Does anyone have an idea of the overall area (sq. metres?) required to do an SW20 ?
including the boot.

I used nearly 2 full boxes to do the interior in its entirety if that is of any help. However, I have a hardtop.

Why would you want to do the boot out of curiosity? its so far disconnected from the cabin

Hi Eric,  sorry if Dynamat comes in only 1 box size , but I am still not sure how many sq meters I need. 
 
 As to why do the boot ?  resonances.  I don't care about engine noise going through to the boot, but resonances travel through the chassis/body.
I have no idea if there actually are resonances from the boot.. but that is the principle. 
 cheers
 

Here is the box I used. it contains 36 square feet

https://www.amazon.com/Dy...r-Xtreme/dp/B00020CB2S

I think that the boot is unnecessary in my opinion. If you put the deadening in the C pillars and on the firewall, it should remove any resonance from getting into the cabin from the engine bay

Cheers,

Thanks Eric,
and good point. 
 

Hi, I though I might want to share my experience.
I sealed off the big cavity space above the rear wheel that link the boot into the cabin with expandable foam ( construction/marine foam spray can ). You will need to remove the plastic panel below the quarter window. It seal out noise and smoke from the engine bay too. I also filled the chassis structure with expandable foam too. Together with those recommended panel deadening with Dynamat especially the back firewall, get the thickest on the panel. Its worth all the effort doing it.