How to Quiet a Generator

How to Quiet a Generator with a DIY Generator Enclosure

How to Quiet a Generator with a DIY Generator Enclosure

Whether you operate a mobile business, are an avid camper, or just like to be prepared - a portable generator is an extremely useful machine. But as useful as generators are, they’re pretty simple contraptions and aren’t built to be sleek or quiet.

We often talk about how soundproofing your vehicle can make for a more comfortable and enjoyable car ride, the same can be said for your camping trip or business. Roasting s’mores around a campfire is definitely more enjoyable without the roar of an engine in your ear.

Let’s go over some tips on how to keep the noise down when using a generator, as well as creating a sound enclosure for your generator.

Whether you operate a mobile business, are an avid camper, or just like to be prepared - a portable generator is an extremely useful machine. But as useful as generators are, they’re pretty simple contraptions and aren’t built to be sleek or quiet.

We often talk about how soundproofing your vehicle can make for a more comfortable and enjoyable car ride, the same can be said for your camping trip or business. Roasting s’mores around a campfire is definitely more enjoyable without the roar of an engine in your ear.

Let’s go over some tips on how to keep the noise down when using a generator, as well as creating a sound enclosure for your generator.

Memorial Day sale
Memorial Day sale

Popular Generator Box Soundproofing Materials


Luxury Liner™ Mass Loaded Vinyl (1 lb / 2 lb)
Damplifier Pro™ Deadening Mats
Mega Block™ Insulating Heat Shield

Quick Tips to Make a Generator More Quiet

  1. Get the right size - The more powerful the generator, the more noise it makes. Assess your power needs and stick to a generator that gives you the right amount of power. This will reduce excess noise.
  2. Point the exhaust away - Make sure the exhaust is pointed away from where you’re located, or even straight up. This will help the sound dissipate.
  3. Keep your distance - Put the generator as far away from you as possible, ideally a minimum of 20 feet. Invest in extra-long, heavy duty extension cords.
  4. Stick to soft ground – Hard surfaces like concrete or asphalt will strengthen the reverberation and increase the noise. Placing the generator in grass or dirt will keep the vibrations down. You can use a rubber mat if you’re unable to find soft ground.
generator on soft ground at campsite

Although these tips can help you reduce the noise somewhat, ultimately the generator is still exposed and will still be noisy. The best thing you can do to make your generator quieter is to add an enclosure. If you already have one, we have some advice on how to help make it quieter. If you don’t already have an enclosure and are interested in creating a generator sound box, skip ahead.

Soundproofing Your Existing Generator Box

Ok so, 100% “soundproofing” isn’t quite possible. Normally when we talk about soundproofing, we suggest to completely cover and enclose the space you’re attempting to soundproof. For safety it’s extremely important to leave lots of ventilation and room for airflow. This means you can’t eliminate the sound completely, but you absolutely can reduce it a great deal and bring the noise to a much more comfortable and enjoyable level.

Stopping Generator Box Vibrations

If you feel like your generator box is creating a lot of noise due to vibrations, you should start with a sound deadening material such as Damplifier Pro. This usually occurs if the walls of your generator box are made of metal, but Damplifier Pro will also reduce vibrations in a fiberglass or plastic container.

metal generator box by a house

Blocking Sound From Escaping the Generator Enclosure

Next up apply some mass loaded vinyl. Our Luxury Liner MLV is an excellent noise barrier and is an absolutely key material for any generator box. It comes in two densities: 1 lb per square foot and 2 lb per square foot depending on how beefy you want your barrier to be. The MLV will help to actually block the sound waves, greatly reducing the noise of your generator. For MLV to be effective be sure to cover 100% of either the (preferably) exterior wall of your generator box. You can do interior, but only with plenty of heat protection for the vinyl. The only gaps should be for wires or exhaust. Then seal the edges with foil tape or acoustic caulk to make the seams airtight.

Reducing Heat From Your Generator

If you’re worried about the heat coming off of your generator, consider an insulating material like Heat Wave Pro or Mega Block. Remember that adding layers adds thickness. Your generator needs space and airflow for safety and efficiency. Be wary of typical foam products as they usually have low-heat resistance (less than 200 F) and won’t hold up against the heat of the generator. Always tape the edges of any heat insulation material you use with foil insulation tape.

Building Your Own Soundproof Generator Box

Although you can buy generator boxes, we’ve found that they can be pretty expensive for something that's not too hard to DIY. If you’ve got a few tools and a couple of hours, it can be much more cost-effective to build your own. All generators are built differently, so we can’t tell you exactly how to build a box for your generator, but we’ll teach you principles and strategies that will guide you while you’re building your new generator box.

Dimensions and Size

Generators produce a lot of heat, so it’s important to account for adequate airflow. Be sure to add extra height and width, you don’t want the generator too close to the walls of the box as it can damage it and your generator. Consider the additional insulation and soundproofing layers you’ll be adding, as they will add thickness to your box. Finally, be sure to measure cutouts for the exhaust, and to run cables from your generator.

Materials

Frame your box with wood, simple 2x2’s or 2x4’s will work fine. For the paneling consider a lighter, flexible material such as fiberboard (MDF). You can use plywood if you’d like but it is heavier and stiffer, so it will make the box harder to move around. Absolutely stay away from metal for the walls or frames as it will rattle and create more noise. If you do use metal, plywood, or a stiffer material, couple it with Damplifier Pro or Spectrum to reduce rattling.

Insulation

If you’re concerned about the amount of heat coming off your generator, you can try insulating your generator box. The best way to do this is to create panels with a space between them as your walls. In this space you can insert a Class A fire rated insulating material like Heat Wave Pro (jute) or Mega Zorbe (high heat open cell foam).

Soundproofing

Generators are engines - loud, rattling, mean machines designed to do one job really well. Adding a mass loaded vinyl material will do wonders to block the sound from your generator and keep your area quiet. Our Luxury Liner is only 1/8th in thick and comes in easy to manage sheets for you to cut to size. We recommend installing the material to the exterior walls of your generator box. Be sure to cover the walls edge-to-edge and adhere it firmly with a vinyl contact cement, nails, screws, or staples. Tape the edges with foil tape or use an acoustic caulk to ensure the seams are airtight.

Exhaust and Ventilation

Not creating adequate ventilation for your generator is dangerous, and will ruin both your brand new generator box, and your generator. If you want to have a smaller box, you’ll need to add an extended exhaust pipe that can run outside of your box. If it’s a bigger box with more airspace, you can get by without one. You may be able to purchase an exhaust pipe specifically for your generator. If not, measure the size of your exhaust and use a material like copper piping that can endure the heat from the exhaust. Ensure that the pipe seals completely at the generator exhaust, as you don’t want fumes leaking and circulating in the box. Depending on the size and heat coming off your generator, you may want to consider cutting out additional ventilation windows.

white metal generator box with exhaust vents

Cooling

Some people add a fan to their generator box to help with airflow and cooling their generator. Remember that the space inside your generator box is small, so a tiny box fan will go a long way. Buy something cheap, sturdy, and ideally square. Cut a hole in your box to size and fit in your fan, use caulk to seal in the fan as well as fill in gaps. Make sure the cord is pointed inward, which you can just plug directly into the generator when in use.

You Did It! Now Your Generator Box is Soundproof

Ultimately generators are incredibly useful, but come with the cost of a constant loud, low rumble whenever they are in use. With some cheap construction materials, and a few soundproofing products from us, this is one DIY project you won't regret. Now you can make your generator more people-friendly and finally finish telling that story about the giant fish you caught around the campsite.

 

Check out all of Second Skin's soundproofing materials to set you up for success solving your sound issues!