I got a set of faces, how can i build a Shell ?

i'm loading a Solid on its IGES format, so i'm able to construct a set of faces "separated" (so a face don't know that it's connected to another one via an edge)..how can i build a solid from that ? what i saw is that a Shell is constructed only from Surfaces that are parametrized !!

Can u seriously answer , 'cause this is my third question on this forum without any response.

thanks