Blocking unused chimney.

demanufactured

Whats the best thing to use to block an unused chimney.

When we light the fire (wood burning stove) , in the other room , depending on the wind and temp , we get a bit of smoke coming into the room where the fire is unused , i have some rockwool shoved up there atm and it works but today its freezing and thers no wind.

I lit the stove and went upstairs for half an hour , came back down to the smell of smoke , you cant see it but the smell is strong , the only way to help atm is to open one of the windows to give the chimney a bit of draw , thus making the room cold.

Any suggestions?

northdublin

there is a device that you can get that you shove up into the flue of an unused fire and inflate it. like a bag or a balloon it takes the form and shape of the flue and seals it quite well.
on another note ied investigate why the fumes from one flue are comming back down another. where the stove is there should be a vent in the room to help with the draw, also have you checked the attic while the stove is lighting to see if any fumes are leaking from the flue into the attic space.

demanufactured

It seems to be a ventilation problem causing a downdraught in the room where the fire isnt being used.

It was like that when we moved in a year ago , we used to lght that fire to combat it, but we dont use it anymore as it isnt a real fire(ornamental).

May have to put in a couple of vents in either room.