insulating fireplace??

[trx680]

I'll be putting in a fireplace insert in my fireplace. I had one in there before but wasnt impressed with it soI sold it and will try another. When I had the other in there I noticed that the other side of the fireplace chimney, where the kitchen pantry is located, it was warm inside the pantry when using the woodstove. I want to avoid that since I store food in the pantry and I don't want temperature fluctuations.

Anyway, whats my best bet to keep the heat off of the brick so it wont transfer over to the pantry?
Yes, the insert will have a insulated liner. So the heat should only be coming from the insert itself.

 

[YoungGirlOldHouse]

I'm a newbie, but I was recently researching the same question (though I'm putting in a stove rather than an insert). I was searching for cosmetically acceptable radiant barriers and found Lizard Skin, which is a paint for cars to prevent them from getting hot. I called the company and although my use is unconventional, the man on the phone said he thought it would likely work. He said you can paint Lizard Skin directly on brick, and you need to use 4-5 coats to achieve the right thickness. If you're painting on metal, you need to use a primer of BBQ paint first (can get from Home Depot). My plan, which sounds like it would work for you, would be to paint black Lizard Skin paint on the three sides of the inside of your fireplace. The only thing is that I'm not sure how this would work with an insert: inserts have backplates that might keep the heat trapped in that space rather than allowing it to radiate back into the room. You could do the Lizard Skin paint option and then get a stove not an insert?

 

[kennyp2339]

Depending on how deep new insert is, you could get steel studs 2x4 and mount them along the back and sides of the fireplace, insulated with Roxul insulation and cut pieces of cement board to hold it all in place, while your in there, add the same insulation to the top (smoke shelf after the liner is in place, cover with either sheet metal or more cement board and you'll have a nice block off plate to keep even more of the inserts heat from going up the chimney and getting wasted.
There was a few threads here that members did what I'm referring to and have seen great results, this was on exterior chimneys and the problem was the chimney acting like a heat sink, the one guy took before and after temps reading with his laser thermometer and saw marked improvements.

 

[jetsam]

I used Roxul. If you want to get fancy, you can install Durock over top of it to give it a finished appearance.

 

[BeachBumm]

Depending on how deep new insert is, you could get steel studs 2x4 and mount them along the back and sides of the fireplace, insulated with Roxul insulation and cut pieces of cement board to hold it all in place, while your in there, add the same insulation to the top (smoke shelf after the liner is in place, cover with either sheet metal or more cement board and you'll have a nice block off plate to keep even more of the inserts heat from going up the chimney and getting wasted.

Kenny, Is is ok to place bats of Roxul directly along side and on top of the insert for insulation, as well as on the smoke shelf, around the SS liner and on top of the top cover?

 

[kennyp2339]

Roxul temp rate is 2,150 deg f, If you have temps anywhere near that you are having bigger issues. Average woodstove temp (in fire box) is 850 deg f, steel stoves start glowing at 900deg F at a 1,000deg you have an overfire situation. The temp of a chimney fire is around 2,000 deg f (liner that should be insulated with a ceramic blanket)
When working with roxul its always best to cover it with either cement board or sheet metal, roux; will settle overtime and you don't want to blow the dust around with the stoves blower.

 

[BeachBumm]

When working with roxul its always best to cover it with either cement board or sheet metal, roux; will settle overtime and you don't want to blow the dust around with the stoves blower.

Good point.