Steel structure workshop/building Certificate:ISO9001:2000 Steel grade:Q235/Q345 Safe and reliable Easy to install,firep Detail information & advantage 1) the main steel frame ---- welding H steel . 2) fast construction -----time saving , lalor saving ,easyly installatioin. 3) insulation panel ----EPS, XPS,Rock wool , PU sandwich 4) surface treatment ------anti-rust paint with 2 layers 5) good ...