The job was to make the loft space into a useable space with storage & I was informed the company was loft conversion specialists. I had to stop the work as it was evident they were not able to do this work & were unaware of regulations. I am paying someone else a large amount of money to undo the substandard work & complete the job. I was persuaded my roof needed to be redone as joists & tiles were old & a large sum was spent on this work which was done with little care & much mess & dirt.