Soundproofing project

[pandkh]

Hi

I'm a new T25 owner as of a couple of months. I stumbled across the soundproofing thread on the wiki and after a recent day trip to the seaside, where the road noise was really noticable, I've compiled some bits together and I'm going to start tomorrow.

I've got £100 worth of Eastwood thermocoustic soundproofing and heat proofing material that I'm reserving for the boot and under seat. I also got 2 sq m of cheaper stuff on amazon for £20/m, eastwoods came out at just under£30/m2. Both were considerably cheaper than GTmat or Dynamat, which appear to be market leaders. This whole area is new to me.

I'm not sure I'm going to the extreme lengths of the wiki post but I'll do a reasonable job. Will make a video beforehand so that I can reference the improvement. First areas to target are boot and underseat. Roof, ie under the bed on my fixed hardtop, sliding door and behind the fridge. When I had the fridge out to put in the electrics noticed a bit of rust in the joints so have also got some eastwoods rust encapsulation so I'll give anything that needs it, a coat of that before putting on the sound deadening.

Has anyone else had a go at this and can give me any tips beforehand.?

Thanks
Pete

[spdbrd]

Hi pandkh,
I looking forward to future posts as I too thinking of this.
For what it's worth I thought of front bulkhead, under seat and above wheel arches also behind units at basically it's a big resonator behind those units, and above and around engine comp.
Like i say not done it yet but is on that mythical list the wife sees me putting together while on the internet!

Good luck

[Winchweight]

A lot of the T4 guys use flashing tape. It's a fraction of the price of the proper stuff, but works a treat. Cover the wheel arches and cab floor with it, then put some on all the sidewall panels to combat the drumming effect and the difference is noticeable.

[pandkh]

An update on progress.

On saturday I emptied the van, took the floor up in the fixed high top, and sound proofed both roofs, under the rear seat and the boot/load area.

I used the cheaper soundproofing material off amazon for the overcab roof, I was saving the eastwood stuff for the load area.

Here you can see a before and after of the overcab roof





and here are two videos that show the difference in sound.

http://www.flickr.com/photos/93190708@N05/11056824556/

http://www.flickr.com/photos/93190708@N05/11056865496/

Heres a photo of the rear roof section, underseat area and load area, covered in the eastwood thermocoustic









When I finished and started her up, I could tell the difference straightaway. I took decibel measurements on an app on my phone before and afterwards. The number seemed stable across a number of readings, so ignoring the actual numbers but treating them a relative, There was a small drop at all speeds afterwards. However, it's more of a different sound rather than quieter. Less tinny. I read somewhere that it converts the sound into a lower frequency. I don't know about that, but there feels less background noise in the cab.

I need to buy some more to finish the doors and the cab floor. I think that will make a big difference, as the road noise was still noticeable at speed in the front. Although the biggest difference was on poor road surface, where the sound is definitely lower.

In terms of the two materials, the cheap stuff, £20/metre, was OK, and you can see the results from the video. The Eastwood is way better quality though, and of the two, I would pay the extra money again. I might check out that tip about flashing tape, that comes in at around £10/metre from screwfix, I'm going to go and take a look. The eastwoods stuff was thick, easy to cut, no mess, sticks great. and in theory, has thermo properties, which the others don't claim to have. It also comes in bigger sheets than the flashing tape, but I actually cut it down to similar proportions most of the time as it made it easier to fit.

Left to do, I have doors, cab floor and behind the fridge. I can't get to the other panels without dismantling the interior, which I'm not going to do this year.

Keep you posted
Pete

[Drunk Aardvark]

Thanks for the useful thread. This on my list too so great to see how someone else has achieved it.