I forgot to say Guys that- firestone will even cut it to shape, so that it is ready to be fitted as it is! Just saying as it may help you to have less work to do in the future on all the other roofs you have to put right. Hope this helps. I only know this as I phoned and spoke with them about mine.
Sorry for the mistake. It's not a covering I would use. The membrane itself is a long lasting cost effective roof covering. If done properly. The problem is most builders do it themselves. Thinking a 3 hr corse makes them an expert. Same thing applies to grp