Fast, efficient and a good communicator throughout. The issue was ultimately with my roof and once up there to fix the valleys, his assessment was that further work was recommended to fit brand new membrane and re mortar the tiles to adequately solve the damp issue. As I couldn't get up there to see the work myself it was easy to be sceptical about the validity of this additional work being needed but he gave a clear explanation of the issue, shared pictures and showed me the deteriorated membrane and crumbling mortar, offering a reasonable price to complete all the works. Very happy with the experience and I'd recommend using them again.