This is what I did ;)
I made my design wall out of 1-1/2" insulation foam from Home Depot. Asked them to cut the sheets in half top to bottom, so I could store them stacked behind my door. Covered them with white flannel using super 77 spray glue. I just don't think the PVC is going to give you the regidity you will need
My sewing studio is upstairs so I prop my wall up at the end of my hallways so I can get a good look at my quilt as it grows during construction. This is very light weight and has served me well now for over a year