On 26/02/2021 21:03, AnthonyL wrote:
What is happening to my chimney stack bricks and why?

https://flic.kr/s/aHsmUwRSEW

It is a non-working chimney though I don't know if that has always
been the case.

How do I fix it?


Porous bricks that have got wet and the the water has frozen spalling
off the front of the bricks. Some attempt has been made in the past to
stop this by painting the surface.

https://www.youtube.com/watch?v=OW6GzBPYk5I

It's not obvious how that tall mast is secured but perhaps its not doing
your chimney any favours as you also seem to have cracks running through
the centre of bricks.

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