Insulation around insert

atom631

Member
May 3, 2014
96
Northeast, USA
I have a pacific energy summit. I’m doing some maintenance on it since it rattles so much. I pulled the surround off and noticed that there is a lot of vacant space around the insert and I’m not sure if I should insulate around it. Also, as you can see I have no block off plate and the installers stuffed some insulation up there but it doesn’t look like a lot. It looks like standard insulation to me, but I’m not really sure.

Also - you can see in the pics that there were some knockouts that i discovered when I pulled the surround off that were just hanging. I think this might be the source of the rattle as well as allowing a lot of the air from the blower escape into open cavity around the insert. I tack-welded some angle iron on the knockouts and re-sat them. It’s not pretty but i think it will do the job. Just hope it doesn’t rattle even more though.

With all that, should I add insulation around the liner and should I insulation around the insert? If so, can I use regular insulation or do I need roxaull?

See images below.
 

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weatherguy

Minister of Fire
Feb 20, 2009
5,359
Central Mass
Use roxul and you can still do a block off plate, I did my first one after my insert was installed.
 
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atom631

Member
May 3, 2014
96
Northeast, USA
Did you follow a guide? I’m assuming the two pieces meet at the flue pipe? How did you secure the plate behind the pipe? And on the inside wall (towards inside the house). I thought about doing this but wasn’t sure it could be done. Did you just use some thin sheet metal? Can it be caulked with some sort of heat-resistant silicone instead of screwed?

also - let’s say I can get it done, I would still want to insulate the cavity around the insert, esp since my fireplace/chimney is exterior...should I just wrap itIn roxall against the insert and then any leftover space just fill will regular insulation?
 
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Bushels20

Feeling the Heat
May 20, 2018
378
OH
Did you follow a guide? I’m assuming the two pieces meet at the flue pipe? How did you secure the plate behind the pipe? And on the inside wall (towards inside the house). I thought about doing this but wasn’t sure it could be done. Did you just use some thin sheet metal? Can it be caulked with some sort of heat-resistant silicone instead of screwed?

also - let’s say I can get it done, I would still want to insulate the cavity around the insert, esp since my fireplace/chimney is exterior...should I just wrap itIn roxall against the insert and then any leftover space just fill will regular insulation?

There are some good “how to” threads on here. Search block off plates. But ultimately, I folded over the edges of my metal and used Tap Cons to connect the sheet metal (24 gauge galvanized as I recall) to the brick. Some will say do not use galvanized but I got the stamp of approval from some professionals on here.

The two pieces meet at the liner/pipe. You then seal the two pieces with high temp sealant.

Insulate around the insert (not touching the insert) with Roxul. Not regular insulation. Also, stuff a bunch up around the liner prior to installing the block off plate. You basically want to insulate the top of the block off plate.

Use cardboard as a template to “dry fit” your design. Once comfortable, trace onto the sheet metal leaving a lip to bed over for attachment.

Once attached, seal very possible crack and joint with high temp sealant in an effort to make the install air tight.
 

atom631

Member
May 3, 2014
96
Northeast, USA
Thanks. I have a good buddy who is a union tin knocker. I showed him what I want to do and he said it’s a piece of cake. So I’ll probably try to get a block of plate installed. Then I’ll just place some roxall against the brick in the fireplace on all 3 sides around the insert. It will definitely touch the sides of the insert though.

I’m hoping between the block off plate, insulation and sealing up those knockouts that the installers left, it will be a lot more efficient. I’ve been going through 6 cords of wood a season on Long Island, NY. (Also had a new roof on my house installed and replaced a few old sliding doors and windows this summer). I think it will all help.
 

Bushels20

Feeling the Heat
May 20, 2018
378
OH
Thanks. I have a good buddy who is a union tin knocker. I showed him what I want to do and he said it’s a piece of cake. So I’ll probably try to get a block of plate installed. Then I’ll just place some roxall against the brick in the fireplace on all 3 sides around the insert. It will definitely touch the sides of the insert though.

I’m hoping between the block off plate, insulation and sealing up those knockouts that the installers left, it will be a lot more efficient. I’ve been going through 6 cords of wood a season on Long Island, NY. (Also had a new roof on my house installed and replaced a few old sliding doors and windows this summer). I think it will all help.

