Necessity of Block off plate...

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Very interesting because there are many threads suggesting to put Roxul or other insulation around the bricks in your exterior masonary fireplace to keep the heat from absorbing into the bricks, I wonder if this applies to all manufactures inserts and if the warranty literature mentions it.

I'm curious too. I've never seen such a comment in any installation instructions.

I've used ceramic wool in the past behind inserts with no issues.
 
I am having a Voyage Grand put in next week . Reading all this very helpful information. I ask the install/salesperson. Insulation and this what he told me.

We do not put rock wool behind the block plate because it does not make much difference in stopping heat loss or air infiltration. As far as surrounding the insert it is not recommended and will void your warranty. It will cause the outside skin (convection chamber) to warp.

Any comments on this???
I don’t buy it!
It’s not always necessary, but can be very beneficial at times.
We did one yesterday that had frost on the bricks in the fireplace! My bricks were 27 degrees when I installed my insert. If there’s constant radiant cold there, I’ll stop it if I can. People go to great lengths to stop cold infiltration in there home and almost always overlook the fireplace.
 
I don’t pile it on the insert either. Instead it’s around the insert on the firebox walls, not touching the insert. There’s no way this would void any warranty.
 
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I don’t buy it!
It’s not always necessary, but can be very beneficial at times.
We did one yesterday that had frost on the bricks in the fireplace! Mine were 27 degrees when I installed my insert. If there’s constant radiant cold there, I’ll stop it if I can. People go to great lengths to stop cold infiltration in there home and almost always overlook the fireplace.

Do you think the manufacturer might be seeing this happen in warmer climates. The skin warping because the insert gets to hot.
 
Do you think the manufacturer might be seeing this happen in warmer climates. The skin warping because the insert gets to hot.
The climate wouldnt make a difference.
 
I don’t pile it on the insert either. Instead it’s around the insert on the firebox walls, not touching the insert. There’s no way this would void any warranty.
Agreed we insulate the box just not tight against the insert.
 
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I will not pack around the insert for that reason. But insulation ontop of the plate does make a difference

So you won't pack around the insert, but you will insulate the bricks, leaving adequate air space between the insert and the insulation?
 
The climate wouldnt make a difference.

If it's true that the manufacturer is concerned about skin warping, I think in a colder climate the heat would be pulled away from the insert more rapidly from ice cold bricks and in a warmer climate say 60 deg if you insulated the bricks the insert skin could over heat because you wouldn't have ice cold bricks pulling the heat away.

Interesting, I will need to call some manufacturers and talk to there engineers to see if this holds water.
 
So you won't pack around the insert, but you will insulate the bricks, leaving adequate air space between the insert and the insulation?
This is all anyone had suggested doing from what I’ve seen.
 
This is all anyone had suggested doing from what I’ve seen.

Maybe the salesman misunderstood what he ment by insulating the surround, maybe markie123 could clarify with his salesman that the insulation should not be touching the insert and see if he gets a different answer about warranty.
 
If it's true that the manufacturer is concerned about skin warping, I think in a colder climate the heat would be pulled away from the insert more rapidly from ice cold bricks and in a warmer climate say 60 deg if you insulated the bricks the insert skin could over heat because you wouldn't have ice cold bricks pulling the heat away.

Interesting, I will need to call some manufacturers and talk to there engineers to see if this holds water.
If this is the case, they need to beef up their build..
There’s no way a stove would be engineered so lightly that they would be depending on the brick to suck the heat away from it. I’m sure they don’t want insulation piled on their product though. With a little space between the stove and the insulation there won’t be any issues.

You may find really vague answers on this topic from manufacturers. They are really hard to get any solid answers on anything if they haven’t tested it that way.
 
If this is the case, they need to beef up their build..
There’s no way a stove would be engineered so lightly that they would be depending on the brick to suck the heat away from it. I’m sure they don’t want insulation piled on their product though. With a little space between the stove and the insulation there won’t be any issues.

You may find really vague answers on this topic from manufacturers. They are really hard to get any solid answers on anything if they haven’t tested it that way.

My only thinking would be that they test their inserts in brick fireplaces not insulated brick fireplaces.
 
If it's true that the manufacturer is concerned about skin warping, I think in a colder climate the heat would be pulled away from the insert more rapidly from ice cold bricks and in a warmer climate say 60 deg if you insulated the bricks the insert skin could over heat because you wouldn't have ice cold bricks pulling the heat away.

Interesting, I will need to call some manufacturers and talk to there engineers to see if this holds water.
Nope climate wont make a difference. If you notice none of the pros here pack against the insert because it is a concern
 
Nope climate wont make a difference. If you notice none of the pros here pack against the insert because it is a concern

Then that confirms that the salesman did not understand what he ment by insulating around the insert.
 
Then that confirms that the salesman did not understand what he ment by insulating around the insert.
What salesman and how does that confirm anything other than the 3 pros here on this thread agree it is a bad idea to pack insulation against the insert.
 
Many steel inserts have a very strong outer jacket, I don’t think it would ever be an issue on some of these units. It’s not necessary though.
 
What salesman and how does that confirm anything other than the 3 pros here on this thread agree it is a bad idea to pack insulation against the insert.

The whole conversation started out by markie123 telling us that his salesman said if you insulate around the insert it will cause it to warp and void the warranty, but we have no way of knowing if markie123 salesman understood how the insulation would be installed, tight up against the insert or an air gap left. So until markie123 can confirm the conversation with his salesman this whole conversation is mute!
 
The whole conversation started out by markie123 telling us that his salesman said if you insulate around the insert it will cause it to warp and void the warranty, but we have no way of knowing if markie123 salesman understood how the insulation would be installed, tight up against the insert or an air gap left. So until markie123 can confirm the conversation with his salesman this whole conversation is mute!
Ok i missed the salesperson part i thought he was talking to the installer my bad. But regardless their concern in a valid one. And it could very well void the warantee. They are looking out for him and dont want to do anything that could jeprodize the warranty.
 
Alternatively, if there’s metal all around where you plan to secure the plate, you can use welding magnets, I believe. I’ve not done it myself but that was supposed to be my summer project in my old home before I realized I’d be relocating. I think it was @weatherguy who gave me that idea, but I could be misremembering.
Might have been me, that's what I did and i s working great.
 
If it's true that the manufacturer is concerned about skin warping, I think in a colder climate the heat would be pulled away from the insert more rapidly from ice cold bricks and in a warmer climate say 60 deg if you insulated the bricks the insert skin could over heat because you wouldn't have ice cold bricks pulling the heat away.

Interesting, I will need to call some manufacturers and talk to there engineers to see if this holds water.
My only thinking would be that they test their inserts in brick fireplaces not insulated brick fireplaces.
The testing I've seen on Travis's factory floor is in an insulated metal cabinet with a ton of thermocouple sensors feeding into a computer.
 
Ok i missed the salesperson part i thought he was talking to the installer my bad. But regardless their concern in a valid one. And it could very well void the warantee. They are looking out for him and dont want to do anything that could jeprodize the warranty.
I've met stove salesmen that blow more smoke than the stove and I'll guess you have too. Some are far from a credible source.
 
I've met stove salesmen that blow more smoke than the stove and I'll guess you have too. Some are far from a credible source.
Agreed but in this case the concern is valid. And they do seem to be looking out for the customer. I think they are taking it to far. To me as long as you leave some room there is no danger but it really hasnt been tested.