Generator Sound Box and Other Ways to Reduce Generator Noise

The constant hum of a generator at night can be very annoying to some! Lucky for us, there are easy and efficient ways to quiet a portable generator while camping or using your RV. In addition to your own sanity, a quiet portable generator also makes for happy neighbors and won’t scare away wildlife.

Most generators produce the most noise – typically a buzzing noise – in their motors, which carries out through the exhaust pipe. In order to quiet a portable generator, we must figure out the most efficient way to dampen the sound from the exhaust.

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:

  1. Buy the best quiet generator you can find (here are some examples) – High noise reduction
  2. Build a generator sound box – High noise reduction
  3. Add / modify a muffler on your generator – High noise reduction
  4. Water absorption – High noise reduction
  5. Rubber absorption – Medium noise reduction
  6. Plywood boards – Medium noise reduction
  7. Redirect exhaust pipe – Medium noise reduction
  8. Move the generator away from camp – Medium noise reduction

1) Buy the best quiet generator – High noise reduction

If you are looking to reduce your generator noise by as much as possible – you may as well start by buying the best quiet generator out there. Check out our top pick – quiet portable generator.

Also consider that 1) larger generators will create more noise, and 2) inverter generators are typically the quietest generators due to the technology used.

2) Build a generator sound box – High noise reduction

Building your own DIY generator sound box or baffle box can be as easy or as complicated as you want to make it. In general, the idea is to enclose the generator to dampen sound, while at the same time ensuring that it does not overheat and can provide quick access to power while in use. Of course, this takes a bit of time, energy, and effort so check to see if there are good pre-made options for your unit.  Most companies do not make pre-made baffle boxes, but you will find that their weather covers can do a nice job.

Chris from Chris DIYer put together a very impressive system for his Honda EU2000i inverter generator – check out one of his video series to see the nearly complete system

3) Add a muffler to your generator – High noise reduction

This is not something the average DIYer should take on, but just so you are aware, it is possible to add a car muffler to your portable generator to reduce noise.  Since mufflers greatly reduce the noise of a car, the same concept applies to a portable generator. Consult an expert before doing this yourself though!

The video below shows a DIYer greatly reduce the noise on his system.

4. Water absorption – High noise reduction

An old school DIY method for reducing generator noise involves a simple bucket of water. Attach one end of the house to the exhaust and then put the other end of the hose in a bucket of water. The best hose material to use is flex tube made of galvanized metal (NOT A GARDEN HOSE).

The sound goes through the hose and is muffled by the water. Be sure to keep the generator away from the water and add a small hole to the hose at the high point to prevent water from sucking back into the generator.

5. 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. Be sure to put your generator on something soft like this rubber mat to dampen the noise. If you are out camping or RVing, then try to find a nice soft patch of ground.  If the soil is too dry and hard, then a rubber mat is again your best option.

6. Plywood boards – Medium noise reduction

A cheap and easy way to dampen generator noise is to bring along a few plywood boards to simply lean and wrap around your generator while it is in use. Be sure you are not blocking the exhaust and airflow and make sure no wood is leaning against the actual unit if possible. Try to build a box or triangle around the generator without touching.

If you would like to purchase something more substantial and pre-made – the Quiet Fence below is another option.

7. Redirect exhaust pipe – Medium noise reduction

As simple as it sounds, changing the position of the exhaust pipe of your generator from horizontal to vertical helps redirect the sounds and reduce generator noise. When you are camping, pointing the noise up into the sky versus around your campsite works surprisingly well. The sound moves up and disappears into the sky!

8. Move the generator away from the campsite – Medium noise reduction

Pretty obvious one here but moving your generator farther away from you will also reduce noise. Make sure you have a longer extension cord and find a good spot 50 to 100 feet away.  Just be sure you aren’t creating more noise for any of your neighbors at the campsite or RV park! As annoying as a generator sound can be, its even more annoying when it’s not your own!

Wrap it up!

Now that you know the best ways to quiet a portable generator here is what I would do.  First if you are considering buying a generator and concerned about noise then purchase a quiet inverter generator.

If you already have a generator, I would pre-cut some plywood to make a nice box around your unit, buy an extension cord, and place your generator far away from your campsite, inside the box, with the exhaust pipe pointed to the sky. Not the most glamorous method but gives you the most bang for your buck!

Leave a Comment