... steel H section. steel materials: Q345 & Q235;2. The columns are connected with the foundation by ... Section;6. Surface Treatment: Rust-proof Painting with 2-4 Layers; 7. Span: The max span ... X eave height, roof slope2.typesingle span,double-span ,Multi-span,single floor,two story ... . Dimension: Length, width, height, eave height, roof pitch, etc. 2. Doors and windows: Dimension, quantity, position to put ...