While the cargo area insulation is to be mainly thermal, the noise seems to me to be the most important thing regarding the driver cabin, especially with a noisy vehicle and a noisy diesel engine sitting between the driver and the passenger.
As with thermal insulation, there are many opinions floating over the internet in regard of sound insulation. So far, from what I read, in my case, the way to do it will be mostly by damping by absorption: reducing resonance in the room. To that effect, I picked:
- a layer of (2.5mm width) butyl panel (read here, here and here) ;
- a layer of (6mm width) rubber foam.
I selected these from what bitmat.pl sells because they are readily available and match the price I was prepared to pay for this. But you can get thinner butyl panel which are either less effective or much more expensive for instance. Same goes for rubber foam, you can take 50 mm instead of 6mm, though that may reduce considerably the cabin space 🙂
Most comments seems to agree that butyl panel have less effect on the most rigids part of the vehicle (floor, etc) and that, in general, it is not necessary to cover more than 25 to 50 % of a panel for best effect, the gain after that being minimal. You can obviously cover everything but it will be more costly and heavy.
There is really nothing complicated to put these butyl panels. They glue by themselves, there is no layer of glue in between. They can easily be cut by metal scissors and often sellers will provide you with a dedicated roller, to be used to properly press the butyl panels against the vehicle panels.
Nonetheless, it is convenient not to cover bolts/screws otherwise necessary to put back stuff in the cabin and important to preserve the small corner holes on the floor (water exit, etc).
To do the whole cabin, I bought 1200 x 50cm of 2.5mm butyl panels (first 400x50cm, then twice the amount) but I have extra ; 1000×50 would have been enough.
I also bought 550×100 cm of 6mm rubber foam, which I used fully.
zestaw wygłuszenia wyciszenia pary drzwi AB-25 K6s = set of 400×50 AB-25 butyl panel, 200×100 K6s adhesive rubber foam and dedicated roller (249 zł)
K6s mata wygłuszająca pianka akustyczna 350×100 cm = 350×100 K6s adhesive rubber foam (135 zł)
mata wygłuszająca butylowa bitumiczna butyl 2,5mm 400×50 cm = 400×50 AB-25 butyl panel (2x 170 zł = 340 zł)
kosztuje = 249 + 135 + 340 = 724 zł = 157 €. Żukventure cost so far = 3936 + 157 = 4093 €