Hard to tell without seeing how the data flows but you do run it 4 times. Put a print string right after Then 4 → how many times does it fire? If more than once, you need to go further back and see why build floors fires more often than it should.
So I just tested printing it before I use the for loop, I get just 16. This also means that Build Floor is only being fired once since if it was being fired multiple times. The number of instances would be higher than 16 in the Then 2 pin.
I think I might just do what I’m trying to do outside the for loop and use the Then 2 pin