How to install bifold/multifold doors?

Hi Folks,
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I am doing an extension and as part of that I need to install 2 multifold/bifold (why are they still called bifolds if there are more than 2 leaves?) doors into a new wall and 1 into an existing wall. My question relates to how to position the door where the door frame is 140mm and the wall is only 105mm (including plaster and cladding etc. – 70mm framing was used). The existing wall width is huge because of battens etc. however where should all the extra door frame go for the new 70mm framed wall?

I have attached a quick picture (make sure it is full size in your browser so you can read dimensions etc.) showing the detail and have included how I had envisioned it would be installed which is having the frame flush with plaster on the inside wall (architrave then attaches nicely) and all the extra on the outside however this will leave 35mm of frame protruding past the chamfer boards so is this correct or how should it be fitted?<O</O
<O


Thanks in advance.<O</O