roof

I have a gambrel(some call it a hip roof) "barn" with a shingle roof, a lean to with a standing rib metal roof that is attached. Never had any leaks until about a year ago I first had 5 inch D spoutings put on with similar downspouts running into underground pvc to carry the water away...

We live in a semi wooded lot and there are some pretty good dark stained areas on one part of my roof. I've tried various products by several manufactures (30 Seconds Outdoor Cleaner, Scott's Outdoor Cleaner, that have in the past, worked well. on lighter stains. Even at full, non diluted...

I want to replace my roof. I noticed some roof contractors make valley with metal (sorry, i dont know the terms, i guess it is valley flashing but might be wrong) and some just overlap shingles. Does it make any difference and which one is the way to go in your opinion?

Actually I can stand under it and stay mostly dry, even in a downpour. An old farmer pointed that out to me years ago as we were talking about rolled roofing. Installing it vertically allows the water to run down the edges. He said that a lot of old barns were built without shingling and didn't...

From my viewpoint slate looks the best. But I would suggest steel with one of the more appealing patterns.