Chimney Flue Extender

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Chimney Flue Extender

Chimney Flue Extender

Chimney Flue Extender

Chimney Flue Extender

Need to offset 2 chimney liner caps adjacent from each other or extend your flue above the roof line? Fits...

Need to offset 2 chimney liner caps adjacent from each other or extend your flue above the roof line? Fits perfectly on to the top plate collar to provide an 18 inch offset / extension.

As low as$128.99

Product Details:

Need to offset 2 chimney liner caps adjacent from each other or extend your flue above the roof line? This little wonder provides an 18 inch offset / extension. Fits perfectly onto the flex liner top plate collar and accepts the Quick Connect Rain Caps at the top of the stainless steel Flue Extender. The quick connect clamps make attaching and removing the Flue Extender a breeze. If you are experiencing smoke or draft issues with a short chimney length, extending the flue can usually help the issue.

A perfect fit every time for your Rock-Flex stainless steel flue liner! Application: Flue extender fits between rain cap and top plate (not included). Choose the diameter size above.

Note: The Flue Extenders should only connect to a flexible liner top plate collar. The female end features a band clamp that measures 7/8" greater than the size you select. Example: Female end of a 6" diameter Flue Extender will measure 6 7/8" to slide over a flexible liner top plate.


Customer Reviews

Based on 4 reviews
Adrian Hill
100% Satisfied

I have called Rockford a few times to ask about their products and they are very friendly and knowledgeable. All of the products I have purchased have been made of great quality. The shipping was quick. Thank you Rockford for being awesome to deal with!!!

great extender flue

Added the extra height that I needed and was easy to install. Shipping was quick.

As described, great product

Product was an exact fit for my 6" stainless steel flue liner kit. The mounting system is exactly what you need to attach to the collar of the top plate i was provided with my original kit. Works well seals good and is easily removable for chimney sweeping. Will recommend!

Extender flue

Was the Extra height I needed to get my clearance above the roof line insulation was very easy

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Our 316Ti flexible chimney liner and chimney liner components have passed the rigorous testing at the Underwriters Laboratories with best in class status and are UL Listed. So if you are looking for UL listed chimney liner sold directly to homeowners, then look no further than Rockford Chimney

Customer Testimonials

Back in July you gave me excellent advice re. sizing/purchasing a flue liner for the chimney associated with my wood stove. I'd like to thank you once agai... More

—AE Northfield, MN

A few weeks ago I ordered a chimney liner system for my fireplace insert. Your salesman recommended the liner system plus the insulating blanket. I just wa... More

—AH Happy customer

Just got around to installing my new smooth flexible liner and deluxe terra cotta cap (wow). The quality of your product is second to none. Very pleased an... More

—B.B. from Massachusetts

Thanks so much for the great tech service from Dennis, very knowledgable, friendly and proffessional.Your website is the best, beats your competition by fa... More

—Bill in Knoxville

Sue and Dennis, I received the final part of my order yesterday (the chimney cap that actually fits over the chimney chase). It looks wonderfu... More


Hello, I was shopping for an fireplace insert and called RCS to ask why they were so much cheaper than my local guy, the reply was " we sell thousand of th... More

—Chris, PA.