sound insulation ideas for generator cover?

[ConnieH]

We are building a small metal silo to house our generator this year (7.5 feet tall, 5 foot diameter), and I'm debating different ways of insulating it in order to deaden the sound. Our first thought was standard fiberglass insulation, but I hate handling that stuff, so am looking for any suggestions, ideas, feedback, alternatives, etc. Other materials we've considered are:

~polystyrene panels - the plastic coated ones that are flexible & won't crumble if broken (too fragile for transport?)
~repurposed carpet padding (too flammable? too moopy?)
~repurposed comforters/blankets (too flammable?)
~Reflectix (too thin to be effective?)

Money is somewhat of an issue, but I'm willing to pay for something that will work with the least amount of hassle (within reason), and something that will transport well (i.e. take abuse). I'm also concerned about flammability - the silo will be vented top and bottom and will have plenty of room inside so that the gene isn't too close or touching any insulation material, but I still don't want a material that should it catch on fire, will STAY on fire and spread and create a 7 foot exploding fire bomb.

Are there any other materials out there you think might work?

[FIGJAM]

Google welding blankets.

[dragonpilot]

'SEARCH' is your friend...lots of info on this herein.

[jkisha]

We bought two 4' x 8' pieces of plywood, cut them in half and made four sided box. Then lined the box with old carpet. Worked like a charm. We're using it again this year.

An additional benefit was the entertainment value of people walking buy and not being able to resist looking into the box to see what was there! I think this year we are going to put something gory in the box along with the generator to give people a scare when they look inside.

JK

[gyre]

Look up movable insulation.

Fibreglas comforters are one approach.

Reflectis is a radiant heat insulator.
I doubt it does much for sound.

There are two approaches, isolation and absorption.
I recommend differential material layers for isolation.

[ConnieH]

Thanks for the replies...I've been doing some searching, but since this cover is a bit "different" being it's round and metal, I wondered if there were any materials I might be missing. We did the plywood box thing last year and it worked fine, but we wanted something that better fit our "Farm" theme this year. Does anyone think cardboard might deflect the sound up and out the top hole? We do have some 2" foam pieces that I may end up spray-glueing to the insides, that should absorb some sound.

[Token]

Back in the day where I had to determine the noise made by the electronics gear we were manufacturing, we contracted a speciality firm that had an anechoic chamber. It was basically a room with many layers of sound deadening stuff on the interior.

BASF makes a full regalia of products that fit the bill.

Sound recording studios are crafted in a similar way. Isolation and dampening.

Since you have some prefab metal gizmo you are using, a big challange will be deadening the resonance of the metal form. Dynomat has a good selection of dampers used in automotive application.

For sound absorption, open cell foam is best but any foam/sponge product will do for your application.

So, the steps are: 1. Damp the metal from resonating. 2. Attenuate sound with suitable padding. 3. Redirect sound that can't be dampened.

If you need to do this on the cheap, you can scavange many suitable materials that can get the job done.

[trystanthegypsy]

Egg cartons! You can definitely do some research on the engineering of recording studios, and/or google "how to make your own recording studio" and you will find lots of info.

Use maybe plastic sheeting to cover the inside? it might melt if it's too close to the geny but it shouldn't catch.

[much2naughty2]

Have you looked at Eggcrate Foam from foambymail, It's about 40 sq. ft. for $33 and comes in 12 colors. Orders over $75 have free shipping. Also since there is always a concern about the generator over heating, you might want to consider a 6-8" 120VAC fan, with a hole through the side of the silo. Fan will start with the generator, right.

since the size of the foam is 80" high, I'm cutting the box to 40" high and 4' x 4', lined with the foam. I was looking for a light weight product than plywood. Any suggestions?

[phil]

Here's the test: if you're not willing to have it running in your shade structure with you, it's too loud.

[ConnieH]

Have you looked at Eggcrate Foam from foambymail, It's about 40 sq. ft. for $33 and comes in 12 colors. Orders over $75 have free shipping. Also since there is always a concern about the generator over heating, you might want to consider a 6-8" 120VAC fan, with a hole through the side of the silo. Fan will start with the generator, right.

since the size of the foam is 80" high, I'm cutting the box to 40" high and 4' x 4', lined with the foam. I was looking for a light weight product than plywood. Any suggestions?

I have looked at foambymail, but for another purpose - padding for our Manchanical Bull Eggcrate foam would work, but I need 96 square feet, not including the top cone, probably another 15 square feet...looking for something a little cheaper. We are going to a regional event next weekend, I think I'll go with fiberglass insulation right now, and repurpose it in my garage afterwards. But for the burn...hmmmm... egg cartons may work and I will have the time to collect them - will bust out the few I have and start experimenting. I wonder if there would be a difference beween cardboard cartons and styrofoam ones...

If you are looking for something lighter than plywood, you could get some R-Max panels like I made my hexayurt from - insulating and light. About the same price, but they are hard to find some places. Or you could use thin paneling and polystyrene panels glued together. Oh, but you already have the eggcrate foam, correct? Glue that to thin paneling? You would need to stake it down good though since lightweight = blowing in the wind I've got several sheets of old paneling I'd give you if you were in Idaho! Paneling is pretty flexible, you might even be able to create a round shape with enough ingenuity and staking...might as well make it nice to look at, right?

[Elorrum]

Egg cartons! You can definitely do some research on the engineering of recording studios, and/or google "how to make your own recording studio" and you will find lots of info.

Use maybe plastic sheeting to cover the inside? it might melt if it's too close to the geny but it shouldn't catch.

egg cartons. I had a friend who worked at the dining commons in school and she collected the egg flats (about 1'x1' (36 eggs) from breakfasts for a number of days and made cubes of stacked cartons and then built a little hut. It was reeeeeallly quiet inside. This probably isn't a good idea for the silo shape (which I think is a very cool idea for a farm!) but has anyone used the drywall material called Quiet Rock?

[much2naughty2]

ConnieH, we do live close to ID. Where is the regional event?

[ConnieH]

ConnieH, we do live close to ID. Where is the regional event?

Near Twin Springs, past Arrowrock reservoir, just north of Boise towards Idaho City...Esthetic Evolution...it's next weekend! Tickets may be close to selling out, but it is a gooood time if you can swing it. About 1000 people, two big sound stages and many small sound camps, beautiful meadow above the Boise River. The silo will make it's first appearance there, and while sound isn't so much of an issue since we'll only run the gene at night (and hardly anyone sleeps at night), it's a good testing ground. Our gene will be quite a ways away from sleeping areas, too...mostly I'm worried about the noise reverberating off the metal, it's going to be much louder than wood (trying to stay on topic, hehe)....and seriously, if you come through Boise anytime soon and want to try the paneling, it's yours...

[much2naughty2]

We'd love to go ConnieH, but to short of time this year. We'll mark it for next year. Thanks for the evite