Chimney Fire

[firecracker_77]

Are chimney fires as dangerous with triple wall and double wall pipe these days?

It seems like the class A stainless is designed to take high temps for 15 minutes or so. Wouldn't the fire die out by then?

 

[Grisu]

Are car accidents as dangerous with airbags, side impact beams, crumple zones and seat belts? No. Do I want to be in one? Certainly not.

 

[firecracker_77]

Are car accidents as dangerous with airbags, side impact beams, crumple zones and seat belts? No. Do I want to be in one? Certainly not.

I certainly agree and I'm not trying to be flip. I'm just thinking it through. Doesn't mean I'm not cleaning my chimney.

 

[Beer Belly]

I don't know the true answer, I just know that I wouldn't want the excitement of it happening, and regardless of anything, after a Chimney fire, I'd still have everything checked. I would imagine that if you were to have a Chimney fire, having triple wall would be a good thing to have.

 

[Jags]

Most MFG's require an inspection and possible replacement after a chimney fire. With that said - I would still call them dangerous. Maybe not as catastrophic as in the past, but definitely dangerous.

 

[oldspark]

Yes they are as dangerous as they ever were, a well made mason chimney with a liner could take a lot of heat also, sometimes it the crap spewing out of the chimney that causes issues.

 

[Dustin]

Dangerous, yes. Do they burn down houses like so many structure fires I used to respond to? Not as often.

In the old days the chimney fire would start in the masonry chimney and work it's way into the walls, burning most if the house.

Now, it's generally contained in the liner or stove pipe. But something to remember, if there is a tiny pin hole, a weak spot in the steel, anything that may not be harmful under normal operating conditions, could prove catastrophic in the event of a fire

 

[oldspark]

"In the old days the chimney fire would start in the masonry chimney and work it's way into the walls, burning most if the house"
I agree but the chimneys in some cases were not built well as in the case of a single wall cob job, I believe the rating on a ceramic liner is almost the same as the metal liner if not a little higher (not sure about that, it was at one time).

 

[smitty81]

I have a question.............

I don't have a chimney per say but a flu. I'm guessing a fire in my pipe is just as dangerous as a chimney fire?

Also, If one ever did have a fire in their chimney or flu, how would you know short of walking outside and looking at your roof?

I've always been curious as to what to watch for inside.

 

[Grisu]

I have not experienced it myself but from some descriptions here:
A chimney fire will suck a lot of air through your stove; supposedly it sounds like a jet. Some also report a crackling sound in the flue. Do you have a stainless steel liner?

 

[oldspark]

I have a question.............

I don't have a chimney per say but a flu. I'm guessing a fire in my pipe is just as dangerous as a chimney fire?

Also, If one ever did have a fire in their chimney or flu, how would you know short of walking outside and looking at your roof?

I've always been curious as to what to watch for inside.

Whoa- what are you saying, you only have a flue pipe, tell us what you got.

 

[smitty81]

I think I may be using the wrong terms or im posting on the wrong page.

this is what I have.

 

[oldspark]

So you have a flue going up to class A pipe which is a chimney. So you have the very same thing that most of us have so the discussion works for you.

 

[smitty81]

ok, I'm sorry.........I'm not real sharp with the proper terminology.

 

[oldspark]

No problem, I edited my post to reflect that is what most of us have so you have the same concerns we all have.

 

[begreen]

The pipe going from the stove to the support box is called the "connector". It can be single or double wall pipe. The pipe above the support box and through the roof is the "chimney" and must be class A high temp pipe.

 

[jharkin]

My father had a chimney fire about 10 years ago. I wasn't there but he described it as the jet engine sound... shook the whole house.He was extremely lucky because in putting it out and repairing the damage they discovered that the builder had cheaped out in the 1960s and built their chimney 3 sided (I had never heard of such a thing before the incident, no idea if it was ever code legal)

The other way chimney fires would burn down houses, especially in the 19th century and earlier, was when flaming embers coming out of the stack fell on wood shingle/shake roofs.

 

[firecracker_77]

Yeah...I would be scared. I wonder how long creosote would take to burn off?

 

[firecracker_77]

My father had a chimney fire about 10 years ago. I wasn't there but he described it as the jet engine sound... shook the whole house.He was extremely lucky because in putting it out and repairing the damage they discovered that the builder had cheaped out in the 1960s and built their chimney 3 sided (I had never heard of such a thing before the incident, no idea if it was ever code legal)

The other way chimney fires would burn down houses, especially in the 19th century and earlier, was when flaming embers coming out of the stack fell on wood shingle/shake roofs.

I think they were different designs back then without the stainless, so easier to trap creosote. And no cap on the top which would catch some embers. And people were burning a lot more wood back then too. I read that in colonial times it was something like 30+ cords a year which I can't even wrap my brain around.

 

[Ram 1500 with an axe...]

Nice gun rack..

 

[jharkin]

I think they were different designs back then without the stainless, so easier to trap creosote. And no cap on the top which would catch some embers. And people were burning a lot more wood back then too. I read that in colonial times it was something like 30+ cords a year which I can't even wrap my brain around.

Back "then" things where very different for sure. Chimneys where almost universally brick or stone up through the Civil War and later and unlined. So you had the rough texture of exposed brickwork inside the flue to grab buildup. Colonal era fireplaces where big square boxes, kitchen ones being large enough to walk into, and just opend up to the flue with no damper or smoke shelf (they used doors like Joful has, or fireboards to cover the opening when unused).

A big center chimney colonial or saltbox in New England might have as many as 4-6 fireplaces plus some beehive ovens on two floors vented through a single chimney, and the individual flues where typically only separated by a wall of one brick thickness, then they all joined together at the attic level into one giant single flue. The outer wall of the chimney was probably two bricks thick at the roof and significantly thicker as you went down, but also it was common practice to use center chimneys to support framing beams - so you might not have much thickness of masonry between flue gasses and woodwork.

When wood stoves started to appear early installs where done like "slammers" just putting a short length of stovepipe into a fireplace flue. By the Greek revival era (1830s-50s) stoves are common enough that you start to see new houses built with no fireplace at all, just a small chimney with stoves attached. Then in the Victorian days (1870s on) fireplaces come back but for entertainment rather than heat, and many of them designed for coal.

Over the years many old fireplaces where modified, often bricking in a large box colonial hearth to convert it to a slant sided rumford style with an iron damper and smoke shelf in the early 1800s, and then in the Victorian era bricking them in even smaller to convert to coal. Not a lot of 1700s houses still standing today that have never been modified.

I have seen a number of 18/19th century vintage houses with brick and stone caps on the chimneys but I suspect many of those are later modifications.

 

[smitty81]

I'm a relatively new guy so thank you for answering my noob questions.

I have another noob question here.

What would be the proper procedure to kill a chimney fire?


I know restricting the air available to the fire is the main goal but short of closing the air damper, what else?

 

[Ram 1500 with an axe...]

Ok, if I had a chimney fire I am thinking that there is 2 places for it to go, back down into my insert or through the top of the chimney. Am I incorrect to think that if I did have a fire, it would just burn out? Thanks all for any info... insert with closed door is on the other end...

 

[jharkin]

Call 911.
Leave house.


I keep a chimfex by the stove and my last act before running out the door would be to toss it into the firebox, but Ive never had to use it so I cant comment on how effective it is.

 

[smitty81]

Call 911.
Leave house.


I keep a chimfex by the stove and my last act before running out the door would be to toss it into the firebox, but Ive never had to use it so I cant comment on how effective it is.

I was thinking of buying a few of these just in case. I'd throw two in to better my chances.