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OT: Thermal sound/heat deadening blanket material recommendations

Dumpster_diving

Cast Iron
Joined
May 18, 2017
Location
Massachusetts
I'm constructing a weather enclosure to house a portable Honda 5000W backup generator. I am aware that ventilation and heat management are a concern. The shed will be sized appropriately larger than the generator and with several 12v fans and vents to force-move heated air out of the box.

As an additional precaution (heat and sound) I would like to line the inside of the shed with foil-faced, adhesive, engine compartment foam sound/heat shield.

I'm seeing multiple products on Amazon and Ebay. Most seem to be in the $40/square meter price range. My application would probably require close to 7 square meters +/-. That's getting a bit pricy.

Any recommendations for a specific product/manufacturer that might be available in larger sizes (or at slightly less cost for multiple rolls)?
 
Thanks Rob,

I hear you about the ex5500 being very quiet. I have heard very good things about the ex5500.

Regardless, the one I have- a gently used EM 5000 SX- is a significant upgrade from the one I had been using previously, a Coleman Powermate 6000.

I got a rocking good deal on the EM 500 SX (sub-$1k) and it fits my needs quite well (110/240v, electric start, remote start on a 50' pendant, etc.). So I'm committed to sticking with this one for now.

Goal is simply to weather/theft proof it and (to the extent reasonably feasible) take the decibels down slightly with the enclosure and the foam.
 
Thanks Doug. I think that would do a lot for the sound level and couldn't be cheaper or easier to install. But my instinct is that standard ceiling tiles aren't particularly inflammable. I'm doing my best to provide clearance around the hot parts but it is still a constrained space- essentially a 4x8 engine room.

The 'dumpster_diver' in me would love to consider ceiling tiles (or even Home Depot insulating foam board)...but I think the better part of valor is to seek something foil-faced and ideally specifically designed for an engine compartment.

Like the kind of foam sheets they use in marine applications.
 
Thanks Doug. I think that would do a lot for the sound level and couldn't be cheaper or easier to install. But my instinct is that standard ceiling tiles aren't particularly inflammable. I'm doing my best to provide clearance around the hot parts but it is still a constrained space- essentially a 4x8 engine room.

The 'dumpster_diver' in me would love to consider ceiling tiles (or even Home Depot insulating foam board)...but I think the better part of valor is to seek something foil-faced and ideally specifically designed for an engine compartment.

Like the kind of foam sheets they use in marine applications.

How are foil faced foam boards any less flammable ?

marine rated ? Jesus the price just shot up.

Try making a panel with another spaced 2" above it, and holes into the center section
"Helmholtz Resonator" IIRC
 
Rock wool or mineral wool is what you want. Fireproof and meant used for sound deadening. I have seen fiberglass glued inside furnace enclosures also. Good luck lighting that on fire.
 
Rock wool or mineral wool is what you want. Fireproof and meant used for sound deadening. I have seen fiberglass glued inside furnace enclosures also. Good luck lighting that on fire.

Good suggestion. Roxul is one brand. You can get it in batts or denser more board like variations as a replacement for rigid foam insulation.
 
Thanks all. Rock wool makes sense. I've used that for fire-blocking in stick-frame construction in the past. Should provide more than sufficient sound deadening and the price is right.

Appreciated.
 
Your biggest problem is all those fan and vent holes. A comparatively small hole pretty much swamps all the soundproofing you do in the closed areas. This is due to the log nature of Db's and our subjective assessment of loudness.

You might baffle any fan or vent hole so it doesn't get direct sound, then tube it outside with a rock wool lined tube. Rock wool on the inside can also reduce higher frequency reflections. Take care to consider rain and those holes, as well.
 
I used stable mats to quiet a deetroit diesel. Worked very well and cheap. It's 3/4" thick rubber, recycled from car tires. It cut the noise in half, measured. Cost about $40 for 4' x 6' mat including tax. Heavy as hell, about 100 lbs for the 24 ft2 -- but that's what you want. Mass damps noise. You can get them easily, check out feed stores first (although mine came from the local Tru-Value, but I think because the store owners had horses.)

