damper/throat opening cover

[bwells794]

in order to allow a 6" liner to fit through the opening, the damper is being removed and in order to prevent massive heat loss up the chimney, can anyone recommend and products or materials that can essentially block or take up the space around the liner? Possibly some kind of insulation or non combustible board like material? Thanks!

Edit: for woodstove install

 

[bholler]

Search here for block off plates there are many threads on them. Most just use sheet metal but some use cement board or insulation board like micore. You can also use ceramic wool or roxul above the sheet metal for insulation

 

[Grisu]

I am not aware of any of the shelf solution but you can make your own block-off plate: https://www.hearth.com/talk/wiki/make-a-damper-sealing-block-off-plate/

If you stuff some Roxul in there before putting in the plate, the heat retention should be even better.

 

[begreen]

It's fairly easy to make one but if you want a kit, Ventinox makes one:
http://www.efireplacestore.com/cpf-18910.html
Here's another unknown brand that costs less.
https://servicesales.com/connector-sealing-kits-p-282.html