Below are some renders of an unfinished structure I've made to protect a stack of wood next to an existing shed.
It's made of a very simple frame with a pin-and-hole fastening setup at the ends that attaches to the existing shed's support structure. The cube is just a representation of the shed, but the two dangling pieces (just touching the shed) are actual cutaways of the support structure of the shed that the frame is being fastened to.
I intend on covering the frame in sail fabric, but then I'm not sure how to transition the asphalt roof of the shed to sail fabric so that the rain going down the slope of the shed's roof doesn't fall off before it gets to the canvas roof. Looking for ideas.
Best Answer
The following is similar to a membrain that I did on my current home transition it has been dry for 3 winters so far. Run the sail material to the roofing with several inches to spare, use some 6" rolled metal flashing so this is 1 price. Put a layer of blackjack on 1 side of the flashing along the edge that will be the high side or not in contact with the sail 1 inch wide add a 1" stripe down the center. Place the flashing on the edge of the sail material so the material is only 3" or to the center of the flashing sealed by the blackjack. using roofing nails pin 1 end down in the center of the flashing into the sail. go to the other end and pull the sail material tight and tack just the sail down. Now go back and start tacking the leading edge of the flashing down every 6-10 inches. And the center about every 24". Once nailed down cover all the nail heads with blackjack. And make sure the blackjack pushed out and there are no voids if there is a void fill it. I used blackjack because I had several gallons but there are many different brands that will work. If totally flat there will be a small area where water tends to pool about the thickness of the material at worst case the rest flows to the side. If your roof has a pitch less water will pool. This is on a garage to barn transition so it is not a living space.