Cement Render or Vermiculite

[Snapper]

G'Day Pizza Lovers,

My name is Breen, new to the Forno Bravo world and I am half way through building an oven.
I have seen some beautiful projects on this forum and thank all who have unknowingly helped me to build my own.

I am a chef from Australia who at one stage worked a traditional wood fire oven imported from Tuscany. As you all know too well, once you have fired an oven for the first time you're hooked for life!

Please forgive me if this next question has been asked time & time again.

I need some clarification on the final stage of the build. I have been told from an oven manufacturer in Australia that after the insulation blanket then all I need to do is cement render over the top. Every one on this forum has mixed a Vermiculite render. What is the better advice and what mix ratio? What will the end result difference be?

Snap.