How Do You Extend A Chimney Flue?
If you get smoke drifting into the room when you use your fireplace, it’s an indication you have a weak draft. If your chimney is free of obstructions and your damper is working properly, the problem may be your chimney isn’t tall enough. It should extend at least 3 feet above the roof and be at least 2 feet above any structure within 10 feet, like a dormer or tree. If yours doesn’t, consider extending it with terra cotta flue liners and bricks. Remove the old crown around the flue liner using a ball peen hammer and chisel. Angle the tip of the chisel away from the liner so you don’t damage it and try not to let the debris fall down the flue. Clean the top edge of the flue liner with a wire brush and apply fireplace mortar with a caulking gun along the edge. Position a terra cotta liner extension squarely on top of the existing liner. Build up the walls of the chimney with bricks to the height of the new liner. The wall should end about 8 inches below the top of the flue extension. Bui
