Chimney stack removal

[paul161201]

I am considering removing a chimney stack just below roof level
The chimney stack has already been taken down to four course of brick above roof and capped off with flagstones. I have taken a few chimney stacks down before but never one which is at the gable end.
if i remove this chimney whats the best way of forming a new apex i was thinking to disk cut the new apex into the existing brickwork.
Any pitfalls to watch out for?

 

[vinn]

There are probably two basic ways of doing this but its really a job where site calls are the most important, and any proper explanation would need sketches and photos.

You could drop the brick courses below the verge line or any barge board line.
Create a shoulder with say a conc flag(s) to shallow falls.
And then make good/replace any remaining inner chimney breast face wall with clean brick.
Then make good to the roof and verge.
Insert an air brick.

Another method would be to drop the brickwork as above, and then re-build to an apex using cut bricks.
The apex must stop below the barge board or verge line.
Make good to the roof and verge.
Insert an air brick.

There are too many variables to safely advise you eg. how the ridge and any purlins are supported, and its only after dropping the chimney breast below the verge that the particular building detail will be exposed.
Cutting with a disc might expose sooty brickwork, and how deep is the cheek depth? Is there a liner?

 

[paul161201]

Below is a link to images of the stack and damage it coursing, is this likely to be coursing damp issues in my neighbours house?
my neighbour has said his said is fine even from the one of the photos you can see a plant growing out of their wall.
http://s805.photobucket.com/user/paul161/media/c 2.jpg.html
http://s805.photobucket.com/user/paul161/media/c 2.jpg.html
http://s805.photobucket.com/user/paul161/media/c 2.jpg.html

 

[paul161201]

Thanks for your replies
How do i fix the new battens to the new apex verge Also how far do i leave the batten from the end of the verge to allow For the mortar bedding?
When the stack is lowered below roof level should i cap off and vent with an air brick on the outside wall?