You will be happy after. It makes a big difference.
 
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atom631

Member
May 3, 2014
96
Northeast, USA
So the block off plate is going in towards the end of this week or beginning of next. The only issue is in that there isn’t much room from the top of the insert to where we can mount the plate. In fact, it might actually be flush with the top of the fireplace opening. That also poses a bit of an issue since the opening is framed with a steel plate On top that wraps around the inside. There really won’t be a way to secure it with tapcons. We were thinking either just use the high heat sealant and get at least 2 tapcons in on the other 3 sides or actually wrap the block off plate around the outside of the fireplace and get a tapcon in from the front above the edge of the steel plate. The surround for the insert would cover that all up and it wouldn’t be seen. See pics of the steel plate. What’s everyone’s thoughts on that?

Also - the other pic of the side shows how much room i have between the inside of the fireplace and the insert. If I put roxall in there it will definitely touch the sides and back of the insert. My thought was to leave the top open with no insulation since the block off plate will be there.
 

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Bushels20

Feeling the Heat
May 20, 2018
378
OH
So the block off plate is going in towards the end of this week or beginning of next. The only issue is in that there isn’t much room from the top of the insert to where we can mount the plate. In fact, it might actually be flush with the top of the fireplace opening. That also poses a bit of an issue since the opening is framed with a steel plate On top that wraps around the inside. There really won’t be a way to secure it with tapcons. We were thinking either just use the high heat sealant and get at least 2 tapcons in on the other 3 sides or actually wrap the block off plate around the outside of the fireplace and get a tapcon in from the front above the edge of the steel plate. The surround for the insert would cover that all up and it wouldn’t be seen. See pics of the steel plate. What’s everyone’s thoughts on that?

Also - the other pic of the side shows how much room i have between the inside of the fireplace and the insert. If I put roxall in there it will definitely touch the sides and back of the insert. My thought was to leave the top open with no insulation since the block off plate will be there.

Perhaps I am misunderstanding your explanation, however with a lip bent in to the block off plate (downward) this will give you the surface area to adhere the plate to the masonry with tap cons on all sides (except the front). You should be adding tap cons to the left, right and rear sides of the block off plate in to the masonry.

On the front, which has the “steel plate” you reference, which I think is the lintel plate (if I am interpreting your explanation correctly), you would seal this portion of the block off plate with the high temp sealant/adhere it to the lintel plate. I suppose you could tap through the lintel plate and then use some metal screws, but that lintel plate is some serious metal/would require some drilling. Mine is adhered and sealed at the seams and works just fine.

Once the install is complete, seal every possible nook and cranny with high temp sealant. Again, air tight is your goal. And don’t forget to insulate the top of the plate before install.
 

chazcarr

Minister of Fire
Jan 22, 2012
557
Southbury, CT
I have a pacific energy summit. I’m doing some maintenance on it since it rattles so much. I pulled the surround off and noticed that there is a lot of vacant space around the insert and I’m not sure if I should insulate around it. Also, as you can see I have no block off plate and the installers stuffed some insulation up there but it doesn’t look like a lot. It looks like standard insulation to me, but I’m not really sure.

Also - you can see in the pics that there were some knockouts that i discovered when I pulled the surround off that were just hanging. I think this might be the source of the rattle as well as allowing a lot of the air from the blower escape into open cavity around the insert. I tack-welded some angle iron on the knockouts and re-sat them. It’s not pretty but i think it will do the job. Just hope it doesn’t rattle even more though.

With all that, should I add insulation around the liner and should I insulation around the insert? If so, can I use regular insulation or do I need roxaull?

See images below.

Roxul works good used it twice. See pics at this thread

also for comparison see this other thread

I noticed a huge difference being insulated,
 

atom631

Member
May 3, 2014
96
Northeast, USA
Perhaps I am misunderstanding your explanation, however with a lip bent in to the block off plate (downward) this will give you the surface area to adhere the plate to the masonry with tap cons on all sides (except the front). You should be adding tap cons to the left, right and rear sides of the block off plate in to the masonry.

