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Having a new chimney liner installed is probably something you haven’t thought much about. The liner’s job, after all, is something you never see: to protect the inside of your chimney. But just as faulty wiring inside the walls can lead to disaster, so can a faulty chimney liner – so let’s take a few minutes to talk liners, and to look at a product called Ventinox.

Chimneys, as you know, are responsible for taking the products of combustion out of your house so that you don’t breathe them, and so that they don’t build up, catch fire, and burn the house down. If your chimney doesn’t have a liner, or if the liner is damaged, you’ve lost the first line of defense. If the chimney walls beyond the damaged or missing liner are damaged (which you also wouldn’t see), then you’ve lost the second line of defense. There is no third line.

The chimneys of newer homes are usually lined, since lining new chimneys has been standard industry practice for some time now. But there are a number of reasons you may still need a new liner, even if you live in a newer home.

  • If you heat with gas, your chimney’s job involves removing a huge volume of water vapor that is produced during combustion. That vapor often condenses in the chimney, and can gradually decay the liner. If the chimney once served an oil or wood-fired appliance, there may be deposits in the flue that will significantly increase the rate of decay caused by this condensation, even if the chimney was cleaned before the gas appliance was installed.

  • If you heat with oil, the combustion products that your chimney has to deal with include sulfur, which, when mixed with water, is highly acidic, and gradually eats away at the lining.

  • And you wood-burners out there already know about the risk of chimney fire, right? A chimney fire can destroy a liner, even if the exterior of the chimney seems unaffected by the fire. Then the next time, you might not be so lucky…

So, what should you do about it? If you heat your home with gas, oil or wood, you should start by having a chimney professional check your chimney system annually, and if your chimney professional discovers that you need a new liner, make the investment.

The good news is that whether you live in an old home or a newer one, even if the liner is – as they say in the chimney industry – toast, your chimney professional can almost certainly re-line the existing chimney, saving you the cost of a complete rebuild and restoring your chimney to proper operating condition.

Among the tools of the trade is Ventinox, a two-part lining system comprised of a flexible stainless steel inner liner, surrounded by a layer of insulation.

Ventinox is a liner system that proves that all liners are not created equal. Most notably, the inner, stainless steel liner is a flexible, seam-welded stainless steel tube.

A what, you ask?

Okay, here’s the deal: Most chimneys, even if they look completely straight, are bent here and there on the inside. This means a rigid liner usually won’t work, because it’s impossible to get the new liner into the bent chimney. What’s needed is a flexible liner that will accommodate the bends in the chimney. Since you can’t bend terra cotta, this requires another material, and stainless steel is the champion.

Manufacturers have basically come up with three designs for flexible stainless steel liners:

  • Thin-wall metal pipe that’s channeled like the end of a soda straw and made of metal soft enough that it will stretch and bend like a straw;

  • Thicker pipe with a loosely-crimped seam that allows the layers to slide over each other as you bend the pipe, compressing on one side of the tube and extending on other side like an industrial metal hose; and

  • Pipe with a corrugated surface that allows it to bend, but with a welded seam.

Ventinox is the third kind. It’s much heavier than the “soda-straw” design, and the seams are welded together instead of merely being crimped, so it is water and vapor-tight as well. It’s the best of both worlds. What’s more, Ventinox is available in sizes ranging from tiny to huge, and can even be custom-shaped for oddball chimneys. In other words, there is a Ventinox product available for pretty much any chimney.

…But there’s more. To fill the space around this superior-quality, seam-welded, heavy duty inner liner is a product called Thermix. It is a lightweight, highly-insulating cement material that is mixed with water and poured into the cavity around the stainless steel inner liner.

You may have read about other types of chimney liner insulation, such as various kinds of ceramic fiber blankets. So, why choose Thermix? The most notable reason is that Thermix, being a wet-mixed insulation that is poured into the chimney cavity, fills every chink and space around the inner liner. It cures to a rigid, non-settling second layer of protection that actually adds structural stability to the entire chimney.

This means that you end up with a chimney that is stronger than it was when you started – and of course the insulation reduces heat transfer to the house, making your home more fire safe. Inside the chimney, the insulation keeps the flue gasses warmer, which results in a better draft, less condensation and less buildup of combustible deposits in the chimney.

One more thing: This isn’t a newbie product that just showed up recently, and might be gone tomorrow. Ventinox has been around the block. These liners have been in the field for over twenty years, and have a proven track record of performance and reliability. By having your chimney re-lined with Ventinox, you are choosing a “known quantity.” So have your chimney checked, and if you need a liner, don’t mess around. Ask your chimney professional to install a Ventinox liner, insulated with Thermix, and have the chimney restored with superior materials, backed by a company with an unmatched track record.

 

This article was prepared from information supplied by ProTech Systems, Inc.