I inspected a kiddie jail in Naples Fl made out of this stuff (Ytong). They used a big router to cut the channels and mortared over them. No Romex, it was EMT.
It turned out to be a problem because in spite of the skim coat of fiber reinforced concrete, the little weasels figured out they could tunnel through it with a spoon. The builder also had a huge problem proving he had enough fire resistance (fire marshal signoff) but the manufacturer finally came up with the testing data.
I have a core I picked up on the job and this stuff floats.