On the front, which has the “steel plate” you reference, which I think is the lintel plate (if I am interpreting your explanation correctly), you would seal this portion of the block off plate with the high temp sealant/adhere it to the lintel plate. I suppose you could tap through the lintel plate and then use some metal screws, but that lintel plate is some serious metal/would require some drilling. Mine is adhered and sealed at the seams and works just fine.

Once the install is complete, seal every possible nook and cranny with high temp sealant. Again, air tight is your goal. And don’t forget to insulate the top of the plate before install.
Not sure if you saw my mock-up pic of what Im talking about. I think that might make more sense. However, our first thought was to do exactly what you said, which would be a lot easier and cleaner. I just wasnt sure if not being able to screw the block off plate into the front would be an issue. If just using the high-temp sealant there works for you then that is probably the route we are going to go.

I already have some insulation around the pipe as you can see, so im going to keep that in there. do you think since it will be sealed off, i can use regular insulation to just pack it a little tighter before installing the plate? i have a ton of it around and it would save me $50-70 bux from not having to buy a whole pack of roxall.


Roxul works good used it twice. See pics at this thread

also for comparison see this other thread

I noticed a huge difference being insulated,
i just bought ceramic fiber blanket off ebay. Its only 1" think but I think it will do the job. The roxall is very thick and im not sure i even have the room to get it between the insert and the wall. i thought this stuff would give me that space. i figured if it doesnt stay in place, i can apply some high-heat sealant on the backside and just stick it to the wall.
 
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Bushels20

Feeling the Heat
May 20, 2018
378
OH
Not sure if you saw my mock-up pic of what Im talking about. I think that might make more sense. However, our first thought was to do exactly what you said, which would be a lot easier and cleaner. I just wasnt sure if not being able to screw the block off plate into the front would be an issue. If just using the high-temp sealant there works for you then that is probably the route we are going to go.

I already have some insulation around the pipe as you can see, so im going to keep that in there. do you think since it will be sealed off, i can use regular insulation to just pack it a little tighter before installing the plate? i have a ton of it around and it would save me $50-70 bux from not having to buy a whole pack of roxall.




i just bought ceramic fiber blanket off ebay. Its only 1" think but I think it will do the job. The roxall is very thick and im not sure i even have the room to get it between the insert and the wall. i thought this stuff would give me that space. i figured if it doesnt stay in place, i can apply some high-heat sealant on the backside and just stick it to the wall.
I would not use regular insulation. Perhaps you could, but it’s not worth the risk for $50.

I may be wrong, but I believe I read on here/was told that ceramic wool/fiber blanket is actually the “correct” way to insulate your insert. Meaning that is the way to keep it up to code. I’m not going to put words in to anyone’s mouth on here, but I recall a conversation I had with someone when we discussed that. I’m pretty sure I’m recalling it correctly. That said, us “non-pros” are just fine using Roxul I was told, but “pros” can not because it’s not the code/standard way to do it. 2 layers of 1” thick ceramic wool blanket I believe is what does the trick.

You must have gotten a good deal. As I recall that stuff is expensive.
 

atom631

Member
May 3, 2014
96
Northeast, USA
Alright. It’s not pretty and it’s far from perfect, but this is as good as it’s gonna get. We had an absolute hell of a time with this. The fireplace walls are not even. Nothing is level and the flu pipe is not straight up the chimney. It goes back on a 45 and the angles to the left about 30. And it’s not centered in the opening. We abandoned doing it with bent tabs and decided on l-brackets and a 2-piece block of plate.

First pic is what the brackets look like. And then we stuffed the hell out of the cavity with rockwool.

2nd pic is the block off plate and the start of some high-heat sealant. It was impossible to use the caulk gun. So we smeared it in with a knife as best we could. It’s not 100% sealed but it’s far better than what i had before.

3rd pic is with the block off plate in and then I added the ceramic fiber insulation to the walls around the insert. The back corners of the insert touch the walls so i couldn’t cover it 100%. 4th pic is just a shot of the ceramic insulation down the side. It’s 1” thick so it leaves a little breathing room to the sides of the insert.

I then added some high-heat sealant to all the tabs on the blower cover, surround and lid. My hope is that will help stop the pieces from backing out and vibrating when it gets hot.
 

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