Sound proofing for the interior

[Henrik]

I am about to order an entire new carpet set for 1283 and before I install it I am planning on sound proofing the interior.

Questions:
1) What maker of soundproofing material is preferred? I believe there is Dynamat - who else?
2) What interior surfaces should be sound-proofed and which ones are unnecessary to cover? One area I am wondering about are the wheel houses: Do the sound-mats generally glue down well on convex shapes? (I mean the carpet will have to go on top so the sound-matting can not be wrinkled, right?).
4) How much sound-matting is needed (sq ft etc)?

Henrik

[QuadcityDMC]

When I replaced my carpet I did not put an sound proofing in. There was someone on the old site that had used the dynamat. I don't think he has post about his findings. I have heard after putting the dynamat in that you might be able to hear the body tube harmonize and you'll hear an odd sound.

I used DMCH carpet set and was afraid of putting the mat in because of possible fitting issues.


I did install a sub in the car and I can not hear the engine or out side noise and I'm not blasting the stero. I wounded if my subs frequency is in tune with the car and is canceling out the noise.

[David T]

You can't go crazy with Dynamat or anything like it. It works well but it is very heavy so if you cover everything you can add a LOT of weight. BTW it also helps keep the interior warmer in the winter and cooler in the summer.
David Teitelbaum

[jawn101]

I used an off-brand to do mine instead of the much higher priced Dynamat. Do the floors, footwells, transmission tunnel, rear firewall and the triangle section between the electrical and engine computer compartments. The rear wheel wells are probably worth doing as well but I didn't.

The properties of the matting are such that it will stick and perfectly form to whatever surface you're working with. It will not wrinkle or bubble or be at all difficult to adhere. Just make sure that the fiberglass surfaces are very clean and very dry (vacuum out well, then use Scrubbing Bubbles or Oxy Kaboom to really clean the surface) before adhering. You will have to scrape the old padding off, and it will be a huge mess. May take you a few days to get it all done. Pull up what you can, scrape it lightly with a putty knife and vacuum up the debris between rounds. Spraying the remnants with Scrubbing Bubbles will dissolve the glue and let you scrape it up a lot easier.

Have a roller handy to make sure you work out any air bubbles under the matting and get maximum adhesion. The mat material is a bit of an enigma temperature wise. Much easier to cut when cold, but a lot harder to install. When it's warm, your knife/scissors will bind up in the slightly gooier adhesive, but the material will stick a lot better. Best is to do it when warm and have a very good, sharp utility knife with a lot of replacement blades handy.

Some photos are attached. Word to the wise- don't cover the area where the seat tracks run (between the mounting studs) - this will cause the seats to be very hard to move back and forth. I still have to go back in there and cut the matting out of that area. Also, be sure to carefully cut holes around any bolts. You can see examples of this in my photos.

If you're doing new carpet it will have new padding underneath. You'll need something to replace the padding on top of the rear Y. I just used standard stain resistant carpet padding, available at any home improvement store. In fact, the piece you need is so small many stores will have scraps laying around they will give you for free.

[TTait]

lots of info here:

http://dmctalk.org/showthread.php?439-New-carpet-soundproofing-and-dynamat-any-tips

[dmc6960]

A lot of people say to use the cheaper stuff, but I emplor you not too. When it comes to dynamat, stick to dynamat. Almost all other cheaper alternatives are asphalt based, which will break down and fail after a few years. Dynamat (extreme) is butyl based and will not.

Also not dynamat alone is not a complete soundproofing solution. It significantly reduces panel resonance but does not block sound all that well. To do that you need a loaded mass damper decoupled from the panels they are attached to.

[john 05141]

I commented in the other thread so I have the Dynamat. I think such "so called sound proofing amterial" is not worth it.
Add foam behind the cargo wall, THAT makes a difference;, Find out what makes the most noice, the engine or the road noise. If it is the engine, your area to improve is behind the cargo wall.

John

[Henrik]

Thanks everyone - great input y'all!