How HeatShield® Works
When your chimney liner shows signs of deterioration, you face an important decision: do a complete liner replacement or invest in restoration through HeatShield® resurfacing. HeatShield is a proven alternative to traditional chimney relining, where we repair and seal a damaged flue liner from the inside out. At Weststar Chimney Sweeps, our CSIA-certified technicians evaluate your chimney’s condition and recommend the most effective solution – whether that’s HeatShield resurfacing, stainless steel liner installation, or comprehensive chimney repair.
If It’s Mostly Joint Damage
We’ll recommend HeatShield’s® Joint Repair system, which will allow us to repair individual damaged mortar joints until your flue liner is safe again. We apply the HeatShield® Joint Repair system using a specialized applicator blade that allows us to fill and smooth every problem area, crack, gap, and void. Once we’ve made every spot repair, we’ll video scan the entire flue to make sure that the job is complete.
If Your Liner Damage Is More Widespread
HeatShield’s® Resurfacing System is the best choice for flue liners with cracked and spalling tiles. Here, we’ll first layer what’s called a “tie coat” onto the flue to clean, prep and prime it, before applying a roughly quarter-inch layer of HeatShield® sealant to the entire flue with a special applicator. Once that sealant layer is applied, we video scan the flue to check for a smooth and smoke-tight resurfacing job.
Disclaimer: Weststar Chimney Sweeps does not reline chimneys with HeatShield’s CeCure Reling Sleeve.
Restore Your Flue Liner With HeatShield®
Replacing your damaged clay tile flue liner may not be the only way to bring your chimney back to a safer, more efficient state. Weststar Chimney Sweeps also works with HeatShield®, a specially formulated cerfractory sealant that can turn a damaged liner into a smooth, smoke-tight liner that you can be confident in.
In our years of restoring damaged tile flue liners with HeatShield®, we’ve found it to be a highly effective and highly reliable product that can bring a chimney back from the brink. Whether or not your chimney would be best served by resurfacing or relining will depend on the extent of the damage to your current liner – but our technicians can thoroughly inspect your damage and help you sort through your options. Our priority is to provide you with the best possible service, and leave you with a safer, better-functioning chimney. In many cases, HeatShield® is the best product for the job, and can bring years of peace of mind (it even includes a 20-year limited warranty).
HeatShield’s® Relining System Is Another Option For More Thoroughly Damaged Or Unlined Chimneys
We trust HeatShield® when we’re restoring chimney liners, and we’ve also found their Sleeve Relining System to be a great choice for chimneys with more severely damaged or missing liners.
To install HeatShield’s® Sleeve liner, we start by applying a coating of Cerfractory sealant, and then attaching HeatShield’s® CeCure Sleeve (made of ceramic and reinforced with stainless steel). The Sleeve is then sealed with an additional layer of sealant, and the whole flue is video scanned.
HeatShield® can be a great choice for relining chimneys, or restoring a damaged chimney liner. Call Weststar Chimney Sweeps to learn more about it and see if HeatShield® is right for your chimney!
How Do I Know if My Chimney Liner Is Damaged?
Recognizing the warning signs of liner damage helps you address problems before they escalate into more serious safety hazards. Our certified technicians use specialized video inspection equipment to thoroughly assess liner condition, identifying damage that isn’t visible from the firebox or chimney top.
- Visible cracks in flue tiles: Often discovered during routine video chimney flue inspections
- Spalling or flaking mortar joints: Signals moisture infiltration between clay tiles
- Tile pieces in the firebox: Chunks of clay-like material after burning fires indicate active deterioration
- White staining (efflorescence): Appears on chimney exterior or inside firebox, indicating moisture problems
- Excessive creosote buildup: Accumulates more rapidly on rough, damaged liner surfaces
Are there performance issues that may signal a problem? You bet.
- Smoke backing up into your home during fires
- Difficulty starting or maintaining fires
- Persistent odors, especially during humid weather
- Poor draft or reduced fireplace efficiency
Is HeatShield a Chimney Liner or a Coating?
HeatShield functions as a specialized coating system rather than a replacement liner. It restores damaged clay tile liners by creating a new sealed surface over deteriorated tiles. A Cerfractory sealant fills cracks, gaps, and voids, forming a continuous barrier that contains heat and combustion byproducts.
The process begins with a thorough chimney cleaning to remove creosote, soot, and debris. Technicians then apply the sealant using specialized equipment to ensure full coverage. The material bonds to existing tiles, filling imperfections and smoothing rough surfaces. Once cured, it creates a durable surface that improves draft efficiency and helps reduce future creosote buildup.
Unlike stainless steel liner installation, which involves inserting a new liner down the chimney, HeatShield works within the existing structure. This makes it well suited for chimneys with bends, offsets, or dimensions that complicate traditional relining, provided the chimney meets application criteria.
Is Chimney Resurfacing or HeatShield an Option for Older Homes?
Older homes throughout San Diego County, from La Jolla to Escondido, often still rely on original clay tile liners that have deteriorated with age. HeatShield is well suited for these chimney systems when liners show wear but the overall structure remains intact.
Clay tile liners in homes built before the 1980s degrade due to thermal cycling, moisture, and aging. Even San Diego’s mild winters, especially in inland areas, can contribute to cracking and mortar joint damage through freeze-thaw exposure. HeatShield addresses these issues without requiring full chimney reconstruction. The system is also ideal for homeowners who want to preserve the original chimney character. Because it restores existing liners rather than replacing them, HeatShield maintains historic masonry and does not alter exterior chimney appearance.
When installing wood stoves, fireplace inserts, or gas appliances, liner compatibility is essential. A professional evaluation determines whether HeatShield resurfacing meets the requirements of the intended appliance or if a stainless steel liner is necessary for performance and code compliance.
Long story short… Age alone does not disqualify a chimney from HeatShield treatment. Structural condition, extent of damage, and intended use are the determining factors. A detailed inspection identifies whether resurfacing is appropriate or if more extensive chimney repairs are required.
Is Chimney Resurfacing Messy?
Professional HeatShield application requires access to the firebox, but the process is designed to minimize disruption inside the home. Technicians take deliberate steps to protect surrounding areas before work begins, placing drop cloths and plastic sheeting around the fireplace to shield floors, furniture, and nearby surfaces. Most equipment remains within the firebox, with specialized tools extending up into the flue, keeping the work area contained.
HeatShield is applied as a thick, paste-like material, which limits splashing during application. The phase with the greatest mess potential is the required chimney cleaning that occurs beforehand. Removing creosote and debris can generate dust, even with containment measures in place, but technicians use professional-grade vacuums with HEPA filtration to control airborne particles and maintain clean work areas. Once the resurfacing is complete, all protective materials are removed and the fireplace area is returned to its original condition.
The entire process typically takes several hours, including preparation, application, and cleanup. Fireplace use must be paused during the curing period while the material fully bonds to the flue tiles, and clear instructions are provided outlining cure times and when normal use can resume. Compared to full liner replacement, which often involves rooftop work, masonry removal, and extended construction, HeatShield resurfacing remains largely contained within the chimney interior and generally causes far less disruption.
Reach Out to Our Team Today
Determining whether HeatShield resurfacing suits your chimney’s specific condition requires professional evaluation by certified technicians. Weststar Chimney Sweeps has served San Diego County homeowners since 1999, providing honest assessments and expert recommendations based on your chimney’s actual needs. Contact us today to book a chimney inspection and find out which of our chimney resurfacing options is right for your chimney setup.