Octavia Wagon sound deadening

[wfdTamar]

Dynamat Extremed my boot on the weekend. Did complete coverage of the whole floor, spare wheel well and wheel arches, quite a lot of the panelling behind the boot side panels (maybe 40-50%) and the rear panelling under the tailgate. Also about half the width of under the rear seats (so far). Haven't done the tailgate.

Used 8.5 sheets! I reckon if you only did the 25-30% coverage you might get away with one 9 sheet pack for a whole car, but for the sort of coverage I did needs at least 2 packs, if not 3 if you're also doing the doors. What I got was the older black (with silver logo's) stuff and it's really hard to see things on it so get the sliver, if not a different brand that doesn't feel the need to plaster their logo all over it.

Here's some photo's showing the stripped car with just the factory applied sound deadening, how much Dynamat I put in (and how terrible it is to find things dropped on it), The rear door speakers and door undressed.

Untitled | Flickr - Photo Sharing!

(Photo's now in posts below)

A few tips - Apply sheets from a centre line down the car, not from one side to the other. That way it's symetrical and once you've cut a sheet from one side it's easier to work out how to cut the mirror side one. For a really neat finish use the Dynamat finish tape on joins since the edges of the sheets ooze butyl and it gets on your clothes when you kneel on it. I used one roll just in the boot.

I did each of the 7 sections of the spare wheel well walls with a seperate panel of Dynamat as there is a compound curve at the top edge. I only left the central bit (about 50mm in diameter) of the spare wheel well free of Dynamat.

I was considering some 1/4" Dynaliner as well, but this is really getting pricey and I reckon the whole car floor would use about 4 packs of it!

I'll take after photo's when I put my stereo upgrade in and sound measurements when I've gone for a drive.

When you take the door panels off you will inevitably break the plastic clips holding it on. Here's they type they are:

http://www.ebay.com.au/itm/160968028...84.m1439.l2649

[wfdTamar]

Getting another 2 packs of 9 sheet bulk packs of Dynamat Extreme and 4 packs of 1/4" Dynaliner - sodding car better be quiet and cool enough to sleep in after this.

A box of Dynamat Extreme (9 sheets) weighs 7kg (that's just the sheets, not the box).

[wfdTamar]

I used 2 boxes to do the whole car (tailgate, wheelarches, complete floor through to the firewall, firewall about 300 mm up), except the doors, which I reckon will take 5-6 sheets.

[bobski]

How are the results?

[wfdTamar]

With just the boot done (and rear wheel arches), not any notable difference measured with a sound meter, but it's definitely quieter from the back. I now notice the noise at the front more (front tyre noise, wind around mirrors).

I drove it with all the interior out of the main compartment and the floor done with Dynamat and then noticed how much noise comes through the doors (it's like renovating). Under the carpet there's about 25mm of cotton wadding underlay which does a fairly good job and dense foam rubber at the firewall. If you wanted to do a really good job you'd replace the floor wadding with Dynapad (the heavy one).

I won't be testing it with just Dynamat Extreme and all the interior back in - I'm putting in DynaLiner (this is more for heat than noise).

Doing the door inner skins too - at the same time putting in a fancy Polk Audio upgrade (speakers, sub, amps & processor)

Planning a nice audio upgrade for RNS510 in Octavia


I've used 2 whole 9 sheet packs on the floor and each door takes a sheet.

[brad]

How much weight would all this be adding?

more photos required

[wfdTamar]

Ok, try again with bigger photo's.

Each box of 9 sheets of Dynamat Extreme is 7kg. The Dynaliner weighs hardly anything - each 810 x 1370mm roll is 500 grams.

I used Flickr for photo's before. It's just far easier to go from iPhoto to Flickr, but here they are below.

Here's the interior stripped prior to installing Dynamat. You can see there is a reasonable amount of factory deadening.

[wfdTamar]

Some more:

That's one of the sheets you get in a Dynamat pack.






This is the quite dense foam rubber that's at the firewall.

[wfdTamar]

Some more:


That's the underneath of the firewall rubber you can see.




The rear door. That aluminium plate is riveted on and has a foam gasket. It seals quite well, but on the front door ones I put one screw in outboard of the speaker hole.




I put these in so you can see where the panel clip points are. Virtually impossible to remove the panels without breaking the clips as they're very brittle (and even some of the mount points for the clips on the panel can break). You'd want to get some new clips before you start.

[wfdTamar]

Here's the type of panel clip:




After Dynamat Extreme. I went for pretty much complete coverage, but apparently you get close with 30%, as it's not so much noise blocking as vibration absorbing.

For noise blocking the heavier Dynapad is best and that really needs to be laid over the whole surface to work. It is 1/2" thick though, not peel and stick, or as flexible as Dynamat Extreme and Dynalayer and weighs 1 pound per square foot (don't know what that is per square metre).