In the past a "plumber" has run a pair of 15mm copper pipe from one side of the room to the other in the ceiling and notched every single joist on the underside to a depth of 1.5 inches. The notches are about 8 inches from the ends of the joist where they rest on an RSJ. The joists are 8x2'' with a span of 4m. The building regs state that notches on the underside of joists are a big no no. Realistically is this a major problem that should be remedied? I suspect this work was done about 5-6 years ago by the previous owner. The floor doesn't appear bouncy or springy from above.
Thanks
Thanks