Plumber is on site and about to run gas pipe from plant room to kitchen island and concludes cannot run gas pipe under a suspended floor. Our floor is beam and block.  I have run yellow 110mm yellow gas ducting from plant room to kitchen island location. Plumber says can't run any kind of pipe under the suspended floor (including Tracpipe) even though the pipe will be run in the 100mm yellow ducting.    Anyone encountered this and found a solution? Only option I can see would be to cha