For some fell running races it is mandatory to carry full waterproofs including non-detatchable-without-scissors hood. James already has the waterproof trousers, of course. He also has a mountain climbing Goretex and a cycling Goretex. The latter is 500g, and would do, but it is a bit baggy and doesn't fit in James' tiny fell running rucksack. He asked for smaller and lighter. For running, one wants something fairly slimline, so I started with the pattern for the cycling windproof. If using this pattern again for cycling I would add more ease across the back, as the stitching tends to come undone at the back arm seams, but for running it should be fine. I had some fabric - a nearby outdoor store that made much of its own gear closed down recently and sold off a few metres of fabric amazingly cheaply. The fabric is heavier than Pertex and clearly waterproof, but I'm not sure how breathable it is - possibly not very. However, with pit zips and a zip down the front of the jacket, there are ventilation options.
The only really tricky bit was devising the hood. James decided that the snug collar of the Pertex windproof was desirable when the hood was not in use, so it seemed that a hood that tucked into the collar would work. James' cycling jacket has that kind of hood, so I copied that hood shape. What I did wrong was fail to allow for the space occupied by the rolled up hood inside the collar, so it is a bit tight. However, this is mitigated somewhat by the extension tab at the back collar (also copied from the cycling jacket) which means that the hood does not have to be completely inserted into the hood.
And here's the hood. It now has a single snap in the middle of the centre front, because for running James wants it to fasten under his chin, not over his mouth.
Of course, I minimised seams, but I also found a nice roll of seam tape on EBay and taped the raglan seams as well as the pocket area. Doesn't seem much point taping the underarms, given the pit zips. But perhaps I will have to. The rules say, 'The FRA regards "waterproof" to be a garment marketed as "waterproof" (i.e. not just “windproof”) with taped seams.' Now that's tricky - this jacket isn't being marketed at all! The vulnerable area for water ingress could be the front zip as there is no storm flap. Looking at the running jacket market it is clear that the really lightweight ones are not really very waterproof and just for emergencies (or even just for carrying!), as they are made of very thin fabric. My version is actually quite a sturdy mid-weight laminated fabric. Final weight, 302g before the last snap was added, so probably 305g, which is very competitive given that published weights are for M-size jackets and this one is of course an L (well ... XXL length and M width ~= L).