Most brick or concrete block chimneys are lined with clay flue tiles from when the home was built. Clay flue tiles are fragile, deteriorate over time and use, and have no insulating value. All of these factors can lead to safety concerns and unexpected out of pocket expenses for the homeowner. Instead of installing or replacing tiles that are inevitably going to crack & cause safety concerns, we suggest you consider installing a stainless steel flexible chimney liner system.
Concerns with Clay Flue Tiles
- Crack and deteriorate over time allowing harmful flue gases, such as carbon monoxide, to leak into the home
- Cracked clay tiles are typically deemed unusable per building code
- Clay flues are often the incorrect size for the appliance they’re exhausting
- Do not provide insulating value which leads to an increase in creosote buildup and possibility of chimney fire
- Costly and laborious to install and continuously maintain; will need to be done again down the road
Cracked Clay Flue Tiles
A terra-cotta clay chimney flue is fragile and can crack very easily. The most common reason a clay flue cracks is due to a chimney fire. Even if it's a small chimney fire and you are able to put it out quickly, you should still check the flue for cracks. Extreme temperature change, and even the weather climate, will cause a clay flue to crack. Typically, a cracked clay flue deems the chimney unusable according to building code.
Installing a stainless steel flue liner is a quick and safe way to bring a masonry chimney up to code. A stainless steel chimney liner can withstand temperatures of 2100 degrees Fahrenheit. Our flexible stainless steel chimney liner kits are UL tested and listed for use in masonry chimneys.
Incorrectly Sized Clay Flue Tiles
Clay chimney flues are often the incorrect size for the appliance they’re exhausting. An incorrectly sized flue can cause the appliance to function poorly and improperly. Having the correct size chimney flue for a wood stove will ensure a proper draft. For example, a flue that is too large for a wood stove will make it difficult to get the stove burning. It will take much longer for the flue to heat up and create a draft. This will also cause excessive creosote in the flue because the smoke would be spending more time in the flue, allowing the gas to condense more rapidly and creating more creosote. For gas and oil appliances, the condensation will make it look like it’s raining inside the flue if the flue is too large.
Since clay liners are only available in certain sizes, options are limited. However, stainless steel chimney liners are available in virtually any size to help optimize the efficiency of the appliance. Our stainless steel liner kits are available in a variety of sizes and shapes including round, rectangle, oval, and square. The chimney liner sizing calculator comes in handy when figuring out what size flex liner is best for your appliance.
Clay Flue Tiles Don’t Provide Insulating Value
A common misconception of terra-cotta clay flues is that they provide extra insulating properties. They in fact do not. The only way to keep a flue warmer is to insulate the liner with high temperature chimney insulation. A stainless steel liner wrapped with UL listed chimney insulation is ideal. An insulated chimney liner will also give you a UL tested and listed chimney. This is important to ensure the safety of the chimney.
Clay Flue Tile Maintenance & Warranty
Terra-cotta chimney tiles have a short shelf life and often crack. Relining your chimney with a terra-cotta flue can be expensive and labor intensive, not to mention it is not a lifetime fix and will need to be done again down the road.
It’s very important to understand that both stainless steel liners and clay flues need to be cleaned and inspected. Stainless steel liners require maintenance, but nothing compared to the continued maintenance of clay flue tiles. Stainless steel chimney liners need to be cleaned and inspected, at least annually, but that is dependent on how often the chimney is used and what is venting into the chimney.
Stainless steel chimney liners are user friendly and extremely lighter than a clay flue while also offering a warranty for the flue. A clay chimney flue will never be backed by any type of warranty.
Our stainless steel chimney liner kit is the easiest way to reline a masonry chimney for any appliance. In most situations, a stainless steel chimney liner can simply slide right down the existing clay flue and connect directly to the heating appliance. Even in new construction, a stainless steel chimney liner is the best way to line a brick chimney.