Chimney removal check

[johnny2007]

My friend is having his chimney removed below roof level and the roofer doing it said he will seal the flue to avoid drafts.
I wouldn't do that but I wanted to check your advice on this.
I've always closed the lower part of the chimney, at fireplace level without any problem.
Would sealing the top in the loft cause condensation?

 

[blup]

If the whole thing is sealed below, it makes sense also to seal it in the loft, otherwise ventilate throughout including the loft.


Blup