Roof mostly covered

The last piece of tile that needs cutting and folding is now done. It's yet another tricky piece requiring underside flashing because of the inside corner fold. I'll probably paint the galvanized valley gutter to match.

Tiles at skylight

At any roof penetration, shaping the tiles is definitely a challenge. This particular skylight is not too important because it's exterior space below, but the proper procedures in controlling rainwater runoff had to be followed. It's good practice for me because I plan to install a similar skylight in the kitchen.
The toughest pieces to cut and fold are the ones at upslope and downslope. They require folding across the scallops and around two corners. From lessons learned the other day, I created a wooden jig shaped to mimic the tile contours to use as anvil. Hammering the tile edges just enough resulted in a curved fold that maintains the tile width and not flare out or crease together. It's almost an art. Proper-height battens underneath support it from collapsing in.

This is not for the short attention span. I had to simultaneously consider the low pitch angle by shimming the battens for potential puddling of rainwater on each scallop, figure a way to install a flashing skirt that would fit snug all around, and how to attach the skylight itself since the entire height of the 2x6 curb is taken up. I think I have a solution.

Gutter right turn

The lower part of the valley gutter is now complete. It came together well. Actually, I wish I had made the metal trough narrower because the folded tiles had to wrap tight over it, exposing a gap that can be seen from below. I guess it's good for visual checking of debris without using a ladder.

This has become quite a different roof compared to the torch-down bitumen that was planned and started. See photo of the roofer's solution.

Lip flashing

Another really tough situation is where the front lip of the Decra-tiles fold down into the valley flashing ("valley gutter?"). The scallops make straight-line folding near impossible because once it's flattened, it flares out. It's basically corrugated sheet metal. The only way to create a straight fold is to splice it up each scallop mini-ridge, exposing gaps at the folded corner. I have several pieces like that. One of them even tapers to a point at the fold!

So to seal against penetration at the gaps I've installed bent flashing under the lip. It gets hidden (almost), so this photo is proof that I've installed it.

I'll probably go back and dap roofing cement at the gaps for good measure.

Half lap roof tiles

Here's a seam that's labor intensive to construct when extending a Decra-tile roof. It's where the last row of new tiles meet the "first" row of existing tiles (the original first row at the eaves have been cut off). Roofs are always installed from the bottom up, establishing the position of all the pieces above it, so this less-than-full lap was unavoidable.
I think my solution created the least amount of work. I took advantage of the change in roof pitch. On the last new row I top-nailed a 1x2 batten through the tile to another batten positioned below it. The combined assembly must factor in the thickness of the tile scallops. But because of the pitch change, there was some room for error. It also required that the rear flanges of that last row be cut off. This is all easier said than done!