David Sevostyanov don't assume nails are meant to hold down shingles temporarily the tar sealant which is activated by heat from the sun is the most important part to a shingle roof system
Mohawk Guy....I am a mature Woman and i have skylights on my roof.....one of them has been a pain in the......but i must say it is located on a flat roof......many (four times different people have come to repair it promising it will not leak again) and now i feel i have acquired some knowledge......and i feel the way your are doing it is not going to be very good.....you need to research some more to acquire better knowledge......Thanks for the effort......
No, two or even three inches is good. It fills ups with leaves and debris, you need some room up there for it to wash out. If it’s just a half inch or so it get packed in there and creates a damn, it can then spill over the sides of the flashing. You want to see a nice gap on the flashing all around and let the water flow away and out the bottom!