How to Soundproof French Doors (Interior and Exterior)

Are you irritated by the amount of noise coming through your glass french doors? Wondering how to soundproof them and reduce the noise?

It’s hard to deny it – French doors are stunning. Even the most basic model looks a million times better than ordinary style doors and adds warmth and style to your home. 

But unfortunately, there is a downside. Glass doors are notorious for letting the ridiculous level of noise in. With some models, particularly those that don’t have double glazing windows, you can hear almost everything happening outside. 

Luckily, it doesn’t have to be. Although you might not be able to reduce the noise completely, you can greatly minimize the amount of sound that your french doors let in. 

In this guide, you’ll discover how to soundproof french doors. The advice I’m going to show you will work for interior and exterior french doors. 

Before we get to that, let’s understand why there’s such a problem with soundproofing french doors.

The Problem with French Doors and Noise Insulation

Before I show you how to soundproof french doors, I must first explain how sound travels through such doors. This knowledge will help you understand and apply the following soundproofing tips better.

So, the problem has much to do with the way french doors are made. This also means that you improve their soundproofing qualities by targeting some of those issues.

But let’s start at the beginning – Let’s talk about how noise travels through french doors and what type of sound you hear through them, typically.

Most of the sound you hear through french doors is called airborne sound.

Airborne sound waves are created when sound travels through the air. Take speaking, for example. The sound of your voice makes the air vibrate. Then, that sound travels through the air until it reaches the other person you’re speaking to.

Music, TV, radio, dog barking, and the sounds of a car passing by your house are other airborne sounds.

(A quick side note: The other type of sound we often target when soundproofing is impact sounds. These sounds, in turn, are created at an impact, like stomping or walking. But these sounds are of different nature, and you rarely experience them through french doors.)

Because airborne sounds travel through the air, they also enter houses in the same way. That’s one reason why you hear sounds from the outside louder with doors open. Closing them immediately reduces the intensity of the noise. That is because, with closed doors, there are fewer places through which the sound can enter.

This brings us to the next thing – How sound enters through closed french doors.

Unfortunately, this is because of specific characteristics of french doors.

Think about it – Most such doors are larger than ordinary doors. They feature light construction, with the majority of the doors being taken by glass. 

The additional window panels on each side of these doors might be an extreme example, yet they illustrate the problem well. Most of the wall in this room is glass.

An example of large glass french doors.

Here’s why it’s a problem.

First of all, the doors are larger, meaning more entry points for the sound to get in. With ordinary doors, most of the area around them is a wall. And although walls can let noise in, it’s never as much as what’s coming through the doors. 

You have more gaps and cracks in larger doors through which both air and airborne sound can get in.

(This is important to remember. As you’ll shortly see, you’ll be focusing on those gaps when soundproofing those doors.)

The other problem is that French doors are mostly glass, which makes them poorly soundproofed by default. Glass lets more sound in than most other building materials. Even a double-glazed window isn’t completely soundproof because the glass will let sound in. That’s because, by its nature, glass has low acoustic properties when it comes to different frequencies. 

As Glass on the Web explains:

“A 4 mm-thick glass is rather transparent (poor attenuation measured in dB) for high frequencies at the range of 3500 Hz; 6 mm-thick glass is poor for frequencies around 2000 Hz, and 10 mm-thick glass performs badly at 1300 Hz.”

glass acoustic properties.

(image source)

This also means that you’ll need to use external materials and several soundproofing techniques to soundproof french doors. 

Soundproofing French Doors: Everything that You Need

Below, you’ll discover seven different methods to soundproof your french doors. Each of these methods is relatively simple, but it requires you to use or apply different soundproofing materials. 

To help you get all you need fast, here’s a list of everything the project will require. 

Please note that those links point to Amazon.com. My site is a participant in the Amazon affiliate program, and we may earn a commission if you purchase through our links. 

ProductDescription
Acoustic sealants like Green GlueThe best sealant to fill gaps and prevent sound from entering the apartmentView price
Soundproof weather strippingIncreases the soundproof insulation of the door frameView price
Low expansion foamHelps seal the gap between jamb and wall framingView price
Door sweepHelps seal the gap between doors and the floorView price
Soundproof curtainsAn effective and stylish way to reduce the amount of sound entering a room.View price
Lock and hinge lubricantView price

How to Soundproof French Doors: 6 Methods for Interior and Exterior Doors

#1. Seal all gaps and cracks

As I said above, gaps are the first thing you target when trying to reduce the noise coming through french doors.

And let’s face it – Regardless of whether your french doors are brand new or they’ve been in the house for years, they will have small cracks and gaps. Even a tiny gap of a few millimeters will allow an incredible amount of noise into the house. 

