Professional-Grade 6-Inch Stainless Steel Chimney Liner

Professional-Grade 6-Inch Stainless Steel Chimney Liner Kit: Denver’s Trusted Solution

When homeowners in Denver need a reliable chimney relining solution, the Flex-All 6-inch by 25-foot kit delivers professional-grade performance at a practical price point. As someone who has installed hundreds of liner systems across the Denver metro area—from Park Hill bungalows to Littleton split-levels—I can tell you that this kit provides everything needed for a safe, code-compliant installation.

Why Denver Homeowners Choose This System

This single-ply 316 stainless steel liner offers the flexibility required for navigating the offset flues common in Denver’s older homes while maintaining the durability necessary for our climate extremes. The 0.006-inch thickness strikes the right balance between flexibility for installation and strength for long-term performance. I’ve used this exact system in homes throughout Denver County, and it consistently delivers reliable venting for wood stoves, gas fireplaces, pellet inserts, and high-efficiency furnaces.

The 316-grade stainless steel matters more than most homeowners realize. Unlike 304 stainless, the 316 alloy contains molybdenum, which provides superior corrosion resistance against the acidic condensation produced by modern high-efficiency appliances. Denver’s dry climate can amplify this issue during startup cycles, making the upgraded alloy a wise long-term investment.

Complete Kit for Professional Results

This kit includes all the components necessary for a proper installation: the 25-foot liner, a two-part tee with a cap for cleanout access, a 4-inch by 14-inch top plate with a rip collar, a round termination cap, all necessary fasteners, detailed installation instructions, and warranty documentation. The inclusion of a complete tee assembly—often sold separately in competitor kits—saves approximately $80 to $120 in additional parts.

The 14-inch top plate fits standard masonry chimney tiles commonly found in most Denver-area homes built between the 1950s and 1990s. The drip collar prevents water infiltration at the chimney crown, addressing one of the most common failure points I encounter during inspections. The round cap provides rain and animal protection while maintaining proper draft, critical at our elevation, where draft margins are already tighter than at sea level.

Versatile Applications Across Denver Homes

This 6-inch diameter handle is suitable for most residential heating applications. I’ve successfully installed these liners for:

Fireplace Inserts: Wood-burning and gas inserts in living rooms throughout Washington Park, Cherry Creek, and Highlands neighborhoods. The flexible liner navigates around damper assemblies and smoke shelves that would block rigid pipe.

High-Efficiency Furnaces: Modern condensing furnaces require Category IV venting. The stainless steel resists the acidic condensate these units produce, preventing the premature failure I’ve seen with aluminum liners.

Pellet Stoves: The smooth interior surface minimizes creosote buildup, allowing for efficient venting of the fine ash produced by pellet fuel. I installed one last month in a Lakewood Ranch home, and the homeowner reported noticeably improved stove performance.

Oil Appliances: Though less common in Denver, oil furnaces and boilers benefit from stainless steel’s resistance to sulfuric acid formed during combustion.

Installation Considerations for Denver’s Building Code

Denver’s building department requires permits for chimney liner installations when they serve heating appliances. The code, based on the International Residential Code with local amendments, mandates proper sizing, adequate clearances, and appropriate termination height. This kit meets these requirements when installed in accordance with the manufacturer’s specifications.

The 25-foot length suits most single-story and many two-story homes in Denver. Ranch homes in areas like Green Valley Ranch or Montbello typically have chimney heights ranging from 18 to 22 feet, providing sufficient material for proper top-plate connection and lower tee installation. Two-story homes may require additional liner length—something we determine during our initial inspection.

Insulation, although not included in this basic kit, is often necessary for Denver installations. When the liner runs through an exterior chimney or when clearances to combustibles are tight, the building code requires insulation wrap. We typically add half-inch ceramic fiber insulation, which adds $275 to $450 to the project cost, depending on chimney height.

Professional Installation vs. DIY

While this kit includes detailed instructions for experienced DIYers, I strongly recommend professional installation for several reasons. First, Denver requires permits and inspections—work performed without permits creates liability issues and can complicate future home sales. Second, proper sizing and clearance calculations require an understanding of appliance specifications, altitude correction factors, and code requirements. Third, working on roofs in Denver’s weather conditions presents safety risks, especially during our unpredictable spring and fall seasons.

The professional installation of this kit typically costs between $1,800 and $2,400, which includes the liner kit, insulation (if required), permits, labor, and coordination of the final inspection. This investment ensures code compliance, optimal performance, and manufacturer warranty validation—most warranties require professional installation to remain valid.

The Lifetime Warranty Advantage

The lifetime warranty that backs this product reflects the manufacturer’s confidence in the materials and construction quality. This warranty covers defects in materials and artistry for as long as you own your home—exceptional coverage in an industry where 10 to 20-year warranties are standard.

However, warranty coverage requires proper installation, appropriate application, and regular maintenance. Annual chimney inspections, which we provide starting at $199, verify the liner remains in good condition and identify any issues before they compromise safety or performance. I’ve seen homeowners lose warranty coverage due to improper installation or lack of maintenance—preventable situations that proper professional service eliminates.

Why We Stock and Recommend This System

After testing dozens of liner systems over my years serving Denver homeowners, this Flex-All kit consistently delivers the reliability our clients deserve. The made-in-USA manufacturing ensures quality control and parts availability. The 316 stainless steel provides the longevity our climate demands. The complete kit eliminates the frustration of ordering multiple components from different suppliers.

I installed this exact system in my own home when I relocated to Aurora three years ago. My wood-burning insert vents ideally through this liner, drawing cleanly from the first match and maintaining efficient combustion throughout extended burn cycles. That personal confidence translates to the recommendation I give customers throughout the Denver metro area.

Getting Started with Your Liner Installation

If you’re considering chimney relining—whether for a new appliance installation, masonry chimney deterioration, or conversion from wood to gas—this kit provides the foundation for a successful project. The first step involves a thorough inspection to verify sizing, measure chimney height, assess clearances, and identify any preparatory work needed before liner installation.

Contact us at (720) 207-9232 to schedule your chimney evaluation. We’ll determine if this 6-inch kit suits your application or if you require a different diameter. We’ll assess insulation requirements based on your specific installation, provide a detailed written estimate covering all project costs, and coordinate permits and inspections to ensure complete code compliance.

Our location at 12894 E Villanova Dr in Aurora positions us to serve the entire Denver metro area quickly and efficiently. Whether you’re in downtown Denver, the southern suburbs, or the eastern plains communities, we deliver the same professional service and attention to detail that’s earned us hundreds of five-star reviews from satisfied customers.

Visit our website to learn more about chimney liner installation, browse our complete service offerings, and read testimonials from Denver-area homeowners who’ve trusted us with their chimney needs.

This Flex-All 6-inch stainless steel liner kit represents a wise investment in your home’s safety and efficiency. With proper professional installation and regular maintenance, it will provide decades of reliable service—protecting your family while optimizing your heating system’s performance through countless Colorado winters.