After removing a chimney breast

[Mikey]

I've had a chimney breast removed on 2 floors of my house by a builder, we've had to leave the chimney stack in place as it's a conservation area so have supported the stack with RSJs. The builder hasn't patched up the ceiling yet so when I look up I can see daylight through both chimney pots. What is normal practice after removing chimney breasts, should I ask the builder to put cowls on the chimney to stop the rain dropping in?

Mike

[Andrew Gabriel]

That's probably a good idea as in this case it would directly wet the ceiling. However, the flues _must_ remain vented top _and_ bottom, which might mean fitting airbricks through the brickwork near the top if he caps off the tops of the pots. (I did mine by cutting out half a brick in the loft though to the flue.) If there's only a few feet of flue left, then you can probably get away with ventilating from just one end. Probably not relevant to you, but if possible, avoid venting from a room, as it will draw heat out of the room in winter (when doing heat-loss calculations, you should allow up to a kW lost up a vented flue).

[Stuart Noble]

In theory. In practice I think it's normal to shove rockwool up the flue and seal the bottom

[Nick H]

You can get terracota pots to sit in the top of the chimney pots tha will stop rain getting in but still vent the flue, they are like round "plug" with holes around the sides. You should leave the bottom of the flue open

-- Nick H

[Mikey]

Yes I've seen those pots and was thinking of getting some, but surely you can't leave the bottom of the flue open, it's a bedroom ceiling! It would make the room really cold and anyway wouldn't an air vent on a ceiling look a bit daft? I've never seen a vent on a ceiling before!

[Stuart Noble]

You'd seal the bedroom ceiling and put the vent in the breast above the ceiling i.e. take a brick out. Personally I wouldn't bother with the vent, but I would put insulation up the flue for a foot or so to avoid possible condensation problems