Convert a line to an area with a thickness

Hi, I am wondering if there is anyway that I could convet a line to a surface. Please see below for a better undrestanding. I have a pretty complicated centerline of a steel profile and I like to convert it to an area with a thickness. I have attached polyline GH file as well.
Query.gh (2.2 KB)

Hello- in plain Rhino, Offset with Cap=Flat. If needed Hatch or PlanarSrf the result. Does that do it or do you need a GH way?

Something like this, I guess - you need to make your own caps to the offset.

-Pascal

Many thanks. GH is a great help for me.

That is really great. THanks

More like this with your example as a starting point:

-Pascal