Chimney still leaking

[lena Cowan]

Had my chimney repaired 8 months ago but has started to leak again with the heavy rain in the last few weeks. Roofer repointed, releaded, new flaunching. Had another roofer look at it and he's said it's a bad job and needs silicate on brickwork too. It's porous stone. Original roofer says job he's done is fine and just needs silicate.
Would appreciate anyones views on who to believe

 

[Wayners]

We had similar problem and I also spent money trying to stop water getting in.
I ended up using foam around inside.
Theory was the driving wind blew rain water in.
I tried hose pipe on roof and could never get it to leak under lead flashing.
Get the wind and rain and sometimes it dripped in loft.

 

[ree]

OP,
1. Its hard to tell how correct the pointing is - were the beds & perps chased out 25mm or was the pointing skimmed over the old pointing?
2. The flaunching is shallow & maybe, looking at the edges, maybe that too was a skim over the original failing flaunching.
3. The pots are slightly skew-whiff, & so are the Colt "Birdguard" cowls.
4. The back gutter is wrong & needs doing again.

 

[^woody^]

Where is the water getting in? What is the damp staining pattern?

It's no good coating the masonry with a water repellent if the existing mortar is poor, as the coating won't work with poor masonry joints. Nor if the mortar joints are not the problem.

 

[^woody^]

This needs looking at. There's two routes for water straight away

Back gutters are a bit involved and should be soldered. Roofers are not typically experienced in doing this, it's a plumbers job.

 

[catlad]

Lead work is poor! also needs a lead-welded back gutter, not some pieces stuck together with lead seal.

 

[ree]

OP,
I'm now on a different screen & can see your pic more clearly.
Back gutters can be bought off the shelf - see: justlead.com (& similar sheet lead fabricators).
But first the bit of carpentry supporting the back gutter, & the felt underneath the back gutter will need correctly arranging.
A good practice flat back gutter board 150mm - 200mm is best needed.
The slates behind the back gutter will need lifting to correctly re-arrange the felt & install back gutter.
In short, you need a roofer who is also a lead worker to do what I've suggested.