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petefritz
Chimney Liners

My chimney unquestionably need to be rebuilt from the roofline on up (cracked cap and crumbling bricks/mortar). In getting quotes, some companies wanted to use a stainless steel liner while others would just reline with new flue tiles.
This is a wood-burning fireplace only (no water heater or furnace venting up it). Do I need the pricier stainless steel liner (quotes are anywhere from $400-1000 higher with this option)? Or are new flue tiles OK? Will one last longer than the other?
Thanks!

rdesigns
Re: Chimney Liners

When a masonry chimney that serves only a wood-burner goes bad, it is almost always due to weather affecting the masonry, rather than flue gas condenstation on the inside, such as is common with chimneys serving gas appliances.

This is because wood fires are plenty hot to prevent condensation from happening inside the chimney, whereas gas appliances create a lot of water vapor from burning hydrogen, and the vapor tends to condense inside the chimney, and the condensate is acidic, which attacks the mortar along with wetting the mortar to set up freeze-thaw cycles that break down the masonry over years. Burning wood is more of a carbon-burning process than a hydrogen-burning process, so not nearly as much water vapor is produced.

Your description is consistent with this, because you're seeing deterioration on the part exposed to weather.

What this means is that you need a knowledgable mason experienced in rebuilding masonry chimneys to withstand the long-term effects of weather.

A SS liner will not protect the chimney from weather--it would protect the chimmey from gas appliance flue gases, but that's not the source of your trouble.

petefritz
Re: Chimney Liners

rdesigns, thanks! I think you answered my question.
I believe the bad cap set this chimney up to fail (albeit, after 30 years). The cap did not overhang the brick, and then they used the brick as the drip edge with a slight inset after the second row of bricks from the cap. This allowed moisture into the bricks and the freezing WI weather caused the brick/mortar breakage. I'm leaning towards no SS liner as the added cost will do nothing but line the contractor's pocket (no pun intended).
I only have owned this house since last June and am taking the time to fix the last owner's neglect and want to do it right (not just cheap).

bp21901
Re: Chimney Liners

Due to the heat make sure they use refractory cement when setting the flue liner.

canuk
Re: Chimney Liners
rdesigns wrote:

When a masonry chimney that serves only a wood-burner goes bad, it is almost always due to weather affecting the masonry, rather than flue gas condenstation on the inside, such as is common with chimneys serving gas appliances.

This is because wood fires are plenty hot to prevent condensation from happening inside the chimney, whereas gas appliances create a lot of water vapor from burning hydrogen, and the vapor tends to condense inside the chimney, and the condensate is acidic, which attacks the mortar along with wetting the mortar to set up freeze-thaw cycles that break down the masonry over years. Burning wood is more of a carbon-burning process than a hydrogen-burning process, so not nearly as much water vapor is produced.

Your description is consistent with this, because you're seeing deterioration on the part exposed to weather.

What this means is that you need a knowledgable mason experienced in rebuilding masonry chimneys to withstand the long-term effects of weather.

A SS liner will not protect the chimney from weather--it would protect the chimmey from gas appliance flue gases, but that's not the source of your trouble.

That depends on the moisture content of the wood burned and how hot of a fire is being burned. Creosote is a result of too much condensation either from high moisture and or dampened fire --- which is caustic to liners.

elishkiya
Re: Chimney Liners

Chimney liners offering Chimney liner kits & parts including rigid chimney liners, aluminum chimney liner kits, easy flex & heavy flex chimney liners and other liner tools.

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