Mirror as heat shield

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MagdalenaP

Burning Hunk
Nov 10, 2018
239
Tilbury, ON
Hey All!

Stove is a regency f2400 with glass door. Every so often I put the blower fan on to get more heat, or if I feel I'm a little to hot to overfiring, and I worry about the wood paneling getting too hot. I have a large mirror and was wondering if I could put it in front of the paneling?

An old pic from the realtor, the stove is right where the large clock is, facing the windows. You can just see behind the table, the wainscotting panel.

The clearance is to code (was installed professionally), but just still worried about the paneling. Anyone know what heat resistance mirror can stand up to?

Thanks in advance!

EDIT: ::DT;ex;ex;ex
I don't need a heat shield, I'm within clearance.

I *want* extra (and I have a mirror that fits nice there), and would like to know what temps can a mirror hold up to?
 

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I tried looking this up for your stove, but it doesn't define this clearance requirement. Some stoves say keep combustibles and furniture 36" away from the front. Yours just says keep them away, but generally speaking, I'd practice the 3' rule.

The key with shielding is having a proper air gap, say 1". If you just put the mirror up against the paneling, you're just creating a thermal bridge and achieve not a whole lot. Some people use corrugated sheet metal for their shield, so it's not necessarily the material, it just needs to be noncombustible. How much heat the mirror can take though, I'm not sure.
 
Hey All!

Stove is a regency f2400 with glass door. Every so often I put the blower fan on to get more heat, or if I feel I'm a little to hot to overfiring, and I worry about the wood paneling getting too hot. I have a large mirror and was wondering if I could put it in front of the paneling?

An old pic from the realtor, the stove is right where the large clock is, facing the windows. You can just see behind the table, the wainscotting panel.

The clearance is to code (was installed professionally), but just still worried about the paneling. Anyone know what heat resistance mirror can stand up to?

Thanks in advance!

Glass is not listed anywhere in the NFPA 211 as an approved clearance reduction material. I wouldn't want to use it myself. If you want to use something different I'd try corrugated metal with 1" spacers on the back side of it to keep it away from the wall.
 
I don't need a heat shield, I'm within clearance.

I *want* extra (and I have a mirror that fits nice there), and would like to know what temps can a mirror hold up to?
 
You should also get an updated picture instead of using the one from realtor. It seems you use this one in every one of your threads and it would be so much easier for everyone to understand the issue if they could see EXACTLY what you speak of.
 
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You should also get an updated picture instead of using the one from realtor. It seems you use this one in every one of your threads and it would be so much easier for everyone to understand the issue if they could see EXACTLY what you speak of.

Just wondering what temps a mirror can handle, that's all. That's the question. I'm well within clearance, it's just for my *extra* piece of mind :)
 
I don't need a heat shield, I'm within clearance.

I *want* extra (and I have a mirror that fits nice there), and would like to know what temps can a mirror hold up to?

It doesn't matter if that's what you want it for or not, that's what it will be. Here's an idea.....Google it!
 
Don't. Drop a split. Think of the luck factor;lol

No idea on the heat dissipation capability of mirror? Definitely the first time I've heard that considered. Attaching spacers to fix it to the wall could be challenging.
 
It doesn't matter if that's what you want it for or not, that's what it will be. Here's an idea.....Google it!

Let's consider the stove a sovereign country and the clearance requirements form it's territorial waters, and NFPA 211 are the laws of said country and its waters. Once outside the clearance requirements, you can do just about anything.

Let's use another case to demonstrate this.

Let's say my stove requires 3' of clearance to furniture and what not in front it. The side of my couch sits 4' away. I can put a wooden magazine holder, a combustible material, next to my leather couch if I prefer my leather to not take the beating of the radiation from the stove provided it's outside of that 3' range. I'm using it as a shield for my couch. Are you going to tell me that's not up to requirements?
 
Let's consider the stove a sovereign country and the clearance requirements form it's territorial waters, and NFPA 211 are the laws of said country and its waters. Once outside the clearance requirements, you can do just about anything.

Let's use another case to demonstrate this.

Let's say my stove requires 3' of clearance to furniture and what not in front it. The side of my couch sits 4' away. I can put a wooden magazine holder, a combustible material, next to my leather couch if I prefer my leather to not take the beating of the radiation from the stove provided it's outside of that 3' range. I'm using it as a shield for my couch. Are you going to tell me that's not up to requirements?

Yes, but - if that magazine holder was made of mirror, wouldn't you maybe like an idea of how much radiant heat it could stand?
 
Already tried, couldn't find an answer, I'll give you a gold star if you can though!

I found one reference of 470f for tempered glass. If that helps.
 
If you're trying to get these folks to consider something that doesn't play into their strict adherence to installation manuals and codes, you're barking up the wrong tree. LOL

I wouldn't see any harm in experimenting with it. Lean the mirror against the wall, fire the stove up, keep a good eye on it, and see how well it would work...

Worst case scenario would be that you ruin your mirror and have to opt for a more traditional shield material...

Sent from my SM-N950U using Tapatalk
 
I would indeed, that wasn't my point though.

Put a mirror too close though and it'll reflect too much radiation back to the stove and nuke it.

Hmm, seems to me from prior reading this has been a problematic install re. getting more stove heat into the room behind it.

Might be onto something here - it needs more mirrors!
 
