Abstract: A method for installing a poured flue adapter within a fireplace is disclosed which comprises providing a plate to be received within the fireplace, the plate having a central aperature within which is positioned a slip connector having a cylindrical portion for connection with the flue of a fireplace insert and a flange which rests against a gasket on the top side of the plate surrounding the central aperture, attaching the flange of the slip connector through the gasket and through the plate, securing two U-bolts to the upper side of the plate for being embedded within a cementitious material, and positioning the plate within the chimney and applying the cementitious material to the upper side to secure the plate assembly in position. A poured flue adapter useful in the foregoing method is also described.