Benefit of insulating firebox walls or wood insert ?

[KeepWarmInWinter]

Hi,
My apology if this question has been answered already on this forum. I am searching it but couldn't find this topic.
We are going to buy 2" Roxul Rockboard 60 board to insulate block off plates (top and damper area).
Is there any benefit to insulate the firebox walls or insert? If yes, what are recommended materials (rockboard, ceramic wool wrap, etc)? As always, thanks for all advice on this site.

 

[oconnor]

The main benefit would be when you have a fireplace on an outside wall. I wouldn't insulate against the insert. From a code perspective, you would want anything you use to be classed as a non-combustible - some of the Roxul products are, and others are just flame retardant.

 

[begreen]

I'd try a damper block off plate first, but in cold climates with unchased exterior, masonry fireplaces, there can be some improvement in performance.

This was discussed recently, here's a link:
https://www.hearth.com/econtent/index.php/forums/viewthread/59864/

 

[KeepWarmInWinter]

Thanks CleanBernin and GoGreen,
Our fireplace is on an outside wall, so insulating of firebox walls will help. I have reviewed discussions on this topic that was very helpful. We will buy Roxul mineral wool batts or boards from http://www.atsacoustics.com/cat--Fiberglass-and-Mineral-Wool-Batts-and-Boards--106.html site. We will cover it with heavy duty aluminum foil or steel sheet. We have not yet decided on which materials to use (batts/board, aluminum foil/steel sheet) and if insulate all walls versus only the back wall? What is your opinion?

 

[begreen]

I wouldn't worry about covering it with metal. Just attach the Roxul board with tapcons and large washers. This is a captive space, nothing is going to be banging up against the roxul once the insert is in place.

What insert is going to be installed?

 

[KeepWarmInWinter]

BeGreen, thank you for your advice. We want to do only what is necessary. We will be installing the Clydesdale.

 

[begreen]

Sounds good, the blowers are in the front and will stay cool.