block off plate for sirocco 25 rockwool/comfortboard?

[Garfong]

So I got somewhat lackluster heat out of the stove this past winter (first winter). Wood was under 20% albeit just barely. Unfortunately, I wasn't there when they installed the stove. I had been told that the blockoff plate was part of the installation process. So we pulled the stove out a couple weeks ago to redo the surround, and so I figured this would be great opportunity to insulate behind the stove (thanks for inspiration Mellow).

Turns out they had just stuffed a little pink fiberglass insulation up around the flue area (maybe half a batt). So I yanked all of that out and shoved multiple batts of rockwool up there and zipped in comfort board around the interior. I even stuffed some more rockwool behind the comfortboard in the back.

Will a metal blockoff plate make a meaningful difference at this point? I should be able to put one in over the top piece of comfortboard, but I'm sitting here scratching my head as to if it is really worth the hassle. The back of the fireplace isn't uniform to seat it against. So I'm not sure if I can really get it sealed on the back edge.

 

[stoveliker]

Most folks add a plate with rockwool on top, screw the plate in place, and have a bead of silicone to seal.

Rockwool doesn't air seal well.

But I'm not sure that it's worth now, seeing the good things you did.

Regarding output: how did you test the moisturizer content?
It should be done on a split that is at room temperature, then split that thing in half, and measure with the pins parallel to the grain on the freshly exposed inside of the split.

 

[Garfong]

Good question, so I checked the moisture with multiple splits, but I didn't pay attention to the temperature at the time. The wood I have now is coming in around 15%.

I'll pull out some of the insulation and take another look at it.

 

[stoveliker]

Good question, so I checked the moisture with multiple splits, but I didn't pay attention to the temperature at the time. The wood I have now is coming in around 15%.

I'll pull out some of the insulation and take another look at it.

Okay. It that was on the inside of the splits, i.e. directly after you resplit one, then it's good.
If it was just measured on a split as you have it stacked then it will be much higher inside. Wood dried from the outside in.

If the shape of a would-be plate is awkward, get some cardboard to shape it out; easier to get it right than steel

 

[Garfong]

After removing the insulation and taking a closer look, it appears that the installers must have busted up alot of the masonry when they took out the damper because there's a mix of missing, broken, and loose brick. There's not really a solid spot to seal against on the back unless I do some masonry work. So I stuffed the last two batts I had left up there and buttoned her back up for now. I think I'll just see how it does this winter and open her back up and try again next spring if it's still struggling. Thanks for the help.

 

[BurningtoBlaze]

I am very curious to see how much a change you notice in output. I had a Ashford insert installed in March 2022 so this is only my third season with it but I’ve been admittedly disappointed in the output even with dry wood. I’ve thought about going down the insulation or block of plate route as well.