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10% Off 316 Stainless Steel Chimney Liner Kits

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chimney liner square

Square Stainless Steel Flue Lining Kits

Rock-Flex 316Ti Stainless Steel Square Chimney Liner & Components Kit
APPLICATIONS: Wood, pellet, gas, oil, and coal burning appliances

Note: Square chimney liners and components are custom made to your specifications, and are not refundable. Please call us if you have any questions.

How this page works:

  • Select liner size and length in step 1.
  • Select kit components for your application in steps 2-5.
  • Click on Add To Cart below for total cost.

Do You Really Need a Square Liner?

Even if your chimney flue is not round, in some circumstances a round liner will better meet your needs. Round liners are more cost-effective and easier to install. If you have questions, please give us a call at 1-866-708-2446. We'll be happy to help you.

Step 1: Select your 316Ti Square Chimney Liner:   (Click here for help with liner size.)

Rock Flex Square Chimney Liner

316Ti .006 stainless steel square chimney liner. Air and water tight. This flue liner has 7 ply seams, rated number one in the industry for strength. Our square chimney liners are UL listed in the United States UL1777 and ULC365 in Canada. They are made of the very best, hand selected, prime stainless steel material available on today's market.

The sizes listed in the drop down box below are square O. D. (Outside Dimensions) and pricing is per foot. See our Square Liner Conversion Chart.

Square chimney liner to liner connector

You will need a stainless steel square to square liner connector if you are purchasing more than 25 feet of liner, as it will be shipped in separate lengths. (25 feet is the maximum length that can be shipped.) Please order one liner connector for each additional length.

Square to Square liner connector:

Step 2 - Select your stainless steel Tee, Appliance Connector or Bottom Plate:

square Tee with round horizontal snouttee connector setup small
Square Tee Connector and Cap - $214.99

Flex Liner Snout Adapter - for 5.5 in. to 8 in. liners

Square Tee and Tee Cap

The Tee has a square shaped body and is attached to the bottom of the liner prior to dropping it down the chimney flue. The 10" long horizontal snout of the tee is round and fits into the thimble of your chimney. See the green wood stove picture at left for a visual aid as to how this 2 piece tee is installed; you need to click on the picture. We will match tee to the correct size based on the liner size selected in step 1.

The Snout Adapter reduces the tee snout diameter, allowing you to attach a flexible chimney liner without having to crimp the tee snout. For 5.5 in. to 8 in. liners only.
snout adapter with tee connector
Snout adapter shown with tee connector (not included).

square to round adaptersetup
Square to Round Connector

Square to Round Vertical Liner to Insert/Appliance Connector

Mates a drip less connection between square flex liner to the round opening or vertical pipe on your appliance. (We will match square to round connector to the correct size based on the liner size selected in step 1.)

square chimney liner bottom platesetup
Square Bottom Plate - $99.99

Square BottomPlate for Standard Fireplace Bottom Termination

Flat bottom plate measures 18" x 18" with a square collar to accept the square chimney liner at the bottom to terminate the liner at the top of an existing fireplace.

The 18"x18" flat bottom plate can be trimmed down with a pair of good tin snips. With this square quick connect bottom plate all you will need to do is tighten down the screw on the outside of the collar and your liner is clamped in place at the bottom terminating the old flue of your chimney. We will match square bottom plate to the square liner selected in step 1.

Mesh Bottom Plate
Square MESH Bottom Plate - $57.99

Square Mesh Bottom Plate for standard fireplace bottom termination

Great for transitioning from a liner to the fireplace smoke chamber. Our 18"x18" mesh bottom plate features a "quick connect" collar to secure the liner. Moldable mesh allows for a perfect finish with Everguard Refractory Cement.

We will match the bottom plate to the square liner selected in step one.

Step 3: Select your stainless steel Top Plate:

square chimney liner top plate
Square Flat Top Plate
Flat Top Plate 18"x18" - $99.99

terra cotta top plate
Square Terra Cotta Top Plate
Terra Cotta Top Plate 8"x8" - $129.99
Terra Cotta Top Plate 8"x13" - $134.99
Terra Cotta Top Plate 13"x13" - $139.99
Terra Cotta Top Plate 13"x18" - $144.99
Terra Cotta Top Plate 18"x18" - $149.99

Choose our Flat Top Plate if you will be screwing the top plate to the top of your chimney. If you have clay tile at the top of your chimney, you will want to select a Terra Cotta Top Plate.

Both styles have a square collar design to accept the square chimney liner you selected in step 1. Both top plates come with the quick connect system, simply tighten down the screw on the outside of the collar of the top plate to secure the liner to the top of the chimney.

The Flat Plate can be trimmed down with a good pair of tin snips. The Terra Cotta Top Plate comes with stainless steel screws to secure the top plate via a friction fit. See our Terra Cotta Top Plate Sizing Chart.

We will match your square top plate collar to the square liner selected in step 1.

Step 4: Stainless steel Rain Cap:

Square chimney liner rain cap
Square Rain Cap - $139.99
Yes, I will need a rain cap
No, I will not need a rain cap

Quick connect square rain cap with screen, wind guard, and quick connect clamp system.

The rain cap fits on the outside of the top plate collar. Once in place all you need to do is tighten down the clamp that is already on the rain cap.

We will match the rain cap to fit your top plate.

Recommended Accessories

Insulation Kits
Insulation Kit

Top Plate Silicone Adhesive
Silicone Adhesive

We offer only the best protection for you and your home. Air and water tight chimney liners with seven ply seams that lock moisture and flue gases in your chimney liner and keeps them from leaking into the home.

Guards Against Corrosion - Certified Rock Flex stainless steel chimney liners protect against hostile acids which deteriorate masonry clay tile chimneys.

What About Creosote? - Our chimney flue liners do not allow creosote to leach though the liner unlike masonry, clay tile flues, or liners not made of prime stainless. Creosote can catch fire, and lead to a house fire. Thanks to Rock Flex, this harmful creosote is minimized and contained.

Seals Off Carbon Monoxide - When it comes to safety our flexible chimney liners will protect the structure of your home from moisture damage and the very real potential of carbon monoxide poisoning.

UL listed in the USA and CANADA - Our Stainless Steel Chimney Liners and Components are UL tested and listed to USA UL1777 standard, & Canada ULCS635 Underwriter Laboratories. UL is the leader and most recognized in the United States, don't settle for less.

Lifetime / Transferable Warranty - The best warranty anywhere, transferable to new homeowner if you decide to sell. You're going to feel good about this purchase, plus you're adding value to your home with our chimney parts.

316Ti Liners - A unique titanium alloy designed to resist flue acids and the extreme stresses of hot and cold cycles. 316Ti Stainless Steel can be used with fuels such as wood, pellet, gas, oil, and coal. It can withstand multiple heating cycles up to 2100 degrees.

Rock Flex oval chimney liners are .006 thick, which exceeds the industry standard, giving you more for your money.

To learn more about insulation blankets and thermo insulation Click Here

Rockford carries a complete selection of chimney liner supplies. Our Chimney Liner Kits, Chimney Liner Insulation Kits, and all chimney liner kit components are premium stainless-steel, they are 100 percent manufactured in the USA. Buy chimney liners online at Rockford Chimney Supply and you are guaranteed to be getting the best chimney liner supply and lining system available on today's market. Our service, price, & quality is unmatched, anywhere. Canadian customers welcome.

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