SO. Sunfold came back last week with the engineer and spent over an hour lifting out the windows (vents) from their frames, cleaning out quite a bit of gunge and resealing with what looked like Polyfilla. Then it didn't rain for more than 15 minutes for an entire week. I waited and waited. We had a bit of snow apparently (didn't see it, must've melted by the time I got up). I've never wanted it to rain so much before. Finally, it rained. Last night it rained solidly for hours. And guess what? IT STILL LEAKS.
The good news is, it definitely doesn't leak as much. As far as I can tell the six leaks are now down to one though this might be a case of speaking too soon. The vents tend to fill up with water and drip hours after the rain's stopped, so it's possible they're still filling up.
The one leak is a nice bold drip which falls intermittently. The bucket has a very small pool of liquid at the bottom which is a nice improvement on the three inches of water it was accumulating in 24 hours.
The next step in our mission to not have leaks is to replace the windows/vents. And if that doesn't work we need to adjust the pitch of the roof to force the water to run off better. I'm not convinced by the pitch argument as surely the roof should be water tight? If water can't run off, shouldn't it puddle instead of coming inside? Or maybe that's just me being old fashioned.
To add to the seasonal change, the leaves have dropped so the light in the extension is a watery winter harshness. Instead of looking at lushness we can see the neighbour's house again. (Pictured at top)