How to Soundproof a Den

Cat Stevens once asked: “Where do the children play?” Well, they could be playing in the den! If it had better sound insulation of course.

A den is a small room in your home where you can do many activities. But if the walls, doors and windows are thin and leaking sound your options might be narrowed to a point where the den is pretty much useless. So how to stop noise from coming in or out?

To soundproof a den you need to do three things. First, seal the gaps in the door frame and the window. Next, add mass to thin barriers such as doors, walls, windows, the ceiling and the floor. The final step involves locating any other sound leaking areas such as air vents and minimizing their impact on sound transmission.

So here are the best ways to do it:

1. Seal any sound leaking areas

You’ve probably noticed that your door frame has a deep crevice along the door. This crevice allows sound to pass easier through the door. The best way to stop this is to cover this gap all across the door with weatherproof foam tape. This is the best foam tape (check the price on Amazon) with different sizes depending on how large the gap is.

When you fill this gap with the foam tape, when the door is closed there will be a seal that prevents draft and much of the noise from passing through. This is a really cheap solution and I recommend using it on windows as well.

But this isn’t the only sound leaking area. The door of your den also probably has a gap underneath it. You know, that gap between the door and the floor. It lets air, sound and nasty bugs crawl inside. The easiest way to take care of this problem is by attaching a door sweep on the door. This is a silicon or a metal attachment that you install on the bottom of the door.

I recommend using this affordable silicone door sweep. It has multiple advantages, but the main one is the easy installation process. First cut it to the required width (the width of your door). Then simply attach it on the door. Since it’s self-adhesive, you don’t have to use any tools for installation such as a drill and screws, which is often necessary with these products.

2. Add mass to thin barriers

Let me first say that you probably don’t have to soundproof all the walls, or the floor or even the ceiling of your den. It entirely depends on your situation.

Are you annoyed by the sound passing through the ceiling? Then soundproof the ceiling. But if the noise doesn’t bother anyone upstairs, there’s no point in soundproofing the ceiling.

The same is true for any other area. But I’ll give you some easy to implement soundproofing tips for each of these areas and you can decide which ones you want to use.

Cover the door with a moving blanket

Once you’ve sealed the gaps in the door frame, the other thing you should consider is making the door thicker and heavier. In other words, making it more difficult for noise to pass through it. There are many materials you can use, such as soundproofing panels, mass loaded vinyl or moving blankets.

I suggest going with one or two moving blankets, because it’s the easiest and most affordable material. Plus, it looks pretty nice. But don’t get just any moving blanket. Get the heaviest one available. And that’s the Supreme Mover blanket.

You can get even better sound blocking quality by using two blankets instead of one. To hang it on the door, use a few tacks or nails. You might need to make a hole for the door handle as well. This can be done easily with regular scissors.

Want to read more tips? Check out my full door soundproofing guide.

Hang a noise-blocking curtain on the window

I’ve covered the best window soundproofing methods already. But I’ll cut it short by sharing my favorite method – hanging noise blocking curtains on the window.

Unlike those basic, light curtains that get moved by the slightest breeze, noise-blocking curtains are much heavier and they provide excellent sound and thermal insulation.

To hang them on the window, you’ll just need a curtain rod. If you’re dealing with a lot of noise, you might want to install a double curtain rod instead. This will allow you to hang two curtains on the same rod and you’ll get a double noise barrier as a result.

I also suggest hanging longer curtains like these Nicetown curtains that I got for my bedroom a year ago. The more of the window area they can cover the better.

Soundproof the walls and ceiling

Many people install an additional layer of drywall for better sound and thermal insulation. But if your room is small enough already, there are better options available.

If you can reach the wall studs, it’s best to place rockwool sheets between the studs. By covering those large empty areas in the wall you can seriously reduce noise. Another great option is to install mass loaded vinyl on the studs with screws and/or nails.

If you can’t reach the wall studs and you don’t want to reconstruct the wall, then I suggest using one of these other options:

• You can hang moving blankets on the wall just like you did on the door. Supreme Mover blankets will do a good job at blocking noise and will also drastically improve the acoustics in the room.
• Another option is to hang soundproofing panels. Go with the heavy stuff that is designed for soundproofing, not just for reducing echo. The best example are these soundproof panels by Burton Acoustix. You can use hanging strips to hang panels on the wall without causing any damage to its surface. Usually two strips are needed to stick the panel. These strips are really effective, because they’re made for hanging large, heavy paintings indefinitely.
• The third option is mass loaded vinyl. It can be used inside the wall or placed directly on its surface. It’s an excellent soundproofing product for blocking all sound wave frequencies. If you’re playing drums for example, this would be the material I’d use. The only downside is the appearance. It’s just a black surface so your den could look strange completely covered in black. But if you use it on just one part of the den it could look fine. You could also paint it with latex paint into any cover you like, or move some furniture around to make it look better.

Any of these three options will provide sound results (pun intended).

Add thickness to the floor

If you want to completely soundproof the floor, you’ll need to install floor underlay, which is basically an additional floor surface, usually made from plywood or MDF panels. Check out my full guide if you’re interested in doing this.

However, this is a lot of work and would require reconstructing the floor. You can get pretty good sound insulation by placing thick and soft material on the floor’s surface instead.

Thick rugs and rubber floor tiles are two great options. I especially recommend this wonderful, extra thick and dense rug pad made from felt and rubber.

Another benefit of covering the floor with this type of material is reduced echo. And the floor will be much warmer to walk on as well.

3. Locate other sound leaking areas

Does your den have an air vent that connects it with other rooms or the outside world? In that case, the noise can easily travel through the vent. In this case you may want to remove the vent and drywall the hole. This is the only way to completely block the sound.

But if you want to keep your air vent functional while reducing noise, then make a labyrinth inside the air vent with small wooden or plastic sticks glued together. Here’s a how-to guide with instructions.

Another potential sound leaking area are cracks in the wall, door or window frame. These cracks can reduce the sound blocking efficiency of any material, especially if they’re deep. You can easily seal these gaps by using a soundproofing sealant.

The best one is produced by the Green Glue company. I’ve reviewed it in this article. It also features a how-to video for properly using it.

Final Word: How to Soundproof a Den

Soundproofing a den or any small room for that matter should be done with soundproofing materials that aren’t too thick.

For example, drywall can be used but it would take away too much space. Placing large foam panels is also not the best idea because the thinner ones don’t block noise and the thicker ones will take away space as well.

So it’s best to go with moving blankets, mass loaded vinyl or soundproofing panels that do a great job because they are much denser than the foam panels.

But the most important thing you can do is seal those gaps in the door and window frame, and make the sure that you add mass to the door and window because they are probably much thinner than the walls of your den. Hope this helps!