Dormer/chimney water leak - help!

[mfsx9mb4]

We had a dormer loft conversion on a Victorian semi done back in 2018/19. Since then we have had issues with damp/wet patches on the chimney breast wall - see attached photo.

We have now had a roofer re-flaunch the chimney, secure the pots and undertake work on the ridge where the flat roof dormer meets the chimney breast. This has resolved many of the issues - 99% of the marks in the photo are now no longer becoming wet during heavy rain (obviously they need sealing/redecorating). In short, we thought the issue had been resolved!

Unfortunately recent rain has seen a very small wet patch reappear - circled in red on one of the photos. It is very small, about 1-2cm in diameter. I also attach a photo of the external patch job/works. This patch falls directly underneath where the ridge falls into the pitched/slate roof, where felt has been torched on (over existing lead/step flashing an soakers).

I would welcome any advice as to what action we should now take to resolve this issue as we just can't seem to fully solve it (although most of issue has now been resolved). Thoughts gratefully welcome!!

 

[danfre]

Felt dressed up the wall isn't the best , should really be done in lead chased into the brickwork.
Looks like you have flashband along the edge, would only consider that as a temporary measure.
Think you may be in need of a competent roofer

 

[ree]

OP,
As above and:
The general appearance of the roof cover is poor - whoever did the work made some bad, & inexperienced choices.
All the stack flashing, new & old, needs replacing with best practice leadwork.
The pointing needs re-doing with lime mortar set in 25mm depth chases.
Cement mortar re-pointing has been previously smeared on top of the original lime mortar, & it's failing.

Pics with a wider context, and a pic showing the flaunching might help?
Remove the old TV aerial if its redundant.
Have the chimney flues been swept and vented?
Whats the purpose of the scaffold?