How to fix small cracks in flaunching?

[rhythmstick33]

There are a couple of very narrow cracks in my chimney flaunching.

The first one is about 1mm wide at ots widest:

The other one is a bit narrower:

I'm worried about the cracks getting bigger and ultimately letting water in.

A local builder has suggested using Leadmate to fill the cracks.

But I also heard that you can use some bonding compound (like this one: https://www.wickes.co.uk/KA-Bond-SBR-Co-Polymer-Bonding-Compound---1L/p/139061 ) that I can dilute and hopefully fill the cracks with.

Which option would be best? Or would you recommend something else?

Any suggestions much appreciated, thank you.

 

[catlad]

Bit late for that, You can paint it with acropol.

 

[rhythmstick33]

Brilliant, thank you.

 

[^woody^]

Cement grout

 

[rhythmstick33]

Cement grout

Cheers, but I think I'm going to go with the Acrypol as it seems like it might give an extra layer of protection should any more cracks form in the flaunching in the future.

 

[ree]

OP,
You asked previously about this chimney stack. Others & myself took the trouble to give you specific advice - you dont appear to have followed any of the advice you asked for & were given.
FWIW: the above flaunching appears to be just a skim of flaunching over a previous attempted skim of "flaunching".
If I am right then the cracks are irrelevant, because the "flaunching " will fail.

 

[rhythmstick33]

OP,
You asked previously about this chimney stack. Others & myself took the trouble to give you specific advice - you dont appear to have followed any of the advice you asked for & were given.
FWIW: the above flaunching appears to be just a skim of flaunching over a previous attempted skim of "flaunching".
If I am right then the cracks are irrelevant, because the "flaunching " will fail.

Hello ree, Some of the advice I've received has been conflicting, so I've taken whatever seems to be the best advice.

The issue may be that it's someone else doing the work, a roofer.

On his first visit, he blocked off a disused flue with a slab and did what appeared to be an untidy/incomplete job of redoing the flaunching.

So he came back having agreed to remove all the new and old flaunching, remove his slab cap with a proper terracotta mushroom vent and then redo the flaunching properly.

So, having read your message, it now seems he may not have redone the flaunching properly (again)... Can you let me know why it seems he's only done a skim of flaunching? Do you suspect this from the cracks or is there some other clue?

Incidentally, I haven't yet raised the issue of these two cracks with the roofer as I wasn't sure if they were the result of bad work from him or whether I may have caused them as I went up there after he went and replaced some loose render.

Could you shed more light on why you think he's only done a skim of flaunching over the old?