Abstract: An insulating apparatus for mounting within a wall opening and for receiving therein a flue thimble. The apparatus includes a double-walled, cylindrical body member within which the flue thimble is received. The body member defines an annular insulating chamber closed at one end and open at the other to permit air circulation therethrough. A flange extends ouwardly from one end of the body member and is sized to cover the opening of the wall. A cover plate is mounted over the body member and includes a central opening for reception of a vent pipe therein. The cover plate also includes apertures which overlie the open end of the annular chamber to provide air access thereto.

Abstract: A brick control device including a base portion attachable to a wall, a brick flange extending outwardly therefrom for providing vertical alignment of the edge of the brick facing, and a portion extending from the base and including a string flange for attachment of a string holder. Also disclosed herein is a method utilizing a pair of opposed brick control devices with an alignment string spanning therebetween to provide a brick facing which is horizontally and vertically aligned.