Bay window leaking - lead flashing or wall?

[SummerHouse]

We have a leak. It seems to be from about a quarter of the way down the wall as opposed to from the top. We have a roofer coming to look - it's lead flashing. But just not sure it's a roof thing. Anyone have any experience?

It's the little bit of wall next to the blind.

It is really difficult to see where the damp bit is on the photo. Could you post another one and then one of the outside of that part of the house please?

Thanks @Geneticsbunny I will get some pics in daylight tomorrow.

Extra pictures.

Are the downpipes all working properly when it rains? Have you had them unblocked recently? Your pointing looks fine so if the downpipes and guttering are all working properly then I think it is a good idea to get the flashing looked at.

Thanks so much @Geneticsbunny

The downpipe has stuff growing out of it! I have someone booked to do all the guttering now. I have been out in the rain a few times now and it does drip from the gutters but it doesn't look like it could cause this much leakage...

It won’t take much more than a few drips to slowly saturate the wall and cause damp, I had a very similar problem on a wall in my house, it was a slightly dodgy join on a corner section of gutter. I solved it with a product called Geocil the works, a type of waterproofing sealant.

So perhaps get out on a ladder if that’s possible and see what’s going on either when it’s raining hard, or pour some water in yourself and have a look.

Am not saying it is definitely that, but it would be good to eliminate dripping gutters as it seems the most likely cause.

Looking more closely at your pics, the inside one looking high up at the window, there is slight water damage on the coving, looks like the damp runs all the way down from the top.
And then looking at the outside pics, flashing looks ok, it’s probably water dripping or leaking from the gutter around the underside of the soffit and running down the wall, it looks a bit damp there too.

Dripping gutter near bay windows can run in weird ways round the flashing and find tiny little holes in the window frame which normally wouldn't get enough water in to cause a problem. Definitely worth unblocking those first as it might just solve the issue

Thanks very much all. I feel really reassured that it may well be guttering for which we have someone coming this week. Then I will take off the wall paper (it's lining paper) and refresh it and see if that does the trick. Fingers crossed!

It will take ages for the wall to dry out, like months so don't assume it hasn't worked for at least a couple of months

We had very similar. A bricklayer investigated and it was due to a ' cavity wall tray' above the window being laid incorrectly so rain didn't drain out through weep holes (or something like that). Always worse with driving rain.
We needed it all removing and brickwork replacing. Cost about £1.5k.
Hope yours is more simple.