I'm knocking out my rear wall for my extension I've been told to use 2 x 203x133UB30s steels with 152x98UB16 C section welded to one and bolted to the other this bit fine what they want and im not shore of is this bit
2 203 x133UB 30 with 152x89 DIAPHTAMS AT 900MM CENTRES
THE BEAMS ARE...