Do I need to worry about my chimney stacks?

[melikescheese]

I moved into my late Victorian (~1890s) two-up-two-down terraced house just over two years ago and have had very few problems (a bit of condensation damp upstairs fixed by improving loft insulation; turning up the heating; and running a dehumidifier now and again plus some easily fixed boiler issues).

One thing that I had on my survey was the lean on my two sets of chimney stacks (front and rear). Neither are in active use and the rear has had the stacks on the roof and the breast removed in the downstairs room. This hasn't caused me any bother and the rear still looks fine but my uninformed spidey sense is wondering whether I should be worried about the front one. I can see lots of brick dust up in the loft (see below) and it's coming down the chimney into the upstairs bedroom also (see below #2)

It doesn't look too bad from the exterior, but definitely has a lean and I'm not sure the remaining stacks and TV antenna are helping.

My two questions are:
1. Should I be starting to worry or this just a normal sign of aging?
2. If I wanted to fix it, what would need to be done [I've assumed removal of the part of chimney above the roof and how much would it cost (estimate)?

 

[blup]

The block work is not original, possibly its been added to address compartmentation issues where gaps in adjoining roof voids can spread fire. The brick dust might be as a result of drilling or removal of bricks in that area. If so historic and should be a concern. Did the survey mention anything? A wider angle pic would help

 

[blup]

* not be a concern

 

[noseall]

It doesn't look too bad from the exterior, but definitely has a lean

Most older stacks have a lean. It's to do with prevailing wind and how it cools one side of the stack and not the other. Yours look like they are in good nick.

 

[RandomGrinch]

. I can see lots of brick dust up in the loft (see below) and it's coming down the chimney into the upstairs bedroom also (see below #2)

The brick dust is from spalling.
It is common on old Victorian chimneys, where past conditions of dampness, a leaking roof and decades of continuous chimney use degrade the bricks.
Whether it is a problem depends on how bad the bricks are and how many are affected.
If there are only a few affected, something like SBR can be applied to limit further dust production.
In your case, the majority of the bricks look to be well in place.

Others may have differing opinions!

It's a little difficult to tell - have the bricks below the purlin moved out from the chimney, or were they built like that?

 

[melikescheese]

Bricks below the purlin were built like that as it is the same on the opposite side, which has less of an issue.

Brick dust is definitely more recent as I redid the insulation in the loft last year to deal with some condensation issues.

Sounds like it's just natural aging - thanks folks! I'll consider SBR to reduce the dust (though probably in the spring when it's a little nicer to work up there...)