Generator Quiet Box and Other Ways to Reduce Generator Noise

The constant hum of a generator at night can be very annoying to some! Luckily reducing the noise from your portable generator is easier than you think, with just a few simple steps you can rest soundly next time you are camping or RVing. Not only will it help your sleep, but a quiet portable generator also makes for happy neighbors and won’t scare away wildlife. A generator quiet box and other generator box options are the first thought, but there is so much more to help noise!

All generators produce some noise – typically a buzzing noise – in their motors, which carries out through the exhaust pipe. The biggest bang for your buck is figuring out the best way to decrease the sound from the exhaust.

A great metric for determining how loud a generator is is by using THD. This stands for total harmonic distortion and we’ve created a helpful guide to show our 3 favorite low thd generators.

Sound is not linear, but logarithmic – meaning a 10 decibel decrease in sound, is perceived to be a 50% reduction! Good for us, the small steps we take to reduce sound will make a world of a difference!

Below are the most effective ways to reduce noise on your portable generator with estimated impact:

Buy a quiet generator – High noise reduction

If you are looking to reduce your generator noise a large amount – you should first buy a quiet generator – most likely an inverter. Check out our top quiet portable generator pick.

Its worth noting that 1) large generators create more noise, and 2) all else being equal inverter generators are quieter due to the more advanced technology used.

Build a generator quiet box – High noise reduction

It is really easy to build your own DIY baffle box or generator sound box. You want to enclose the generator with a DIY sound box to lessen noise. The trick is making sure that your generator does not overheat and at the same time you have easy access to the power cord while in use. 

Unfortunately there are not many pre-made baffle sound boxes on the marketplace. Roll up your shelves and head to your local hardware store to make your own in a weekend afternoon. If you find yourself in a pinch, a ready made weather cover can do a nice job.

Check out the video below to see a custom system.  This DIYer put together a very impressive set for his inverter generator (a Honda EU2000i).

We’ve also written a helpful guide on building or buying a portable generator shelter to keep your generator safe from outdoor elements.

https://www.youtube.com/watch?v=Dfts_oJifJs&t=48s

Add a muffler to your generator – High noise reduction

If you are handy with welding and mechanics you should check out the video below. This DIYer added a muffler to his generator to reduce noise. Mufflers are premade to reduce the noise of a car, so logically installing one on your generator will have the same impact. Consult an expert before doing this yourself though!

The video below shows a homemade muffler attachment that reduced the noise on his generator.

https://www.youtube.com/watch?time_continue=262&v=tvipXohjpX0

Water absorption – High noise reduction

A very simple way to reduce noise involves a hose, water, and bucket! Attach one end of the house to the exhaust of the generator and then put the other end of the hose in a bucket of water. To prevent a fire, be sure to use flex tube made of galvanized metal (NOT A RUBBER HOSE)

The sound goes through the hose and is muffled by the water. Of course, keep your generator away from the water.  Also make sure to add a small hole to the hose at the high point.  This lets air flow in the hose preventing any air pressure to build up. This keeps water from sucking back into the generator and possibly ruining it!

Rubber absorption – Medium noise reduction

If your generator is sitting on something hard – say concrete – it is going to make more noise as the engine runs and the unit shakes a bit. Placing your generator on something soft (think rubber mat) will dampen the noise caused by vibrations. If you are out camping or RVing, then try to find a nice soft patch of ground.  Dry soil can create a lot of noise, so for this situation a rubber mat works nicely.

Plywood boards – Medium noise reduction

Plywood boards are a cheap and easy way to dampen generator noise. Just lean 2 or 3 around your generator to reduce the noise. Be sure you are not blocking the exhaust and airflow and make sure no plywood boards are leaning against the generator. Try to build a box or triangle around the generator without touching.

If you would like to purchase something more substantial and pre-made – check out the Quiet Fence below.

Redirect exhaust pipe – Medium noise reduction

Sometimes simple solutions can help a lot. By positioning the exhaust pipe of your generator in a vertical position, the sound is redirected upwards, greatly reducing generator noise. Pointing the exhaust (and the noise) up into the sky works well to lessen noise when camping in an open space. The sound moves up and disappears into the sky!

Move the generator away from the campsite – Medium noise reduction

This is an obvious statement – moving your generator away will also reduce noise (big surprise right). With a long extension cord you can target 50 to 100 feet away.  Be friendly to neighbors and make sure you aren’t creating more noise for anyone else! As annoying as a generator sound can be, its even more annoying when it’s not your own!

Wrap it up!

After going through the top ways to reduce generator noise, here is what I would do.  First buy a quiet inverter generator to make your life easier.

If you already have one, then head out to the hardware store and cut plywood to make your own generator quiet box.  Buy an extension cord (preferably 100 feet), then place your generator far away from your campsite, inside the box, with the exhaust pipe pointed to the sky. 

Not the most flashy method but it works great and makes a big difference!

About Chad & Rick

Chad and Rick are the father son team behind Generator Hero. Rick is an engineer and manager, he’s used generators his whole life and specializes in fact checking our articles. Chad is a writer and webmaster helping to keep things running smoothly on the site. Read more about Rick and Chad, or send a message using this contact form.

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