I was wondering if styrofoam would work as a good sound insulator or is it just a thermal insulator? I started to sound dampen the car with Raammat, bedliner, expanding foam, and the like. I was working on the doors when I noticed it was just a hollow cavity. So far the rear door is Raammatted and sprayed with bedliner. I was thinking of filling in the hollow frame with packing peanuts in a plastic bag. Is this just another lame idea?

 

Yes foam does absorb sound better than raammat and the like. Those products are good at killing vibrations and thats pretty much it. Styrofoam I guess would work, but I havent used it. A couple of us have used carpet padding from Lowes or Home Depot and it does make a nice difference.

 

Kevin,
I have done what you mention using large zip-locks and polyfill or owens corning myraflex. But not in the doors because of the window that needs free space within to move. My rear fenders are stuffed with myraflex.

 

thanks guys for your input. I'll get to work on this soon.

 

What kind of Styrofoam you use?? where to get??
So, do you open your door panel and stuffed it with styrofoam and spray it with bedliner??

They sell some kind of spray chemical at autozone and claimed to reduce the road noise, is that really works?

I really want to reduce my 95 GLE's road noise.............so please help..............

 

If you read my post above you will see I didn't use styrofoam. But if you want the equivalent in the doors continue reading. Go to home depot. Get one 4X8 sheet of foam board insulation. Cut a piece to fit below the steel beam in the door and one to fit below. Now cut horizontal strips half the thickness of the foam board. These strips will allow it to bend. Spray the sheet metal and the foam with spray adhesive and attach. Personally I would use at least one layer of a quality damping material before applying the foam.

 

Will it interfere w/ power window?
and what kind of quality damping material that you suggested?

Thanks a lot, I'll try it later.....

 

If you adhere to the outer door skin it will be at least a couple inches from the window path. The steal beam is at least 1 inch diameter.

Common damping materials:
Cascade audio mass loaded vinyl
Dynamat
Raammat
Lowes carries a roof flashing material with viscoelastic rubber adhesive, by far the cheapest
Driveway Medic
www.Gasolinealleyllc.com
www.technifoam.com - mass loaded vinyl barriers

 

I opened my door panel and It already has styrofoam in it.....
do you think I should install more sound insulation?

Does it usually come w/ styrofoam in the door panel?
fyi, mine is a GLE

 

If you look carefully that styrofoam is only 9-12 inches wide and only on the bottom half of the door. You want to install foam that covers the entire panel.

 

If you have ever seen the "eggshell" foam that's used to place on top of bed mattresses to make them softer, you can use that. If kind of looks like the bottom of an egg carton with all the grroves and dips in it. It is foam padding and will work great. That's what I used to do my doors and it worked amazingly well. Same method as mentioned above. Cut to fit, spray on adhesive and press and stick.

 

Actually the mattress pad is what I use, and less than $10 for the whole pad at walmart

 

That's exactly what I am talking about. I bought mine from like a Dollar General store for $7 or so for a twin bed size piece. You get a low of stuff for the amount you pay. It works really well.

 

If you install egg shell foam inside the door, it will fill with moisture and rot or fall off. Or am I wrong?

 

I really think that it depends on how much you use your windows. I sprayed scotch gaurd on mine, but I hardly use my rear windows at all. I just had to make sure that the front ones were properly coated.

 

The water will drain more slowly out the drain holes, but will still drain. I have't had any excess water problems.