I have referred several people to Mellow's thread since he did such a good job of documenting his work and temps. I don't recall off the top of my head exactly what temps I recorded before and after (thread is here somewhere) but was about 50 deg above ambient before insulating. Well worth the effort. I had less room for insulating the actual firebox but that's not where I was recording the largest heat loss anyway.
https://www.hearth.com/econtent/index.php/articles/making_a_block_off_plate/ is not redirecting properly by the way. I get that I need to lay it out on cardboard first but my question is more about cutting out/removing the steel that's up there now?
You don't want to do that with an insert especially not just with vermiculite. Just insulate with wrap. We pour in standalone chimneys often but almost never fireplaces with inserts
That was my plan, but 2 things have me concerned, one it looks like its nice and coated in flammable creosote right now, and 2, then I'll have a giant hole in my living room for water and down drafts...wait till winter is over?
I would not cut anything till you have the stove and liner there. The blockoff plate is not to stop water that should be done at the top of the chimney. As far as liners go we always use heavywall liners. there are allot of good manufacturers out there other than olympia for them. Really the only type i would not recommend it the 2ply lightwall liners they just dont hold up well at all
There should be no hole for rain or cold to come down. The flue cap, top cap and storm collar prevent this. The insulated block-off plate will control cold air seepage when the insert is not burning.
When you put a liner in it will come with a top plate that seals the top all but the liner opening and it will have its own cap. Yes occasionally a small amount of water may make it into the liner but it will end up in the stove and the block off plate will not be affected.
I was referring to the set up as is, where all I have is a cap on the flue, if/when I do cut the damper I was worried about rain going into through the grated cap I currently have. I'm probably going to leave it the hell alone until I can afford to get everything in my hands. knowing exact dimensions and profile of the insert will help me make a better insulated fireplace/blockoff plate, and finding out where the liner will come through the plate will be much easier once its in there. I will most likely have the existing flue cleaned professionally as I don't see the point of buying the brush to clean the flue and only clean it once (and they have 99 of my dollars). Or am I misunderstanding that the liner set up may still require cleaning of the terracotta flue?
the damper is not stopping any water either. And yes as i said before i would not cut anything till you have the stove and liner there
