How To Install A Door Knocker On A Fiberglass Door

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There is probably nothing that gives the traditional feel to modern entry doors quite like a door knocker. Combining the old style with the new one sounds easy. But it can be demanding, especially when you are dealing with fiberglass. So we looked for ways you can mount a door knocker to a fiberglass door. 

There are two mounting methods you can utilize to install a door knocker to a fiberglass door. They are as follows:

  • Surface mounting – This installation method requires you to drill a hole on the fiberglass door where you can insert the screw that will hold the door knocker in place. 
  • Through-the-door mounting – For this installation option, you will need to bore a hole from the interior side to the exterior side of the door and use bolts to fix the door knocker in place.

Let’s dig deeper into this post. Keep reading and learn in detail which of these two methods is the suitable way to mount your door knocker.

woman holding at the door using the old door knocker. How To Install A Door Knocker On A Fiberglass Door

Installing a Door Knocker on a Fiberglass Door

Before you start installing the door knocker, however, there are two things to keep in mind: your safety and the tools to use. 

The first thing to remember when planning on working with fiberglass is equipping yourself with protective gears, such as the following: 

  • Eye goggles
  • Long sleeves and pants
  • Face mask
  • Construction work gloves 

Using this gear will help prevent you from accidentally ingesting and breathing the microparticles of fiberglass that can cause allergy and lung problems. According to the Washington State Department of Health, micro-fiberglass can enter your body through your eyes, nose, and skin pores and aggravate any existing ailments. 

Secondly, you will need to prepare the following tools beforehand:

  • Electric drill and special bits
  • Screwdriver
  • Ruler
  • Screws
  • Stove bolts (only applicable for through-the-door-mounting)
  • Small crescent or socket wrench
  • Pencil and paper

With that covered, let us now go into the details of the door knocker mounting options.

Surface Mounting

Surface mounting is suitable for homeowners who prefer a clean and chic appearance of the interior or exterior sides of the door. Below are the quick steps to follow for this mounting option:

1. Measure the thickness of the fiberglass door in inches to ascertain the depth of the hole you want to drill. In general, fiberglass doors are 1 3/4 inches thick from the interior to the exterior. You have to drill halfway through that thickness. 

2. Position and hold up the door knocker on your determined mounting area, preferably at the center. Use a pencil to mark two spots for the screws.

3. Create indentations on the mark by gently hammering a nail or awl. The indentations can facilitate faster drilling. 

4. Prepare either high-speed steel (HSS) drill bit or titanium-coated drill bit and cover the upper part with masking tape, making sure that only half appears. 

5. Drill two pilot holes on the mark. Make sure the diameter of the pilot hole is as big as the root circumference of the screw.

6. Position and attach the door knocker on the fiberglass using an electric screwdriver. You now have installed the door knocker.

Check out this Adonai Hardware’s decorative door knocker on Amazon.

Through-The-Door Mounting

If you want to keep the door knocker in place for years to come, you may opt to use the through-the-door mounting method, which provides a firmer and more stable grip on the fiberglass. 

This process is slightly more complex as you have to drill fully through the fiberglass, which may crack the material. But do not worry. We detailed the process below so you can avoid that from happening:

1. Position the door knocker on your determined mounting area, and mark with a pencil. Then create indentations using a nail or awl. 

2. After that, measure the width and height of the exterior door and list down the marking measurements. 

3. Also, mark the interior door with the measurements you listed. Ensure the mark in the interior door is the same as the exterior door to avoid drilling disaster. 

4. Drill through the fiberglass door using a titanium-coated drill bit for this method as they are stronger than the regular HSS bit. Stop drilling halfway through, and start again on the mark on the interior side of the door. By doing so, you can prevent the fiberglass from cracking or chipping due to the centrifugal force and heat created by the drilling bit.

5. Insert the stove bolts from the interior side of the door until it slides into the door knocker screw hole. Tighten the bolt’s grip using a screwdriver or a wrench. You do not have to worry about over-tightening the stove bolts as fiberglass is impervious to hot or cold weather, which prevents it from shrinking or expanding.

How do I choose a door knocker?

Which of the above methods are you going to use? We can only guess since we have different preferences. 

Speaking of guesswork, homeowners usually only guess when choosing door knockers. We want to change that, so we also listed two criteria you can use in deciding what door knocker will fit your entry door:

Mounting Type

Go with through-the-door knockers if drilling a permanent hole on both sides of your door does not bother you. Otherwise, opt for knockers you can mount on the surface of your door. Just remember that the through-the-door method is much more stable than surface mounting. 

See this Renovators Supply’s oak leaf door knocker on Amazon.

Door Style and Property Type

It is undeniable that some homeowners are all about style when it comes to their entry doors. That is why a considerable portion of the decision-making process is on door knocker style matching

Check out this Hanzla Collection’s antique brass dook knocker on Amazon.

How high do you put a door knocker?

When installing door knockers, standard height placement requirements do not exist as variables like door design, height, and width are at play. 

However, we suggest choosing a height somewhere 4 and 5 feet from the bottom of the door. In addition, you will never go wrong placing the door knocker at around 5’6″ to 5’10” feet, the average adult eye level

When in doubt, reference the average height of the adult people in your home and make that the basis for how high you should mount your door knocker. 

Do you need special drill bits for a fiberglass door?

Yes, you need special drill bits when drilling a fine hole on fiberglass. In the methods above, we recommend using high-speed steel (HSS) drill bits and titanium-coated drill bits since they are more durable than regular drill bits that can easily take damage after a few rotations on the fiberglass door. 

These two types of drill bits provide a more stable rotation while working on fiberglass. They create less heat, friction, and vibration that can crack or chip the fiberglass. As a result, holes created on fiberglass have minimal edges. 

What kind of screws to use on a fiberglass door?

Just like specialized drill bits, there are also screws only made for fiberglass. 

There are 3 kinds of screws you can use for fiberglass:

  • Snug fastener SNG221
  • Tight-point FLAT-ZIN875-100
  • Tight-point FLAT-ZIN6100-100

These screws can cater to the composite nature of fiberglass, meaning they guarantee that the fiberglass does not crack during and after inserting. 

In Summary

When trying to mount a door knocker on your fiberglass door, the easier way is by simply attaching it with a screw from the exterior side of the door. But if you want to fasten it to the door more tightly, locking in the screw or bolt from the interior through the exterior provides a better mounting capability. Either way, the result will still be impressive, accentuated fiberglass. So get to work and install that door knocker and let everyone admire it.

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