heatshield – Ask the Chimney Sweep

This is the actual HeatShield repair of a damaged flue system. Here in Cincinnati, when a chimney liner is in need of repair HeatShield can sometimes be installed to resurface the chimney liner without having to install a stainless steel chimney liner which is more expensive. If there are missing mortar joints in the chimney, the HeatShield® Joint Repair System can be an option for repair. You of course must have a professional evaluate the integrity of the chimney to see if a HeatShield® repair is appropriate for your chimney. Missing mortar joints are extremely dangerous and can cause chimney fires. It is not up to code to burn a fire in a fireplace with missing mortar joints. If there are loose or open mortar joints the extreme heat from fires int he fireplace can reach combustibles and cause a chimney fire to occur. It is very difficult to diagnose whether or not you have missing mortar joints if your chimney professional does not run a video inspection of the flue system. The video inspection will be able to spot missing mortar joints that a professional may miss by doing a visual inspection alone after cleaning. Another use of the HeatShield® System is to resurface the entire flue system. Here at American Chimney and Masonry in Cincinnati, If we are going to utilize the HeatShield® System we will resurface the entire flue system, not just the missing mortar joints. If there are widespread cracks in your flue system, multiple mortar joints are missing, or flue tiles are spalling, your chimney professional may deem HeatShield® resurfacing an appropriate repair. The HeatShield® System works by attaching a custom-sized foam applicator is positioned at the bottom of the chimney so that it can be pulled up from the bottom to the top. A tie coat is the first coat to be applied to the flue system. It cleans any remaining dust or other debris and prepares the chimney surface for the HeatShield®. After this primer is applied, HeatShield® Cerfractory® Flue Sealant is squeegeed up the flue system as well. The foam insert smooths the material up through the flue system easily using the "slip cast" system. After the material has had a chance to dry another video inspection is run to ensure that the repair is complete and that there are no holes. The repair must be smoke tight. Remember that not all chimney liner repairs are the same, and for very severe flue system damage often times a stainless steel liner is the more appropriate option. Chimney repair is not anything to mess around with and following professional and manufacturer instruction plus local building and fire codes is absolutely necessary. Please visit the Cecure Chimney website for further information and graphics on the Heatshield® System.