If you're trying to get these folks to consider something that doesn't play into their strict adherence to installation manuals and codes, you're barking up the wrong tree. LOL

Well, it's likely not a good idea for advice to be publicly given that contradicts codes & installation manuals.....
 
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Hmm, seems to me from prior reading this has been a problematic install re. getting more stove heat into the room behind it.

Might be onto something here - it needs more mirrors!

Enough mirrors angled the right way, we might start creating lasers.

In all seriousness Magdalena, if it's outside of clearance requirements, you could be ok. If you have a way of measuring the mirror's temperature (ie IR gun), give it a shot and see what happens.
 
If you're trying to get these folks to consider something that doesn't play into their strict adherence to installation manuals and codes, you're barking up the wrong tree. LOL

This would be considered outside the jurisdiction of manuals and codes if clearances aren't in question. They don't govern what you do with the space beyond what they define.

It is, however, smart to ask the question about a mirror provided it can catch a lot of heat.
 
Let's consider the stove a sovereign country and the clearance requirements form it's territorial waters, and NFPA 211 are the laws of said country and its waters. Once outside the clearance requirements, you can do just about anything.

Let's use another case to demonstrate this.

Let's say my stove requires 3' of clearance to furniture and what not in front it. The side of my couch sits 4' away. I can put a wooden magazine holder, a combustible material, next to my leather couch if I prefer my leather to not take the beating of the radiation from the stove provided it's outside of that 3' range. I'm using it as a shield for my couch. Are you going to tell me that's not up to requirements?

For starters...In your example you are putting the magazine rack beyond the required clearance, not within it. Apples to oranges.

While there isn't a picture of this install to go off of, we can estimate that the stove would have the minimum clearance required which is 6" +/- I think. Otherwise you wouldn't be able to walk past the stove in that narrow room. My point is that when you stick something within the required clearances it, by default, becomes a heat shield. Intended or not. Maggie's question is regarding the thermal limits of said mirror to which I suggested Googling it. Seems like the logical place to look for the answer but I'd imagine there are ten thousand or so variables that would impact the answer and as someone else suggests, why risk breaking a nice mirror. Hence, the suggestion to use corrugated sheet metal to provide some measure of "extra protection" that she referred to at some point and also have a unique look.

Finally, she's in Canada and the NFPA doesn't apply to Canada. I use it for reference because that and the IRC are what we use here in the colonies.
 
If you're trying to get these folks to consider something that doesn't play into their strict adherence to installation manuals and codes, you're barking up the wrong tree. LOL

Well, it's likely not a good idea for advice to be publicly given that contradicts codes & installation manuals.....
Thanks for having the common sense to understand that. Obviously Shawn does not.
 
Maybe if you hot several mirrors and lined them up just right you could deflect the heat around that corner into your living room :p

Isn't a mirror basically glass? That far away I think it would be fine.
 
Is this post just about mirrors or is it about smoke and mirrors? Seriously, I think that it's an interesting topic as it applies to mirrors. In film projection back in the day dichroic mirrors were used in high heat situations. Heat not reflected, but light reflected lest the film would warp (focus problems). The only problem I see with putting a mirror near a wood stove is if the mirror is heated unevenly it may have a tendency to crack. What we used to do in television studios is, quite often we would "fly" a large front surface mirror above crew and actors behind the set. This was, needless to say potentially dangerous. So, what we would do is double stick tape a thin substrate behind it. MagdalenaP could do the same thing to assure, if it does break, shards won't be everywhere.
 
Depends on the temperature difference front to back.. roughly 60 to 80 c

Probably not a good idea


https://core.ac.uk/download/pdf/82491088.pdf

"Once a fire gets going, windows previously closed may crack and break
out. The fire developmental results will often be drastically different,
depending on whether the windows break or not. Thus, predicting the time
of glazing fall-out, when part of the wall becomes a new vent, is
essential to proper field modeling of compartment fires. The window pane
crack is caused by the increasing stress of the glass, which is induced
by the rising up temperature in the fire situation. Therefore, the
calculation of the temperature distribution is the first step and then
is the calculation of stress fields of the glass in fire. The
performance of glazing in fire has been tested on single and double pane
glazing1-4. Keski-Rahkonen 5 first predicted that a temperature
difference of about 80 °C based on his theoretical analysis of glass
cracking in fires. Pagni et al 6 predicted 58°C as the temperature
difference for crack initiation. Kelly et al7 conducted a series of
experiments in an unusual small-scale fire test room. Experiments in an
ISO compartment at the FireSERT Centre of the University of Ulster have
been performed and suggest that the glass remains in place until a crack
is initiated on each of the four window edges8 . Bifurcating cracks then
propagate and join, isolating a large portion of the pane from its
support. Although some experimental works were done and reliable results
were got, however, the tests are limited for theirs expensive and
materials consuming. Computer simulations were less reported comparing
with the experimental works9 . Herein, the finite element method is
employed to calculate the temperature distribution on the glass in fire,
and then the thermal stress distribution is calculated based on the
temperature distribution.
 
For starters...In your example you are putting the magazine rack beyond the required clearance, not within it. Apples to oranges.

Aren't we talking about putting a mirror in front of the stove, below the window where the table is in Magdalena's picture is to protect the wood paneling there? If we are, it's apples to apples if it's up to code.