All the heat goes up the chimney myth

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To be fair, where is the "paragraph" that one is exempt from bringing a system up to the stipulations of code if the system is already existing and not being altered? If that paragraph is "in the code" (e.g. at the end), then one is "up to code" in a case like this. The exemption is part of the code. That's how law works imo.

Hence, this is a matter of semantics.

That said, the latest code requirements are without a doubt safer.
 
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stoveliker said:
To be fair, where is the "paragraph" that one is exempt from bringing a system up to the stipulations of code if the system is already existing and not being altered? If that paragraph is "in the code" (e.g. at the end), then one is "up to code" in a case like this. The exemption is part of the code. That's how law works imo.

Hence, this is a matter of semantics.

That said, the latest code requirements are without a doubt safer.
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No a statement like that would mean that setup is exempt from code not that it meets code.
 
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bholler said:
No a statement like that would mean that setup is exempt from code not that it meets code.
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My point is that you appear to read the legal text as (limited to) "a set of requirements".
I believe that is (legally) too narrow an interpretation of "code". I believe "code" is "a set of requirements including when they apply". (As in: flues need to be xyz for fireplaces, whereas flues need to be zyx for wood stoves - that is a requirement and when it applies. Evidently the xyz flue requirement does not apply to stove set ups.)

As the "existing builds don't have to ..." is exactly that, a limitation of applicability of the set of requirements, it is code imo.

It does not meet the latest (and most safe) requirements, but it does meet code.

"What is code" - is the debate you had with the OP. And that is, a semantics debate I think.

Until I'm (happily) corrected by a lawyer...
 
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stoveliker said:
My point is that you appear to read the legal text as (limited to) "a set of requirements".
I believe that is (legally) too narrow an interpretation of "code". I believe "code" is "a set of requirements including when they apply". (As in: flues need to be xyz for fireplaces, whereas flues need to be zyx for wood stoves - that is a requirement and when it applies. Evidently the xyz flue requirement does not apply to stove set ups.)

As the "existing builds don't have to ..." is exactly that, a limitation of applicability of the set of requirements, it is code imo.

It does not meet the latest (and most safe) requirements, but it does meet code.

"What is code" - is the debate you had with the OP. And that is, a semantics debate I think.

Until I'm (happily) corrected by a lawyer...
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I have sat through many many hours of very boring classes about code applicability and compliance taught generally by lawyers. An exemption does not nessecarily mean compliance.
 
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ctyankee said:
Three feet from the fire and it is at 126 degrees fahrenheit (127 before I turned it for photo). This is a small fire. I've had the temp gauge there less than 10 minutes. Heat is going up the chimney. But there is a lot of heat to spare. How hot is it 3 feet from your stove?
.
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The difference is mine reads 70* 50 feet away. My house is 66x28. 1848 square feet. It will read 64 when I get up, (9*f outside) and come right back up to 70 or more all day. There are no other heat sources. No thermostat or central heat system. My stove also has an oven, 20x45 inch cooktop, and 25 gallon hot water tank.

It doesn’t matter what a stove reads 3 feet away, because it radiates in all directions. Wouldn’t that temperature you measure in one direction be x 4 all around a stove?? If the BTU radiating in one direction is 20,000, the total would be 80,000 going directly into the air. If your fire was radiating the same in all directions it would be a comparison.

Next is the heat loss through your masonry. Is the fireplace on an outside wall? Does it get warm on the outside? How about up through the roof? They are built to radiate heat from the mass into the building. But they also radiate upward and out the roof. An insulated prefab chimney doesn’t waste that. Only what goes into the chimney is waste.
As my fire dies the heat produced stays in the house, it doesn’t rise up the chimney. Ben Franklin had a good idea to put cast iron in the fireplace to radiate more heat into the home. After you try that, try a Fisher and see how much better it works with a blower. Then try a new secondary burn Insert. The only problem is, you would need to bring the vent system up to code because it no longer looses so much heat up the flue, it can produce creosote. That’s the reason it needs to be brought up to code, because you’re no longer using it as it was built.

