Leak through chimney

[MacLaverty]

Had the roof re-done last Jan including chimney flashing. When it is stormy and there is wind driven rain against the chimney, water is finding it's way behind the flashing and down into the loft space. I have had the roofers back after the last storm earlier in the year and they put sealant on the lead step flashing where it sits against the brick to stop driving rain getting behind the stepped flashing and done behind the speakers. However, from last night's storm water is still finding it's way into the loft as you can see in the pictures. Only a minor leak but one I am still keen to get sorted. Could it be that the lead soakers have been cut too short allowing water to get under the flashing or could it be other issues with the chimney?

 

[Wayners]

I had similar. Had new lead and still leaked.
I could not recreate the problem when I got the hosepipe out.
I fixed it eventually with foam inside loft. I think it's stopped the wind blowing the rain under tiles.

 

[MacLaverty]

Where did you put the foam?

 

[Wayners]

I sprayed foam around chimney

 

[MacLaverty]

So the foam went underneath the lead flashing above? I think this would be my very last resort as roof is still under guarantee.

 

[ree]

OP,
Dont use foam either inside the loft or outside around the stack.
Each soaker should have 100mm of cover & 60mm of upstand.
The 20mm formed turn of the step-flashing should go into a 25mm chase.
The step-flashing cut should be angled back - not square cut.
After pointing in the chase then no more sealing is necessary for any of the flashing.

Why not post more pics showing all four sides of the stack?
FWIW: the slate course below the apron is in disarray over on the RH side of the pic.