One day I am going to build it with the double-ring hubs as seen on this website www.ziptiedomes.com.
It is nice that the author of the above video provides the PDF file for this type of tunnel greenhouse which I also list here: geo-dome.co.uk/freestuff/cw18free.pdf
I have found a way to build the external cover with polycarbonate sheets and inner layer with PE films. Dividers will be built together with the inner film.