Question on intersecting valleys

I’m redoing our roof down to the furring strips and am running into some not-great roof design that is causing some issues on the valley design. Our roof, outside of the dormers, has generally two slopes - the more shallow (I didn’t measure but I believe it’s 3:12) on the porch. The convergence I’m hitting is where the main roof hip ,which has a decorative dormer on it, runs in to the porch roof. As it’s an ugly design with the porch roof cutting off the roof hip on one side, I’m going to extend the hip to terminate beyond the porch (red line on pic showing it’s new path) - I’m also doing this as this was a drainage issue to begin with which caused a lot of leaks. The problem now is I have a crooked valley. It was already converging at the dormer but now will have three angles. How is the best way to flash this valley. I was going to use W-flashing but am not sure how to connect three of these pieces due to the W ridge. The pic shown is of a neighbors house but it has the exact same roof.
roof valley

Hire an experienced roofer.
Dont change the design.
Hire someone with decades of experience.

The original design was bad and caused leaks so it’s being amended (plus it looks half-assed because it was done half-assed). “Experienced roofers” around here managed to screw it up constantly since then and now I’m tearing off 9 roofs, replacing 1/3 of the furring strips, decking the entire roof (it had none - just roof on roof on roof on roof, replacing most of the fascia, partially replaced the porch header, and on and on (there is no training required in Oklahoma for roofers and there are no roof inspectors in Tulsa not that any roof inspections are required here and it shows looking at the jobs done by roofers in our neighborhood who just kick out crappy jobs and race around town in their bro-trucks). I’m doing it all myself and it’s turning out great - all the decking has custom cuts to hit the rafters (which are walking all over the place thanks to sketchy framing), all hot-dipped galvanized 8D nails on the decking - hot-dipped nails for the shingles too, everything hand-nailed - no guns, ice and water shield below synthetic underlayment and on and on. I’ve gotten a lot of great info from this forum and a few others but have found nothing on intersecting open valleys. Before it was a closed valley that went in to an open valley that dead-ended on to two intersecting roof slopes which caused water to get under the shingles and rot the fascia, soffits, interior walls, and porch. I’m trying to run an open valley all the way down but there is no way to have a straight run. If anyone has some actual advice on how to do this it would be much appreciated.

It was a drainage issue and looked shoddy because there were unqualified roofers installing it, as you have pointed out. If you extend the hip you will have to completely reframe the valley, otherwise it will have no exit point.
Roof lover is right, this is a simple detail for a quality roofer to make look good and not leak the way it is currently framed.
On another note your neighbors valleys have the cut facing the wrong way.

My mistake I saw the cut valley wrong.

One important, and easy, fix for this current design is to not extend the hip cap down so far on the valley side. It is definitely catching water.

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Yea - and two other houses in the neighborhood with the same roof have the hip cap the same way and all show rot issues in the convergence. However they all also have closed valleys in the area while ours had closed, open, and then clusterfuck. Currently it’s exit point (if you’d call it that - it doesn’t really have one - it just runs into the other roof) is throwing water onto the porch roof which is a more shallow slope. It’s just a bad roof design that looks as bad as it performs. For all the ranch roofs I’ve looked at I’ve never seen one quite like this.

Here’s another similar roof on the street - you can see previous roofers tried to elevate the porch area a touch over the garage area roof. It’s okay from straight ahead -
roof valley 2
But from the side you can see the water from the gable is just being forced into colliding with the water running down the porch area which is saturating the lower slope porch roof and also spilling over the hip onto the garage area roof. You can tell the area is already rotten.
roof valley 3

It’s a lot of fast runoff hitting a shallow slope and causing issues. I’m at the point now since I’m up to this area to rip all the old roof off in the area down to the framing and see what I can do to allow a valley that will empty at the roof edge.

Run ice and water up the valley, all three angles, with 18" on each side of the valley, obviously starting from the bottom and working up. Overlap material at least 6 " inches at each pitch change. When applying the shingles (-which ever way you decide to do your valley) do not nail within 6" of the center of the valley (@ a minimum) you won’t have any problems. About the same thing as a 5 sided bay roof where a valley and a hip terminate at the same point, tho7gh yours terminate above the eave so run some ice dam out to the right at least a few feet past that termination pt. And then overlap that with the ice dam thats running up your valley

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Tileman and Rooflover are correct. This is an easy, everyday deal for a roofer. We see these hip to valleys all the time. A good roofer can make this water tight with no problem. The bottom 2 pieces of ridge would only get Roof lovers black bucket of crap under them,(Florida demands it) and nail high and to one side. You are making too much out of this, but hey, I’m just a smartphone keyboardist, sitting in my truck having lunch. Don’t pull decking off.

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There is no decking - this house still has the original 1955 shake roof on it covered with up to 9 asphalt shingle roofs on top of it. I’m stripping it all down to the furring strips, fixing all the rot, adding decking and going out from there. I’m sure this is an easy everyday deal for a good roofer but none of them around here can seem to do it (or at least haven’t on this or any similar roof in the neighborhood). There are no roof inspectors, no roof inspections, and no roof licensing in this area (outside of roofers needing insurance for their workers). I’m doing it all myself as 1) I have no faith in any of the roofers around here 2) the quotes I got were for incomplete jobs at sky-high prices (gotta pay for those bro-trucks I suppose) & 3) I’m having a great time doing it. I think the roofers on this forum are great - you all are experienced and conscientious which is lacking in this area and I really do appreciate the guidance. I’m ripping the roof in this area off today and then decking it which should give me a better view of the various colliding angles so I can rebuild the valley properly with the guidance I’ve gotten on here.

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