Bung:Aredwood: Please don't get the metal tiles. I hate them with a passion as a plumber. Their shape makes it far more difficult to reliably run pipes, flues ect through the roof.
Wouldn't tiles make it easier to flash as with corro don't you have to go up to the ridge flashing now?
Try running a large flue through a metal tile roof. Such as a woodburner flue or the flue from an open fronted gas fire. You are having to chop into multiple tiles, Their shape means that a decktite will never work reliably. The proper lead tile flashings cost far more than decktites and lead can't be used on colorsteel roofs.
On roofs that have enough slope to stop water damming a decktite by itself works perfectly fine. Friends of mine have a house with a metal tile roof that has previously leaked around the woodburner flue. I managed to fix it with some silicone (was leaking badly in middle of winter and needed to be fixed quickly, 2 other people had already tries and failed). Told them that if it leaks again I will need to install a pan flashing on it.
