Questions About Insulating Around And Above An Insert

[Ralphie Boy]

This is my first full winter with my Buck 80 insert and I think it's telling me the installation could be better. I don't think I have the available funds to have a sheet metal mechanic fabricate something to seal the former damper area above my insert; so I was wondering if there is a safe and effective insulation that I could use to fill the area? Maybe a solid form that I could cut and fit into place. Should I insulate the walls of the old fireplace as well? And no the liner is not insulated because it's an 8" liner and the installers couldn't wrap the liner and get it through the chimney. Thanks for you ideas!

 

[begreen]

One doesn't need a sheet metal mechanic to make up a block-off plate. There are several examples of homemade ones here.
https://www.hearth.com/talk/wiki/why-damper-seal-is-needed/

Some folks report stuffing Roxul mineral wool around the flue above the damper area has been effective. You could try that at first and note the change.

 

[Makers Mark]

Roxul is the bomb! I put it above damper and stuffed it down top under top plate. This summer I'm going to pull insert and put it on top, sides, and back.

 

[Ralphie Boy]

Roxul is the bomb! I put it above damper and stuffed it down top under top plate. This summer I'm going to pull insert and put it on top, sides, and back.

How will/did you attach it?

 

[weatherguy]

One member just did what you want to do, he used roxul all around and then cut some micor and covered all the roxul, I Believe he painted it black and it all blended nicely. Shouldn't be too expensive to do it all. Metal for a block off plate is >$10 and you need tin snips, harbor freight has some cheap.

 

[stejus]

Go to this thread and you'll see how he put Roxul in the damper area.

https://www.hearth.com/talk/threads/a-square-peg-in-a-round-hole.71287/page-3

 

[Sons924]

I didn't insulate around my insert because it's an interior wall, but I did shove a ton of roxul into the damper opening. Made a huge difference in the heat output!

 

[etiger2007]

Call your installer or Buck and see if this will void your warranty, if they give you their blessing use roxul in your fireplace smoke shelf above your insert and do the sides and back of your insert, do not put insulation directly on top of your insert. I did this and it helped a great deal, good luck. With roxul it is ok to touch your insert.

 

[Woody Stover]

Last fall, I put Roxul right above the lintel, almost like a top on the fireplace, then left the surround off the 91 to allow the heat to escape into the room. I cut it a little larger than the opening, and it is fairly stiff (not like the pink stuff) so it holds itself up in there.