Hi Pilou,

> You don't like my method? :)

You mean for building the side walls? Your method would work, but extruding a bunch of faces like that is going to make a lot of individual solids, so then you'll probably want to do some extra steps like selecting all of those little solids and doing a boolean union to combine them together. That would work but it just more steps than selecting 2 curves and using Loft...

- Michael