[Hearth.com] All the heat goes up the chimney myth
 
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The point is not whether the whole home can be heated. The point is how much wood is needed for that.
I heat my home (inefficiently, thru the basement, meaning it's 80+ there when it's below 30 outside to keep my main floor around 68) with two loads of my firebox per day. Period. Nothing else. (That's a 3 cu ft firebox - I presume it'll be more when it gets to be consistently below 20 F, I don't know.)

Heating a whole home with a fireplace may be possible (I don't know, as I refuse to try something scientifically shown to be inefficient), but you better have a large woodshed to do so...
 
On christmas we had the fireplace going for most of the day and it did keep the downstairs quite toasty around 82 in the living room and 76 in adjacent rooms. However I was feeding it 4 splits an hour, whereas I usually feed my stove 4 splits every 8 hours.
 
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stoveliker said:
The point is not whether the whole home can be heated. The point is how much wood is needed for that.
I heat my home (inefficiently, thru the basement, meaning it's 80+ there when it's below 30 outside to keep my main floor around 68) with two loads of my firebox per day. Period. Nothing else. (That's a 3 cu ft firebox - I presume it'll be more when it gets to be consistently below 20 F, I don't know.)

Heating a whole home with a fireplace may be possible (I don't know, as I refuse to try something scientifically shown to be inefficient), but you better have a large woodshed to do so...
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It is not possible to heat an entire home with a single fireplace unless that home is very small.
 
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Our cold climate ancestors must of knew a way to stay warm all winter long with a fireplace otherwise you lawyers, insurance men and code enforcers wouldn't be here....LOL
 
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snobuilder said:
Our cold climate ancestors must of knew a way to stay warm all winter long with a fireplace otherwise you lawyers, insurance men and code enforcers wouldn't be here....LOL
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Of course they did, that's why fireplaces were invented. Still doesn't mean it's better than what we have today
 
snobuilder said:
Our cold climate ancestors must of knew a way to stay warm all winter long with a fireplace otherwise you lawyers, insurance men and code enforcers wouldn't be here....LOL
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No, average life expectancy was far lower. Why? In part because a boatload of people just died in house fires.
(And they did produce us because they had to stay warm together at night....)
 
snobuilder said:
Our cold climate ancestors must of knew a way to stay warm all winter long with a fireplace otherwise you lawyers, insurance men and code enforcers wouldn't be here....LOL
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They had multiple fireplaces in homes and they weren't warm. They just didn't freeze
 
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stoveliker said:
No, average life expectancy was far lower. Why? In part because a boatload of people just died in house fires.
(And they did produce us because they had to stay warm together at night....)
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That's just plain silly. They died from hard work and little healthcare .
 
There are plenty of calculators out there that can calculate chimney cfm in relation to ht, temp difference top to bottom, size.
An airtight stove has plumbing that restricts that flow. Somewhere I saw a figure of 5cfm as a typical airflow for something like I have (F500).
A fireplace has no such restrictions.
I know the old farmhouse back home sure was hot by the fireplace, and the rooms at the far end of the house had frost on the walls.

[Hearth.com] All the heat goes up the chimney myth [Hearth.com] All the heat goes up the chimney myth
 
snobuilder said:
That's just plain silly. They died from hard work and little healthcare .
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You need.to read better. I said "in part". Yes, your causes play a(partial) role too.
 
I went from trying to heat our place with an open fireplace (with the -Grate Wall of Fire-) to what I have now. Did the fireplace keep the house warm enough? Yes, in the immediate area of where the fireplace was and as long as I kept it stoked it radiated a fair amount of heat but also sent a buttload up the chimney. The rest of the house was cooler and got colder the further you moved away from it. I was also going through wood like mad. To compare an open fireplace to any high efficiency appliance is ridiculous. Even at 10% efficiency, if you throw enough wood at it you will see some net heat.
 
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JRHAWK9 said:
I went from trying to heat our place with an open fireplace (with the -Grate Wall of Fire-) to what I have now. Did the fireplace keep the house warm enough? Yes, in the immediate area of where the fireplace was and as long as I kept it stoked it radiated a fair amount of heat but also sent a buttload up the chimney. The rest of the house was cooler and got colder the further you moved away from it. I was also going through wood like mad. To compare an open fireplace to any high efficiency appliance is ridiculous. Even at 10% efficiency, if you throw enough wood at it you will see some net heat.
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10% is about the best that is possible from an open fireplace. Most are far less
 
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