Perpendicular profile in sweep?

Im after something seemingly simple but very complicated to figure out:

I have a series of columns (diagrid) running at angles up the facade. At the moment I have them mapped from unfolded elevations which all works great, I have them move left 200, move right 200 on the target planes, loft and extrude to make nice box sections.

What i actually need is profiled sections, ideally sweeped off a series of profiles which i can adapt live and they will update in my 3d diagrid model.  Sweep is fine but only if i place the profile at the bottom of the rail curve, and only if it is perpendicular.  

Can I skip all of this and have a way to keep a set of profile curves in 2d the file and reference them to sweep along the 3d curves?

Hope this makes sense... questions welcome!