I need to design for a cinema and i would like to ask some opinions. I plan to use the space frame as the roof sturucture of that cinema. Which component is suitable for this building? I would like to find the material which is strong but light. and what are the affects of the deisign on cost, programme and developement of the cinema and its major structural components (foundation, number of columns, thickness of floor slabs)? i will be very glad for those who can give me the opinions.. thanks so much~ :)

Planned size?
Budget?
Availability and proximity of materials suppliers?
Etc etc...

For steel construction, your beams will generally need to be 1 foot tall for each 10 feet of span. The columns generally match the beams.