Creating a soundproof generator box around a portable generator can make a huge difference regarding the noise without interfering with its function.
I live in an area with highly volatile weather that often ends up causing troublesome power blackouts. Because of that, I know just how grateful I am to have a good and functioning generator in my home. Other people use generators to keep themselves supplied with power during outdoor trips when they spend nights in the wilderness. However, what all generator owners have in common is knowing just how loud and distracting those machines can get.
For a while, I tried to simply put up with the noise, set in my opinion that the benefits of owning a generator outweigh the drawbacks. Still, at some point, I decided to take action and look for a solution to the noise. To my great joy, I discovered soundproof generator boxes. These devices are so simple that you can make them on your own. They can muffle the noise from a generator so that it doesn’t bother you at all.
Building a soundproof box around a portable generator can make a big difference in terms of the noise without interfering with the generator’s function. Those who want a premade solution can buy complete products. However, if you are willing to make your own box, I advise you to give it a try. That way, you will be able to make the exact right box for your generator, with precise measurements and all the necessary features. On top of that, it is a straightforward process that doesn’t require any technical expertise.
This box simply needs to be placed around your generator to do its work. As long as your soundproof generator box has the appropriate venting ducts, you don’t need to think about it at all. In fact, you won’t even remember setting it up while still enjoying the refreshing peace and quiet.
Without further ado, here is my guide to making your own soundproof box.
Tools and Materials
Before getting into any work, it is necessary to be properly equipped in terms of both tools and materials.
Which tools do I need?
Here are the tools that are needed to make the soundproof box quickly and as described in this guide (but you can use any other adequate tools that can do the work):
- Measuring Tape
- Compound Miter Saw (like Hitachi 15-Amp 10″ Compound Miter Saw)
- Drill/Driver (DEWALT 20V Compact Drill Driver)
- Level Tool (Stanley Tools 24″ Box Level)
- Oscillating Multi-Tool (DEWALT 20V Li-Ion Oscillating Multi Tool)
What about the materials?
You can used the following materials:
- Three 3’ x 5’ panels of lightweight tile backer board (consider the USG Durock Brand 3’ x 5’ Backerboard Sheets or other tile foam backer boards)
- Three 2” x 2” x 8’ furring strip boards
- Soundproof insulation (Owens Corning Fiberglass Boards)
- A can of high heat spray paint (like Rust-Oleum 12-Ounce Heat Spray)
- A handle (Lizavo Pulls in Black)
How to Make a Soundproof Box for Your Generator (Step-by-step)
Obviously, generators come in different shapes and sizes. That s why the first step to building a soundproof box is to measure the generator. Make sure you don’t take this step lightly as you’ll end up with a box that won’t fit (I know this first hand).
When you have taken your measurement, put them down on paper and don’t forget to add a few inches on all sides.
Next, take the measurements of the generator and cut some furring strip boards to create a frame for the box. I started by making two sets of legs from the strip boards, which were a few inches taller than the generator.
Following that, I cut a couple of small blocks from the furring strip boards. Then, I screwed the small blocks onto the two adjacent sides of the central section of each of the legs. These small blocks are for the inside panels.
Afterward, I screwed together each separate pair of legs with a top plate, with the small blocks for the panels facing each other (and the generator). The purpose of the side panels is to hold the box together. Then, I measured the distance between the leg frames.
I used a lightweight foam backer board to create the panels for 5 out of the 6 sides of the box (leaving the bottom side open). Namely, I cut the inside and the outside panels according to the measurements I took from the frame. I screwed the outside panels onto the frame of the box. Following that, I used the small blocks to screw the inside panels onto them. The space between the outside and the inside panels was equal in size to the width of the small blocks on the sides of the legs.
As a result, I got a double-paneled box with the bottom side open. I stuffed the cavity between the inside and the outside panels with lightweight insulation. Following that, I turned the box so that the open bottom side was facing up, and I cut my cheap insulation into sheets. I then stuffed the cavity with the sheets.
Once that was done, I capped off the bottom of the box with the 2’’ x 2’’ furring strip boards. That way, the insulation was safely sealed between the inside and the outside panels.
Afterward, I used my oscillating multi-tool to cut out a channel for the exhaust pipe. That can also be done with a regular jigsaw.
Once the box was constructed, I painted it the color of my choice using a can of high heat spray paint.
When the paint dried, I installed a handle to make the box portable. I screwed a small block of the furring strip board on the inside of the top-side panel to serve as backing for the handle. Then, I screwed on the handle in that same spot, but from the outside.
Afterward, I installed an extended exhaust pipe on the generator. The channels I had previously cut out for the pipe and the cords to go through were now in use. The finished box is open on the bottom side, and I use it by placing it over the generator. So, the channel should be wide enough for the long exhaust pipe to go through.
Before finishing up, I cut out an opening at the location of the pull string. The purpose of that opening is to draw in cool air from the outside and to push the hot air away from the generator. That way, I made sure the generator wouldn’t overheat inside the box because airflow is crucial for the functioning of the generator.
Finally, to further improve the level of acoustic insulation, I added a small exterior piece on the inlet. That piece was angled at 45 degrees and would serve to direct the sound downward in order to improve the noise reduction qualities of the box.
Also watch this video tutorial:
Additional Tips for Your Quiet Box
- You can add a fan to the box for the airflow, as well as outlet access.
- As for the plugs, it is best to cut a square opening on the side with a latch that would accept the plugs.
- Using better sound insulation may produce better results. However, even regular and affordable store-bought insulation will make a difference.
So, Should You Build It
You can make this soundproof box for any portable generator. People who often take their generators camping can easily bring the box with them or build one on the spot. It doesn’t weigh much since the materials used for the construction are lightweight. The difference in noise levels you can achieve with this box is instantly noticeable. Just make sure you create proper airflow to avoid overheating and consider making further upgrades by adding a fan.
All things considered, I recommend making your own soundproof generator box because it’s a great way to save money and avoid buying a similar premade product.