Dear Dr.SupaNova,
You may need a degree in civil engineering to become a designer. Being able to know what to use, and when to use it, in terms of architecture, helps as well.
I would have no doubt someone with a degree in civil engineering would be quite likely to get a job in areas such as going over designs, or even, get you a job in manufacturing!
Hope this helps!
Yours Truly,
TKCMDR