First, TPO has been around for about 25 years, not ten. I inspected an American Legion Hall with a 60 mil TPO roof that was installed in 1991 and it's still perfectly fine. Flexible, good surface and intact flashings. It's the reason I was leaning toward the product. I admit I am apprehensive about doing heat welded seams. I've installed acres of torch down mod bit. I'm really familiar with the product but it does deteriorate if it stays wet and I'm afraid there will be a two inch mulch layer of maple samaras between the deck and the roof. With EPDM, I always see the transition over and up the cant pulling away and stretched like a drum skin. And, with an L shaped balcony there'll be a seam pulling in shear. Tom, I paid $900 for the 26 gauge, terne and a couple boxes of clips. I'll sell it to you for your porch roof. Or, I'll die and it'll still be taking up floor space in my tool room and my kids will toss it in the trash. Steven, I have a fiberglass skill set and I just watched YouTube videos from some guy in England. (fixmyroofUK) I think that's the ticket for me. Do you know where I can buy the pre-made flashings?