As always, there are many ways to cover a flat rook. I have been felt roofing since June 1973 and have heard a lot of people talking (IMO) some rubbish with regards to felt constructed roofing. If the applier is doing the job right, there is no reason for not going down the either: Hot Poured method or Torch-On methods. Felt Roofing materials have advanced greatly over the years. Like most things in this world.....preperation, care and attention to detail are paramount when doing the job.