Unused chimney without pot

[Mrxman]

Hi There

We have an unused shared chimney which connects to first floor bathroom. The neighbours chimney side has two chimney pots but on our side there's none.
Our side is partly covered with concrete and partly open. There's no damp and never been a problem but I thought perhaps it should have some sort of cap.

A roofer suggested he could cover it with slate and flaunching but I think that could cause damp if there's no ventilation.

Question 1: Is it advisable to have it capped?
Question 2: What's the best method given there's no chimney pot?

 

[ree]

OP,
Why not post pics showing the chimney stack, & pics of the fire places in the rooms below.
A pic showing the top of the stack - the crown - would really help?
If you go into the loft you might see water stains on the chimney breast - or you might not?

 

[Mrxman]

The house is a typical London Victorian house. As you can see it's a shared chimney with two pots on the neighbours side. I assume the side with no pots is our side.
The fireplace in bathroom is boarded up so no pics

 

[ree]

OP,
I asked for pics of the two fireplaces - 2 x pots = two fireplaces and two flues - for the pics its irrelevant whether the fireplaces are blocked off or not. Pics will show if vents need installing in the blocking?
All redundant flues need venting at the bottom & the top - they also need to be swept.
An air brick can be seen but given the open flue the a/b is doing nothing.
Your flaunching needs to be replaced with new flaunching and, say, two clay ventilation cowls.
Or, given a Victorian stack & the neighbour's existing pots then why not replace with similar two pots with inserted cowls?

 

[Mrxman]

OP,
I asked for pics of the two fireplaces - 2 x pots = two fireplaces and two flues - for the pics its irrelevant whether the fireplaces are blocked off or not. Pics will show if vents need installing in the blocking?
All redundant flues need venting at the bottom & the top - they also need to be swept.
An air brick can be seen but given the open flue the a/b is doing nothing.
Your flaunching needs to be replaced with new flaunching and, say, two clay ventilation cowls.
Or, given a Victorian stack & the neighbour's existing pots then why not replace with similar two pots with inserted cowls?

Thanks for reply.
It was my intention to have similar pots as neighbours but when I got a quote from a roofer suggesting simply putting slate and flaunching I assume he intended to block it up completely so got a bit confused about best practice. As it is I think similar approach to neighbours is a good idea.
Regarding the fireplace on first floor bathroom. It doesn't have any vent so something I'd need to look at. I opened it up some years back and weirdly it didn't look anything like a fireplace, just a small empty void.