Generate a series of horizontal ribs on a multi-facial surface

Hello!

I wish someone could help me for a (surely) really stupid problem. I tell you in advance that i have already tried to search something similar in the existing discussions, but i havent find anything.

I would create, for a facade, a series of sunscreens/shadings following the entire surface, but I havent had any success in my tries...

Could someone tell me which is the way to make the following procedure?

1. create the shape desired

2. create the profiles on the shape by projection of a series of line

3. offset of the single line on the shape

4. generate of the surface between the two lines

5 extrude the surface created

Grasshopper is a fantastic software also because it's able to make rapidly actions that manually takes a lot of time, and I would escape to do this by hand...! So... someone can help me!?

Thanks a lot!