Wow you are so helpful I’m glad I found this page 😃 I live in Armidale Nsw I’m not 100% sure what a sub surface pipe is however I was…

134 square roof area not sure about ari was going to have 4 100mm Polly down pipes so 2 elbows and 3 ts or y junctions and probably 2 45…

I’m building a shed and the gutters are only 800mm higher than the street gutter level and about 47 meters from the down pipe to the road. My question is…