Cedar creeper trellis design

I am thinking of constructing a balcony screen comprising a steel frame with horizontal (untreated) cedar slats. If I want this to double-up as a creeper trellis, what design considerations should I take into account, e.g. spacing of slats, etc? Also, will cedar influence, or be affected by, the type of plant chosen? I have heard stories about some plants "strangling" and deteriorating timber....