Many people, particularly those who live in Victorian properties, will have numerous chimney stacks with multiple flues. Most of these will have, over time, been blocked off and are no longer in use. But what should be done with them? The best thing to do with an unused chimney, is to cap it off at the top of the stack. This will stop any rain ingress, animals or debris from getting into the stack and potentially causing a problem. However, their still needs to be a flow of air through the chimney to prevent damp from occurring both in the stack itself and any rooms that come off of it. The best way to do this is to purchase a chimney capper with ventilation which will cap off the stack from the pot itself. If there isn't a chimney pot and the top of the chimney has been cemented over, you can insert an airbrick into the side of the stack near the top which will also provide ventilation for the chimney. Please call Flue Supplies 0844 800 6586 for more information on our Chimney Cappers. http://bit.ly/15THyL9