So I have been looking at this for a while now and Dynamat is rated very good, and silent coat every bit as good but half the cost. makes sence to go for silent coat and get better coverage.
I recently spoke to a Guy at Custom Vanz and after reading thier web site and simply said
"Don’t be fooled by companies offering D-Matting, Dynamat or similar as a Sound Deadening Treatment.Whilst these materials will eliminate a small amount off road noise, these materials are anti vibration products used in Audio Installations to stop powerful speakers vibrating panels, door cards and dash trims, ect.They are not dedicated sound deadening products"
So
@Buggirl no it wont provide insulation or sound deadening, but it will add weight to the pannels that wiill vibrate due to other vibrations in the van, whether that is due to a sound system or whatever they will deaden vibrations that can be heard as sound. so in all will help.
If you look at my earlier 3 stage sound, insulation and carpet thoughts, it will give you an idea of what I plan. Others will do it differently by filling the voids with a wadding type insulation and this is going to be down to choice for me. and depending on cost i may well do both the silent coat insulator and wadding ... Most are availible as peel and stick. as
@superflyguy states maybe peel a wee bit off at a time before attempting to stick down a full sheet. Will be easier to peel off if ya F-up