If you're building the shed yourself, check out the sound booth forums for recording studios. Lots of simple things you can do to make sure there are no noise short circuits, such as not having the walls connected to the same studs on both sides. Offset them with an air space. Plain old sheetrock, two layers thick, is also a commonly-used (and cheap) method.

The expensive cool and groovy stuff from JC Whitney doesn't work all that good.
 
mass, airspace, mass.

fuzzy stuff just reduces reflected sound (you do need to do some of that also, but to reduce transmission it's mass you need). no mystery here.

for outdoors, avoid drywall!. use tile backer (cement) board, or as billD said, concrete (don't bother with 100% gaskets though if you have other openings). mineral wool should be well enclosed, or critters are going to make it home, or take it home.
 
If you value your time, you might consider selling your generator, saving the time and costs of the hut, and getting a 7000 EU is, which is really quiet. Really quiet -- like you can have a reasonable conversation right next to it. Get a big doghouse to put it in for weatherproofing, and call it done.
 
The walls and ceiling of the box will transmit noise through the walls unless they are too heavy and dense to vibrate and act like a drum membrane.
The concrete block with cast concrete ceiling would work.
Consider a heavy plywood wall, with multiple layers, of concrete 'green-board' drywall, each separated by 1/2" spacers [plywood or OSB strips]. Multiple dense layers will prevent transmission of noise.

Make air passageways a labyrinth design. no straight lines and multiple angles or turns, Air will make it through, but noise energy will bounce a few times and die. Especially if the reflective surfaces are soft, not reflective.

DualValve
 
Keep it cheap.

Just divert the sound away from where you/family are. Let distance attenuate it, thereafter.

Simple one-plane barrier can do that. Logs are good. Earthen berm or bandsags, better-yet. Roof or other walls are then less critical.

Otherwise, it keeps bouncing around until it FINALLY all downshifts to heat.

Disclosure: MEP-803A, NATO "Tactically Quiet", here. What it takes to make it quiet is not cheap.
Liquid-cooled 4Cyl Lister-Petter Diesel, 1800 RPM, perforated metal panels with a bit of mass, elastomer mounts, absorbent fiber mat. Foam seals. Labyrinth air passages. All-metal enclosure.

Find the info online (there are full manuals), copy what you can copy.

Get payback off your tax dollar R&D spend instead of trying to re-invent a wheel they spent BIG coin chasing.

12 KVA worth
 
I have worked around the whisper watt generators, not the studio ones but the next ones down, and the foam inside isn't more than a 1" thick but the diversions on the fan intake and the exhaust is where most of the sound suppression happens and is needed. get above one of those and sound levels go up quite a bit.. but I have left the site with those still running because Im deaf enough I couldn't hear it. thought I had shut it off.
 
I have worked around the whisper watt generators, not the studio ones but the next ones down, and the foam inside isn't more than a 1" thick but the diversions on the fan intake and the exhaust is where most of the sound suppression happens and is needed. get above one of those and sound levels go up quite a bit.. but I have left the site with those still running because Im deaf enough I couldn't hear it. thought I had shut it off.

I "grew up in" a pair of anechoic chambers, one of America's most competent hearing aid makers, last was around this "stuff" as Project Manager, Salon Films, HKG - their first Digital Multi-Media Studio.

The "upper bound" as to what can be spent is a HIGH bound.

NATO/OTAN had a pragmatic need for value-for-money, or "picking the low hanging fruit", most bang for the buck. That is far the better example to copy. Also fireproof. Also sore DURABLE.

Also mold & mildew proof. Try THAT with yer Funk & Batting!

Better-off to "green glue" rock-on cement board into a sandwich, sheet elastomer gym/exercise room goods the "meat" of it, then "rib" that with 2" X 4" PT softwood, shoji-screen writ large style, and "face" the business side with elastomer roll-stock or roll roofing with grit in the "cells".

Anything more effective starts getting to be a mess, with critters wanting to live in and on it.

You can appreciate why I just BOUGHT the damned MEP-803a, turnkey?

:D
 








 
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