Maybe I'm misunderstanding, since I'm confused by that arithmetic - 179-178 = 1, not 10, and nor would your figures make any sense as centimetres.
Kind Regards, John
Sorry, looks like I had a right blonde moment there.
178x102x19 UB S355 is listed in the Structural report for the beam (I'm assuming the 178 is the depth?)
Actual depth of the joist is 195mm
Also just noticed this sticky stuff on one of the cables, should I be concerned?
Cheers