Knocking through kitchen into dining room and need to fit a 3m rsj(this is including overhang) Im hoping a 203mm rsj will suffice for this and will get a structural engineer to properly calculate this, question is if the joists are running the opposite way to the rsj can they be notched slightly to lift the steel higher into ceiling to gain height as want to run a row of tall kitchen units under the lintel and gaining even 20mm would greatly help.