Ofsset of a complicate surface

when I have a surface, in this case the shape of a chair, and I want to make a loft so that this chair has a thickness. He does not let me do it. and when i got to do it, i put thickness and these separates the whole figure.
francisca campos.gh (32.3 KB)

Have a try pufferfish plugin.



francisca campos_re.gh (33.1 KB)