To put this in perspective, according to research, covering just 1% of gaps in the surface can result in up to a 10% drop in noise coming in!

Imagine the results after filling in the gap between the door frame and the floor. 

How do you soundproof those gaps?

Use an acoustic sealant, ideally the Green Glue.

Green Glue is one of the best acoustic sealants on the market. It works just like any other caulk. You apply it with a caulking gun directly on the crack. Your goal is to fill it, just like you would with any other gap. However, given its soundproofing qualities, Green Glue does more than filling the crack. It also prevents various sound frequencies from entering.

Image of green glue, the best acoustic sealant for soundproofing cracks in french doors.

#2. Add soundproof weather stripping to the frame

Once you’ve filled in all cracks between the frame and the wall, the next step is to do the same for the frame.

In this case, however, you don’t fill in cracks by applying a sealant but by adding weatherstripping. But let’s take it from the top.

Your doors might also have gaps between the actual door and the door frame. These might result from poor manufacturing or because the hinges have slightly tilted with long-term use. As a result, the door doesn’t create a full seal with the frame when you close it, leaving microscopic space through which both air and noise can get in. 

Luckily, the solution to this is quite simple – Attach self-adhesive weather stripping to the doorstop, the sides, and the top of the frame. 

EXAMPLE: Soundproof Weather Stripping Door Kit

#3. Add a door sweep at the bottom of the door

This is another simple method to increase the soundproofing of your door frame. The chances are that the biggest gap is at the bottom of the frame. One way to solve it is by installing the weather stripping. 

However, you can also experiment with adding a door sweep. 

A door sweep is an element you add to the bottom of the door that continuously closes the gap between the door and the floor, even when the doors are in motion. Door sweeps are perfect for retaining heat, not letting cold air in but also, blocking the sound from coming in. 

#4. Hang soundproof curtains to block the noise

Let me be clear about this – Despite their name, soundproofing curtains aren’t fully soundproof. This doesn’t mean that they do not help with noise reduction. Quite the contrary. Soundproofing curtains can reduce the intensity of many noises coming into your house from the outside. When you hang them, noises like traffic, barking, and other loud sounds that might be bothering you will be much quieter. 

This is due to certain characteristics of soundproofing curtains:

  • Thickness – Such curtains are much thicker than the usual ones. Because of that, they absorb or block many frequencies from getting in. 
  • Length – Soundproofing curtains are also very long, typically reaching the floor. This way, they leave no additional space for the sound to travel.
  • Density – These curtains are also incredibly dense, making them absorb more sound. 
  • Rough surface – Finally, soundproofing curtains have a rough and porous surface. This prevents sound from bouncing off them and increasing in volume. Rough surfaces absorb part of the sound energy and reflect only what they cannot absorb. This means that the sound that reaches your ears is usually much quieter than without those curtains.

#5. Soundproof air vents above the door

Many french doors come with built-in air vents at the top. There might also be separate air vents in the walls around the door. 

Those vents help improve air circulation in the room but will also let the sound from the outside in. What’s more, air vents might reduce the effectiveness of any other methods you use to soundproof the french door. 

They will continue letting sound in, after all. So, regardless of how well you’ll fill in gaps and cracks, the noise will bother you because of the air vent. 

One way to soundproof the air vent is to remove it and drywall the gap. But I admit that it’s not always ideal to do it and might affect the air circulation. 

The other option is to create a maze inside the air vent.

The whole concept looks like this:

Diagram showing how to block sound coming through an air vent in french doors.

Notice how, with the maze in place, air (and sound) can no longer pass through the vent. The maze makes it more difficult and requires the sound to bounce from one surface to the other. Each such bounce reduces its intensity and volume. 

The simplest method to create the maze is to install wood or drywall panels inside the air vent, to create a structure like in the image above.

Here’s a great video showing how to create a simple DIY air vent.

#6. Finally, don’t forget about hinges and handles

This may not be a method helping to block the outside noise, but it’s also something we often forget. Hinges and handles can create quite a noise, only adding to the frustration of poor soundproofing of glass french doors. 

Without oiling, hinges and handles will not move quietly and will keep squeaking every time you open the door. 

The solution to this problem is quite simple – Oil the hinges. You can use any oil – vegetable oil, machine oil; you name it. 

Or you can get a proper hinge lubricant like Liquidfix. It comes with a dropper and a needle pack so that you have everything you need to do a good and clean job out of the box.

And that’s it…

Use these six ways to soundproof your glass french doors and block the outside noise. 

Good luck!