. Lubricate The Drill Bit For Easy Passage

Using lubricating oil, cutting fluid, or multipurpose oil while drilling 1/8 inch or thicker holes in metal that is 1/8 in. or thicker makes the drilling process easier by reducing the friction and also extends the life of the drilling bits.

4. Consider Beginning With a Smaller Hole

Most deadbolts require a 2 ⅛ inch hole to attach the cylinder, which may be challenging to DIY. However, you can make the task simpler by starting with a small ¼ inch hole and drilling the same hole with thicker drills to make it bigger until you achieve the size that you need.

5. Drill At A Slower Speed

The faster you operate your drill on a metal, the hotter it gets causing damage to the drilling bit. It’s best to drill through metal at the slowest possible speed with a metal drill bit. In fact, hard metals, such as steel, necessitate even slower rates. While a wooden door may be drilled through at 3,000 rpm, a metal door should be drilled at 350 to 1,000 rpm.

Tools Needed To Install A Deadbolt

Determine whether you are looking for how to install a deadbolt on a wood door, a fiberglass door, or a steel door and, accordingly, prepare the necessary tools. 

  • Measuring Tape
  • Screwdrivers (Flat-head and Phillips-head)
  • Drilling Tool and bits sized ¼ inch and above
  • Masking Or Painters Tape
  • Hammer
  • Pencil
  • Chisel
  • Deadbolt
  • Batteries (In case Of Electronic Deadbolt)
  • Eye Protection
  • Dust Mask
  • Gloves

How To Install A Deadbolt Lock On Metal Door

How To Install A Deadbolt Lock On Metal Door

Once you have a basic understanding of drilling through a metal door, you are in a good position to learn how to install a deadbolt on a metal door. All you need is a few essential tools, as mentioned above, and you are good to go. 

If you want to replace a deadbolt lock on your door, first read one of my articles about removing a deadbolt lock to remove the existing deadbolt properly, and then follow the instructions below.

  • Step 1: When you are ready to put a deadbolt on your metal door, the first thing to consider is where you want the deadbolt to be installed. It is essential to understand how high a deadbolt should be on a door. The deadbolt height on your door should be between 6 and 12 inches above the door handle or 44 inches above the bottom of the door.
    deadbolt height on your door
    Determine a good location for the lock using the measuring tape and mark it with a speed square and a pencil or marker. When marking the position, make sure to indicate it on both sides of the door, inside and outside.
  • Step 2: In your deadbolt kit, look for a paper template. The template assists the user in drilling the holes in the door correctly. 
    holes in the door
    Generally, the template is included with the lock’s instruction booklet. Unfold the template and use painter’s tape to secure it to the door. In most cases, the template extends from the outside of the door to the inside of the door.
  • Step 3: After placing the template on your door, use it as a guide and carefully drill a hole in your door with the hole saw attached to your power drill. It is not necessary to remove the template and just drill through it.
    drill a hole
    Most deadbolts require a 2 ⅛ inch hole to attach the cylinder, but it is not a universal measurement. Referring to the instruction manual of your deadbolt is your safest bet.  
    Since you are going to shrill through a metal door, the process requires a certain special technique. 
    First, take an awl or similar object, place it at the point where you would drill the door, and tap the rear of the awl with a hammer. This will create a dimple on the door so the drilling bit and drill through the door without straying.
    Next, start drilling with a ¼ inch of Cobalt or Titanium drilling bit, then keep increasing the size by redrilling with a thicker bit. Repeat it until you achieve a hole of the required radius.
    Also, ensure that you are wearing gloves, eye protection, and a face mask for your safety when you begin the drilling process, as the pieces of metal can cause severe injury. 
  • Step 4: After drilling a hole for the lock body, travel to the edge of the door to drill the second hole. The second hole bored on the edge of the door allows the bolt to go in and out. The paper template will assist you in correctly positioning the hole.
    positioning the hole
    Drill a 1-inch wide hole following the same technique mentioned in the above steps. Continue drilling until the hole meets the previously created hole.
  • Step 5: It is now time to align the faceplate with the edge of the door. Install the faceplate and bolt simultaneously, as both of these would most likely be joined. Insert the bolt into the 1-inch hole, and seat the faceplate flush against the edge of the door. Match the hole in the plate with the hole drilled on your door’s edge.
    align the faceplate
  • Step 6: It is now time to install the door’s lock mechanism. The two pieces of the deadbolt body must be installed, one on each side of the door. If you’re installing a single-cylinder lock, make sure the keyed cylinder is on the outside of the door. At this point, you may need assistance holding the two parts of the lock mechanism together.
  • Step 7: After that, align the slot on the thumb turn with the tailpiece and secure it to the door with two self-guiding long screws. The bolts should then be screwed into position with a manual screwdriver, as electric screwdrivers do not work well on metal doors. 
    align the slot on the thumb turn
    Make sure that you don’t over-tighten the screws otherwise it will affect the smooth functioning of the lock.
  • Step 8: After adequately installing the lock on your door, evaluate the smoothness and precision of the deadbolt’s operation. Adjust the screws as needed if you feel any obstruction or harsh movement.

Frequently Asked Questions

Q1. Is a Cobalt drilling bit better to drill through metal than a Titanium bit?

Answer – Though both the drilling bits do their job reasonably well, I prefer a Cobalt drilling bit over a Titanium one for more than one reason. Cobalt drilling bits can be sharpened, unlike Titanium drilling bits. Also, Cobalt drill bits are very hard, highly abrasive, and heat resistant.

In my opinion, they are the most ideal for drilling through hard metals like cast iron, stainless steel, titanium, etc.


Placing deadbolts on metal doors is more complex than installing them on wooden or fiber doors, but it is still doable. A relatively basic understanding of the interior of a lock, as well as several crucial aspects regarding drilling into metal, will assist you in completing the task successfully. However, I recommend taking specific measures to avoid injury.

This article describes how to install a deadbolt lock on a metal door in a few simple steps.  If you want to put a deadbolt on your metal door, you’ve probably found this post helpful. If you have any further questions related to deadbolt lock installation, please leave them in the comments area. I would be delighted to assist!

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Hey! I am Mark. Though I am not a locksmith by profession, but locks have always fascinated me since my teens. And it all started when I got locked out of my house and I had to pick the lock. Since then it has become my hobby to learn more about different kinds of locks, understand their working and methods to pick them up. In due course of time, I have also become better aware of how installing the right lock goes a long way in ensuring iron clad security. I aim to share my passion (about locks) through this blog. If you are also passionate about picking locks or are just looking to beef up the security, hop on the ride.