You have two options for insulating your chimney liner. You can use an insulation wrap (pictured to the left) or you can use a poor down insulation. First and foremost it is always a good idea to insulate your chimney liner. If you are installing a chimney liner for a solid fuel application such as wood or coal, you will definitely want to insulate. If you are venting gas or oil insulation is optional.
If your existing terra-cotta flue liner doesn’t have much space left after the liner is installed you may opt to use a poor down insulation. The most common choice for insulation is the wrap if clearances allow for it. Insulation wraps commonly come in .25 and .5 inch thicknesses.
Instructions chimney liner insulation installation:
Using Insulating Blanket Wrap
1. Make sure the bottom termination connector is installed. The liner must be insulated all the way to the bottom of the connector.
2. Determine the length of insulation needed and cut.
3. The insulating wrap must overlap along its length by a minimum of 1 inch. To ensure you have the proper width of insulating wrap, multiply the liner diameter by 3.14 plus one inch for overlap. You may trim the width of the insulation to this amount but is not necessary. If the overlap is more than one inch you may have difficulties with clearance.
4. With the foil side of the insulation facing down, lay it out on a flat surface.
5. Set the liner in the center of the insulation.
6. Begin wrapping the insulation around the liner, leaving at least a one inch overlap on the seam. You can use the spray adhesive to help keep the insulation in place. Use the foil tape to secure the seam at one foot increments.
7. Once the insulation is in place, lay one continuous vertical length of tape on the entire seam.
8. Unroll the wire mesh and encapsulate the full length of liner including the bottom connector. Use one hose clamp to secure the mesh to one end of the liner. Now on the other end of the liner, pull the wire mesh until it retracts and fits tightly on the liner. Use another hose clamp to secure the mesh on the pulling end. Cut away excess mesh. You may take the stainless steel locking wire and spiral wrap the wire mesh to help keep it in place during installation .
9. The liner is now ready to install.
Using Insulating Mix
Note: Insulation mix is poured down the chimney after the liner is installed.
1. Empty insulation into a wheelbarrow or mixing box. Add the appropriate amount of water per bag of insulation mix. When the material is damp, but still granular you have achieved proper consistency.
2. Distribute the insulation mix evenly around the liner. Make sure to center the liner in the flue.
3. Vibrate the liner as you continue to pour the insulation down the flue around the liner.
4. All heating appliances or fireplaces can be used after insulation process is complete. You do not have to let the insulation set. Make sure to keep flue gas temperatures below 700 degrees F for a period of three weeks.